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Distributed Denial-of-Service Open Threat Signaling (DOTS) Telemetry
draft-ietf-dots-telemetry-11

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 9244.
Authors Mohamed Boucadair , Tirumaleswar Reddy.K , Ehud Doron, Meiling Chen , Jon Shallow
Last updated 2020-07-27 (Latest revision 2020-07-10)
Replaces draft-reddy-dots-telemetry
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draft-ietf-dots-telemetry-11
DOTS                                                   M. Boucadair, Ed.
Internet-Draft                                                    Orange
Intended status: Standards Track                           T. Reddy, Ed.
Expires: January 28, 2021                                         McAfee
                                                                E. Doron
                                                            Radware Ltd.
                                                                 M. Chen
                                                                    CMCC
                                                              J. Shallow
                                                           July 27, 2020

  Distributed Denial-of-Service Open Threat Signaling (DOTS) Telemetry
                      draft-ietf-dots-telemetry-11

Abstract

   This document aims to enrich DOTS signal channel protocol with
   various telemetry attributes allowing optimal Distributed Denial-of-
   Service attack mitigation.  It specifies the normal traffic baseline
   and attack traffic telemetry attributes a DOTS client can convey to
   its DOTS server in the mitigation request, the mitigation status
   telemetry attributes a DOTS server can communicate to a DOTS client,
   and the mitigation efficacy telemetry attributes a DOTS client can
   communicate to a DOTS server.  The telemetry attributes can assist
   the mitigator to choose the DDoS mitigation techniques and perform
   optimal DDoS attack mitigation.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 28, 2021.

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Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   5
   3.  DOTS Telemetry: Overview and Purpose  . . . . . . . . . . . .   6
     3.1.  Need More Visibility  . . . . . . . . . . . . . . . . . .   6
     3.2.  Enhanced Detection  . . . . . . . . . . . . . . . . . . .   7
     3.3.  Efficient Mitigation  . . . . . . . . . . . . . . . . . .   9
   4.  Design Overview . . . . . . . . . . . . . . . . . . . . . . .   9
     4.1.  Overview of Telemetry Operations  . . . . . . . . . . . .   9
     4.2.  Generic Considerations  . . . . . . . . . . . . . . . . .  10
       4.2.1.  DOTS Client Identification  . . . . . . . . . . . . .  10
       4.2.2.  DOTS Gateways . . . . . . . . . . . . . . . . . . . .  10
       4.2.3.  Empty URI Paths . . . . . . . . . . . . . . . . . . .  10
       4.2.4.  Controlling Configuration Data  . . . . . . . . . . .  10
     4.3.  Block-wise Transfer . . . . . . . . . . . . . . . . . . .  11
     4.4.  DOTS Multi-homing Considerations  . . . . . . . . . . . .  11
     4.5.  YANG Considerations . . . . . . . . . . . . . . . . . . .  11
     4.6.  A Note About Examples . . . . . . . . . . . . . . . . . .  12
   5.  Telemetry Operation Paths . . . . . . . . . . . . . . . . . .  12
   6.  DOTS Telemetry Setup Configuration  . . . . . . . . . . . . .  13
     6.1.  Telemetry Configuration . . . . . . . . . . . . . . . . .  14
       6.1.1.  Retrieve Current DOTS Telemetry Configuration . . . .  14
       6.1.2.  Convey DOTS Telemetry Configuration . . . . . . . . .  16
       6.1.3.  Retrieve Installed DOTS Telemetry Configuration . . .  20
       6.1.4.  Delete DOTS Telemetry Configuration . . . . . . . . .  20
     6.2.  Total Pipe Capacity . . . . . . . . . . . . . . . . . . .  21
       6.2.1.  Convey DOTS Client Domain Pipe Capacity . . . . . . .  22
       6.2.2.  Retrieve Installed DOTS Client Domain Pipe Capacity .  27
       6.2.3.  Delete Installed DOTS Client Domain Pipe Capacity . .  27
     6.3.  Telemetry Baseline  . . . . . . . . . . . . . . . . . . .  28
       6.3.1.  Convey DOTS Client Domain Baseline Information  . . .  31
       6.3.2.  Retrieve Installed Normal Traffic Baseline  . . . . .  34

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       6.3.3.  Delete Installed Normal Traffic Baseline  . . . . . .  34
     6.4.  Reset Installed Telemetry Setup . . . . . . . . . . . . .  34
     6.5.  Conflict with Other DOTS Clients of the Same Domain . . .  34
   7.  DOTS Pre-or-Ongoing Mitigation Telemetry  . . . . . . . . . .  35
     7.1.  Pre-or-Ongoing-Mitigation DOTS Telemetry Attributes . . .  37
       7.1.1.  Target  . . . . . . . . . . . . . . . . . . . . . . .  38
       7.1.2.  Total Traffic . . . . . . . . . . . . . . . . . . . .  39
       7.1.3.  Total Attack Traffic  . . . . . . . . . . . . . . . .  40
       7.1.4.  Total Attack Connections  . . . . . . . . . . . . . .  42
       7.1.5.  Attack Details  . . . . . . . . . . . . . . . . . . .  45
     7.2.  From DOTS Clients to DOTS Servers . . . . . . . . . . . .  51
     7.3.  From DOTS Servers to DOTS Clients . . . . . . . . . . . .  54
   8.  DOTS Telemetry Mitigation Status Update . . . . . . . . . . .  59
     8.1.  DOTS Clients to Servers Mitigation Efficacy DOTS
           Telemetry Attributes  . . . . . . . . . . . . . . . . . .  59
     8.2.  DOTS Servers to Clients Mitigation Status DOTS Telemetry
           Attributes  . . . . . . . . . . . . . . . . . . . . . . .  61
   9.  Error Handling  . . . . . . . . . . . . . . . . . . . . . . .  65
   10. YANG Modules  . . . . . . . . . . . . . . . . . . . . . . . .  65
     10.1.  DOTS Signal Channel Telemetry YANG Module  . . . . . . .  65
     10.2.  Vendor Attack Mapping Details YANG Module  . . . . . . .  93
   11. YANG/JSON Mapping Parameters to CBOR  . . . . . . . . . . . .  96
   12. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  98
     12.1.  DOTS Signal Channel CBOR Key Values  . . . . . . . . . .  98
     12.2.  DOTS Signal Channel Conflict Cause Codes . . . . . . . . 101
     12.3.  DOTS Signal Telemetry YANG Module  . . . . . . . . . . . 101
   13. Security Considerations . . . . . . . . . . . . . . . . . . . 102
     13.1.  DOTS Signal Channel Telemetry  . . . . . . . . . . . . . 102
     13.2.  Vendor Attack Mapping  . . . . . . . . . . . . . . . . . 103
   14. Contributors  . . . . . . . . . . . . . . . . . . . . . . . . 104
   15. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . 104
   16. References  . . . . . . . . . . . . . . . . . . . . . . . . . 104
     16.1.  Normative References . . . . . . . . . . . . . . . . . . 104
     16.2.  Informative References . . . . . . . . . . . . . . . . . 106
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . 107

1.  Introduction

   Distributed Denial of Service (DDoS) attacks have become more
   sophisticated.  IT organizations and service providers are facing
   DDoS attacks that fall into two broad categories:

   1.  Network/Transport layer attacks target the victim's
       infrastructure.  These attacks are not necessarily aimed at
       taking down the actual delivered services, but rather to
       eliminate various network elements (routers, switches, firewalls,
       transit links, and so on) from serving legitimate users traffic.

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       The main method of such attacks is to send a large volume or high
       packet per second (pps) of traffic toward the victim's
       infrastructure.  Typically, attack volumes may vary from a few
       100 Mbps to 100s of Gbps or even Tbps.  Attacks are commonly
       carried out leveraging botnets and attack reflectors for
       amplification attacks such as NTP (Network Time Protocol), DNS
       (Domain Name System), SNMP (Simple Network Management Protocol),
       or SSDP (Simple Service Discovery Protocol).

   2.  Application layer attacks target various applications.  Typical
       examples include attacks against HTTP/HTTPS, DNS, SIP (Session
       Initiation Protocol), or SMTP (Simple Mail Transfer Protocol).
       However, all applications with their port numbers open at network
       edges can be attractive attack targets.

       Application layer attacks are considered more complex and hard to
       categorize, therefore harder to detect and mitigate efficiently.

   To compound the problem, attackers also leverage multi-vectored
   attacks.  These attacks are assembled from dynamic attack vectors
   (Network/Application) and tactics.  As such, multiple attack vectors
   formed by multiple attack types and volumes are launched
   simultaneously towards a victim.  Multi-vector attacks are harder to
   detect and defend.  Multiple and simultaneous mitigation techniques
   are needed to defeat such attack campaigns.  It is also common for
   attackers to change attack vectors right after a successful
   mitigation, burdening their opponents with changing their defense
   methods.

   The conclusion derived from these real scenarios is that modern
   attacks detection and mitigation are most certainly complicated and
   highly convoluted tasks.  They demand a comprehensive knowledge of
   the attack attributes, the targeted normal behavior (including,
   normal traffic patterns), as well as the attacker's on-going and past
   actions.  Even more challenging, retrieving all the analytics needed
   for detecting these attacks is not simple to obtain with the
   industry's current capabilities.

   The DOTS signal channel protocol [I-D.boucadair-dots-rfc8782-bis] is
   used to carry information about a network resource or a network (or a
   part thereof) that is under a DDoS attack.  Such information is sent
   by a DOTS client to one or multiple DOTS servers so that appropriate
   mitigation actions are undertaken on traffic deemed suspicious.
   Various use cases are discussed in [I-D.ietf-dots-use-cases].

   Typically, DOTS clients can be integrated within a DDoS attack
   detector, or network and security elements that have been actively
   engaged with ongoing attacks.  The DOTS client mitigation environment

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   determines that it is no longer possible or practical for it to
   handle these attacks.  This can be due to a lack of resources or
   security capabilities, as derived from the complexities and the
   intensity of these attacks.  In this circumstance, the DOTS client
   has invaluable knowledge about the actual attacks that need to be
   handled by its DOTS server(s).  By enabling the DOTS client to share
   this comprehensive knowledge of an ongoing attack under specific
   circumstances, the DOTS server can drastically increase its ability
   to accomplish successful mitigation.  While the attack is being
   handled by the DOTS server associated mitigation resources, the DOTS
   server has the knowledge about the ongoing attack mitigation.  The
   DOTS server can share this information with the DOTS client so that
   the client can better assess and evaluate the actual mitigation
   realized.

   DOTS clients can send mitigation hints derived from attack details to
   DOTS servers, with the full understanding that the DOTS server may
   ignore mitigation hints, as described in [RFC8612] (Gen-004).
   Mitigation hints will be transmitted across the DOTS signal channel,
   as the data channel may not be functional during an attack.  How a
   DOTS server is handling normal and attack traffic attributes, and
   mitigation hints is implementation specific.

   Both DOTS clients and servers can benefit this information by
   presenting various information in relevant management, reporting, and
   portal systems.

   This document defines DOTS telemetry attributes that can be conveyed
   by DOTS clients to DOTS servers, and vice versa.  The DOTS telemetry
   attributes are not mandatory attributes of the DOTS signal channel
   protocol [I-D.boucadair-dots-rfc8782-bis].  Nevertheless, when DOTS
   telemetry attributes are available to a DOTS agent, and absent any
   policy, it can signal the attributes in order to optimize the overall
   mitigation service provisioned using DOTS.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119][RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   The reader should be familiar with the terms defined in [RFC8612].

   "DOTS Telemetry" is defined as the collection of attributes that are
   used to characterize normal traffic baseline, attacks and their
   mitigation measures, and any related information that may help in

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   enforcing countermeasures.  The DOTS Telemetry is an optional set of
   attributes that can be signaled in the DOTS signal channel protocol.

   Telemetry Setup Identifier (tsid) is an identifier that is generated
   by DOTS clients to uniquely identify DOTS telemetry setup
   configuration data.

   Telemetry Identifier (tmid) is an identifier that is generated by
   DOTS clients to uniquely identify DOTS telemetry data that is
   communicated prior or during a mitigation.

   The meaning of the symbols in YANG tree diagrams are defined in
   [RFC8340] and [RFC8791].

3.  DOTS Telemetry: Overview and Purpose

   Timely and effective signaling of up-to-date DDoS telemetry to all
   elements involved in the mitigation process is essential and improves
   the overall DDoS mitigation service effectiveness.  Bi-directional
   feedback between DOTS agents is required for an increased awareness
   of each party, supporting superior and highly efficient attack
   mitigation service.

3.1.  Need More Visibility

   When signaling a mitigation request, it is most certainly beneficial
   for DOTS clients to signal to DOTS servers any knowledge regarding
   ongoing attacks.  This can happen in cases where DOTS clients are
   asking DOTS servers for support in defending against attacks that
   they have already detected and/or mitigated.

   If attacks are already detected and categorized within a DOTS client
   domain, the DOTS server, and its associated mitigation services, can
   proactively benefit this information and optimize the overall service
   delivery.  It is important to note that DOTS client domains and DOTS
   server domains detection and mitigation approaches can be different,
   and can potentially outcome different results and attack
   classifications.  The DDoS mitigation service treats the ongoing
   attack details received from DOTS clients as hints and cannot
   completely rely or trust the attack details conveyed by DOTS clients.

   A basic requirement of security operation teams is to be aware and
   get visibility into the attacks they need to handle.  The DOTS server
   security operation teams benefit from the DOTS telemetry, especially
   from the reports of ongoing attacks.  Even if some mitigation can be
   automated, operational teams can use the DOTS telemetry to be
   prepared for attack mitigation and to assign the correct resources
   (operation staff, networking and mitigation) for the specific

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   service.  Similarly, security operation personnel at the DOTS client
   side ask for feedback about their requests for protection.
   Therefore, it is valuable for DOTS servers to share DOTS telemetry
   with DOTS clients.

   Mutual sharing of information is thus crucial for "closing the
   mitigation loop" between DOTS clients and servers.  For the server
   side team, it is important to realize that the same attacks that the
   DOTS server's mitigation resources are seeing are those that a DOTS
   client is asking to mitigate.  For the DOTS client side team, it is
   important to realize that the DOTS clients receive the required
   service.  For example, understanding that "I asked for mitigation of
   two attacks and my DOTS server detects and mitigates only one of
   them".  Cases of inconsistency in attack classification between DOTS
   clients and servers can be highlighted, and maybe handled, using the
   DOTS telemetry attributes.

   In addition, management and orchestration systems, at both DOTS
   client and server sides, can use DOTS telemetry as a feedback to
   automate various control and management activities derived from
   signaled telemetry information.

   If the DOTS server's mitigation resources have the capabilities to
   facilitate the DOTS telemetry, the DOTS server adapts its protection
   strategy and activates the required countermeasures immediately
   (automation enabled) for the sake of optimized attack mitigation
   decisions and actions.

3.2.  Enhanced Detection

   DOTS telemetry can also be used to tune the DDoS mitigators with the
   correct state of an attack.  During the last few years, DDoS attack
   detection technologies have evolved from threshold-based detection
   (that is, cases when all or specific parts of traffic cross a
   predefined threshold for a certain period of time is considered as an
   attack) to an "anomaly detection" approach.  For the latter, it is
   required to maintain rigorous learning of "normal" behavior and where
   an "anomaly" (or an attack) is identified and categorized based on
   the knowledge about the normal behavior and a deviation from this
   normal behavior.  Machine learning approaches are used such that the
   actual traffic thresholds are automatically calculated by learning
   the protected entity normal traffic behavior during idle time.  The
   normal traffic characterization learned is referred to as the "normal
   traffic baseline".  An attack is detected when the victim's actual
   traffic is deviating from this normal baseline.

   In addition, subsequent activities toward mitigating an attack are
   much more challenging.  The ability to distinguish legitimate traffic

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   from attacker traffic on a per packet basis is complex.  For example,
   a packet may look "legitimate" and no attack signature can be
   identified.  The anomaly can be identified only after detailed
   statistical analysis.  DDoS attack mitigators use the normal baseline
   during the mitigation of an attack to identify and categorize the
   expected appearance of a specific traffic pattern.  Particularly, the
   mitigators use the normal baseline to recognize the "level of
   normality" needs to be achieved during the various mitigation
   process.

   Normal baseline calculation is performed based on continuous learning
   of the normal behavior of the protected entities.  The minimum
   learning period varies from hours to days and even weeks, depending
   on the protected application behavior.  The baseline cannot be
   learned during active attacks because attack conditions do not
   characterize the protected entities' normal behavior.

   If the DOTS client has calculated the normal baseline of its
   protected entities, signaling such information to the DOTS server
   along with the attack traffic levels is significantly valuable.  The
   DOTS server benefits from this telemetry by tuning its mitigation
   resources with the DOTS client's normal baseline.  The DOTS server
   mitigators use the baseline to familiarize themselves with the attack
   victim's normal behavior and target the baseline as the level of
   normality they need to achieve.  Fed with this inforamtion, the
   overall mitigation performances is expected to be improved in terms
   of time to mitigate, accuracy, false-negative, and false-positive.

   Mitigation of attacks without having certain knowledge of normal
   traffic can be inaccurate at best.  This is especially true for
   recursive signaling (see Section 3.2.3 in [I-D.ietf-dots-use-cases]).
   In addition, the highly diverse types of use cases where DOTS clients
   are integrated also emphasize the need for knowledge of each DOTS
   client domain behavior.  Consequently, common global thresholds for
   attack detection practically cannot be realized.  Each DOTS client
   domain can have its own levels of traffic and normal behavior.
   Without facilitating normal baseline signaling, it may be very
   difficult for DOTS servers in some cases to detect and mitigate the
   attacks accurately:

      It is important to emphasize that it is practically impossible for
      the DOTS server's mitigators to calculate the normal baseline in
      cases where they do not have any knowledge of the traffic
      beforehand.

      In addition, baseline learning requires a period of time that
      cannot be afforded during active attack.

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      Of course, this information can provided using out-of-band
      mechanisms or manual configuration at the risk to maintain
      inaccurate information as the network evolves and "normal"
      patterns change.  The use of a dynamic and collaborative means
      between the DOTS client and server to identify and share key
      parameters for the sake of efficient DDoS protection is valuable.

3.3.  Efficient Mitigation

   During a high volume attack, DOTS client pipes can be totally
   saturated.  DOTS clients ask their DOTS servers to handle the attack
   upstream so that DOTS client pipes return to a reasonable load level
   (normal pattern, ideally).  At this point, it is essential to ensure
   that the mitigator does not overwhelm the DOTS client pipes by
   sending back "clean traffic", or what it believes is "clean".  This
   can happen when the mitigator has not managed to detect and mitigate
   all the attacks launched towards the DOTS client domain.

   In this case, it can be valuable to DOTS clients to signal to DOTS
   servers the "total pipe capacity", which is the level of traffic the
   DOTS client domain can absorb from its upstream network.  Dynamic
   updates of the condition of pipes between DOTS agents while they are
   under a DDoS attack is essential (e.g., where multiple DOTS clients
   share the same physical connectivity pipes).  It is important to note
   that the term "pipe" noted here does not necessary represent physical
   pipe, but rather represents the maximum level of traffic that the
   DOTS client domain can receive.  The DOTS server should activate
   other mechanisms to ensure it does not allow the DOTS client domain's
   pipes to be saturated unintentionally.  The rate-limit action defined
   in [RFC8783] is a reasonable candidate to achieve this objective; the
   DOTS client can ask for the type(s) of traffic (such as ICMP, UDP,
   TCP port number 80) it prefers to limit.  The rate-limit action can
   be controlled via the signal channel
   [I-D.ietf-dots-signal-filter-control] even when the pipe is
   overwhelmed.

4.  Design Overview

4.1.  Overview of Telemetry Operations

   This document specifies an extension to the DOTS signal channel
   protocol.  Considerations about how to establish, maintain, and make
   use of the DOTS signal channel are specified in
   [I-D.boucadair-dots-rfc8782-bis].

   Once the DOTS signal channel is established, DOTS clients that
   support the DOTS telemetry extension proceed with the telemetry setup
   configuration (e.g., measurement interval, telemetry notification

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   interface, pipe capacity, normal traffic baseline) as detailed in
   Section 6.  DOTS agents can then include DOTS telemetry attributes
   using the DOTS signal channel (Section 7.1).  Typically, a DOTS
   client can use separate messages to share with its DOTS server(s) a
   set of telemetry data bound to an ongoing mitigation (Section 7.2).
   Also, a DOTS client that is interested to receive telemetry
   notifications related to some of its resources follows the procedure
   defined in Section 7.3.  The DOTS client can then decide to send a
   mitigation request if the notified attack cannot be mitigated locally
   within the DOTS client domain.

   Aggregate DOTS telemetry data can also be included in efficacy update
   (Section 8.1) or mitigation update (Section 8.2) messages.

4.2.  Generic Considerations

4.2.1.  DOTS Client Identification

   Following the rules in Section 5.4.1 of
   [I-D.boucadair-dots-rfc8782-bis], a unique identifier is generated by
   a DOTS client to prevent request collisions ('cuid').

   As a reminder, [I-D.boucadair-dots-rfc8782-bis] forbids 'cuid' to be
   returned in a response message body.

4.2.2.  DOTS Gateways

   DOTS gateways may be located between DOTS clients and servers.  The
   considerations elaborated in Section 5.4.1 of
   [I-D.boucadair-dots-rfc8782-bis] must be followed.  In particular,
   'cdid' attribute is used to unambiguously identify a DOTS client
   domain.

   As a reminder, [I-D.boucadair-dots-rfc8782-bis] forbids 'cdid' (if
   present) to be returned in a response message body.

4.2.3.  Empty URI Paths

   Uri-Path parameters and attributes with empty values MUST NOT be
   present in a request and render an entire message invalid.

4.2.4.  Controlling Configuration Data

   The DOTS server follows the same considerations discussed in
   Section of 5.5.3 of [I-D.boucadair-dots-rfc8782-bis] for managing
   DOTS telemetry configuration freshness and notification.

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   Likewise, a DOTS client may control the selection of configuration
   and non-configuration data nodes when sending a GET request by means
   of the 'c' Uri-Query option and following the procedure specified in
   Section of 5.4.2 of [I-D.boucadair-dots-rfc8782-bis].  These
   considerations are not reiterated in the following sections.

4.3.  Block-wise Transfer

   DOTS clients can use block wise transfer [RFC7959] with the
   recommendation detailed in Section 5.4.2 of
   [I-D.boucadair-dots-rfc8782-bis] to control the size of a response
   when the data to be returned does not fit within a single datagram.

   DOTS clients can also use CoAP Block1 Option in a PUT request (see
   Section 2.5 of [RFC7959]) to initiate large transfers, but these
   Block1 transfers will fail if the inbound "pipe" is running full, so
   consideration needs to be made to try to fit this PUT into a single
   transfer, or to separate out the PUT into several discrete PUTs where
   each of them fits into a single packet.

   Block3 and Block 4 Options that are similar to the CoAP Block1 and
   Block2 Options, but enable faster transmissions of big blocks of data
   with less packet interchanges, are defined in
   [I-D.bosh-core-new-block].  DOTS implementations can consider the use
   of Block3 and Block 4 Options.

4.4.  DOTS Multi-homing Considerations

   Multi-homed DOTS clients are assumed to follow the recommendations in
   [I-D.ietf-dots-multihoming] to select which DOTS server to contact
   and which IP prefixes to include in a telemetry message to a given
   peer DOTS server.  For example, if each upstream network exposes a
   DOTS server and the DOTS client maintains DOTS channels with all of
   them, only the information related to prefixes assigned by an
   upstream network to the DOTS client domain will be signaled via the
   DOTS channel established with the DOTS server of that upstream
   network.

   Considerations related to whether (and how) a DOTS client gleans some
   telemetry information (e.g., attack details) it receives from a first
   DOTS server and share it with a second DOTS server are implementation
   and deployment specific.

4.5.  YANG Considerations

   Telemetry messages exchanged between DOTS agents are serialized using
   Concise Binary Object Representation (CBOR) [RFC7049].  CBOR-encoded
   payloads are used to carry signal channel specific payload messages

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   which convey request parameters and response information such as
   errors.

   This document specifies a YANG module [RFC7950] for representing DOTS
   telemetry message types (Section 10.1).  All parameters in the
   payload of the DOTS signal channel are mapped to CBOR types as
   specified in Section 11.

   The DOTS telemetry module (Section 10.1) is not intended to be used
   via NETCONF/RESTCONF for DOTS server management purposes.  It serves
   only to provide a data model and encoding following [RFC8791].

   The DOTS telemetry module (Section 10.1) uses "enumerations" rather
   than "identities" to define units, samples, and intervals because
   otherwise the namespace identifier "ietf-dots-telemetry" must be
   included when a telemetry attribute is included (e.g., in a
   mitigation efficacy update).  The use of "identities" is thus
   suboptimal from a message compactness standpoint.

4.6.  A Note About Examples

   Examples are provided for illustration purposes.  The document does
   not aim to provide a comprehensive list of message examples.

   The authoritative reference for validating telemetry messages is the
   YANG module (Section 10.1) and the mapping table established in
   Section 11.

5.  Telemetry Operation Paths

   As discussed in Section 5.2 of [I-D.boucadair-dots-rfc8782-bis], each
   DOTS operation is indicated by a path suffix that indicates the
   intended operation.  The operation path is appended to the path
   prefix to form the URI used with a CoAP request to perform the
   desired DOTS operation.  The following telemetry path suffixes are
   defined (Table 1):

              +-----------------+----------------+-----------+
              | Operation       | Operation Path | Details   |
              +=================+================+===========+
              | Telemetry Setup | /tm-setup      | Section 6 |
              | Telemetry       | /tm            | Section 7 |
              +-----------------+----------------+-----------+

                     Table 1: DOTS Telemetry Operations

   Consequently, the "ietf-dots-telemetry" YANG module defined in
   Section 10.1 defines data structure to represent new DOTS message

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   types called 'telemetry-setup' and 'telemetry'.  The tree structure
   is shown in Figure 1.  More details are provided in Sections 6 and 7
   about the exact structure of 'telemetry-setup' and 'telemetry'
   message types.

     structure dots-telemetry:
       +-- (telemetry-message-type)?
          +--:(telemetry-setup)
          |  ...
          |  +-- telemetry* []
          |     ...
          |     +-- (setup-type)?
          |        +--:(telemetry-config)
          |        |  ...
          |        +--:(pipe)
          |        |  ...
          |        +--:(baseline)
          |           ...
          +--:(telemetry)
             ...

          Figure 1: New DOTS Message Types (YANG Tree Structure)

6.  DOTS Telemetry Setup Configuration

   In reference to Figure 1, a DOTS telemetry setup message MUST include
   only telemetry-related configuration parameters (Section 6.1) or
   information about DOTS client domain pipe capacity (Section 6.2) or
   telemetry traffic baseline (Section 6.3).  As such, requests that
   include a mix of telemetry configuration, pipe capacity, or traffic
   baseline MUST be rejected by DOTS servers with a 4.00 (Bad Request).

   A DOTS client can reset all installed DOTS telemetry setup
   configuration data following the considerations detailed in
   Section 6.4.

   A DOTS server may detect conflicts when processing requests related
   to DOTS client domain pipe capacity or telemetry traffic baseline
   with requests from other DOTS clients of the same DOTS client domain.
   More details are included in Section 6.5.

   Telemetry setup configuration is bound to a DOTS client domain.  DOTS
   servers MUST NOT expect DOTS clients to send regular requests to
   refresh the telemetry setup configuration.  Any available telemetry
   setup configuration has a validity timeout of the DOTS association
   with a DOTS client domain.  DOTS servers MUST NOT reset 'tsid'
   because a session failed with a DOTS client.  DOTS clients update

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   their telemetry setup configuration upon change of a parameter that
   may impact attack mitigation.

   DOTS telemetry setup configuration request and response messages are
   marked as Confirmable messages (Section 2.1 of [RFC7252]).

6.1.  Telemetry Configuration

   A DOTS client can negotiate with its server(s) a set of telemetry
   configuration parameters to be used for telemetry.  Such parameters
   include:

   o  Percentile-related measurement parameters

   o  Measurement units

   o  Acceptable percentile values

   o  Telemetry notification interval

   o  Acceptable Server-originated telemetry

   Section 11.3 of [RFC2330] includes more details about computing
   percentiles.

6.1.1.  Retrieve Current DOTS Telemetry Configuration

   A GET request is used to obtain acceptable and current telemetry
   configuration parameters on the DOTS server.  This request may
   include a 'cdid' Uri-Path when the request is relayed by a DOTS
   gateway.  An example of such request is depicted in Figure 2.

   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"

      Figure 2: GET to Retrieve Current and Acceptable DOTS Telemetry
                               Configuration

   Upon receipt of such request, and assuming no error is encountered by
   processing the request, the DOTS server replies with a 2.05 (Content)
   response that conveys the current and telemetry parameters acceptable
   by the DOTS server.  The tree structure of the response message body
   is provided in Figure 3.  Note that the response also includes any
   pipe (Section 6.2) and baseline information (Section 6.3) maintained
   by the DOTS server for this DOTS client.

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   DOTS servers that support the capability of sending telemetry
   information to DOTS clients prior or during a mitigation
   (Section 8.2) sets 'server-originated-telemetry' under 'max-config-
   values' to 'true' ('false' is used otherwise).  If 'server-
   originated-telemetry' is not present in a response, this is
   equivalent to receiving a request with 'server-originated-telemetry'
   set to 'false'.

     structure dots-telemetry:
       +-- (telemetry-message-type)?
          +--:(telemetry-setup)
          |  +-- (direction)?
          |  |  +--:(server-to-client-only)
          |  |     +-- max-config-values
          |  |     |  +-- measurement-interval?          interval
          |  |     |  +-- measurement-sample?            sample
          |  |     |  +-- low-percentile?                percentile
          |  |     |  +-- mid-percentile?                percentile
          |  |     |  +-- high-percentile?               percentile
          |  |     |  +-- server-originated-telemetry?   boolean
          |  |     |  +-- telemetry-notify-interval?     uint32
          |  |     +-- min-config-values
          |  |     |  +-- measurement-interval?        interval
          |  |     |  +-- measurement-sample?          sample
          |  |     |  +-- low-percentile?              percentile
          |  |     |  +-- mid-percentile?              percentile
          |  |     |  +-- high-percentile?             percentile
          |  |     |  +-- telemetry-notify-interval?   uint32
          |  |     +-- supported-units
          |  |     |  +-- unit-config* [unit]
          |  |     |     +-- unit           unit-type
          |  |     |     +-- unit-status    boolean
          |  |     +-- query-type*            query-type
          |  +-- telemetry* []
          |     +-- (direction)?
          |     |  +--:(server-to-client-only)
          |     |     +-- tsid?                  uint32
          |     +-- (setup-type)?
          |        +--:(telemetry-config)
          |        |  +-- current-config
          |        |     +-- measurement-interval?          interval
          |        |     +-- measurement-sample?            sample
          |        |     +-- low-percentile?                percentile
          |        |     +-- mid-percentile?                percentile
          |        |     +-- high-percentile?               percentile
          |        |     +-- unit-config* [unit]
          |        |     |  +-- unit           unit-type
          |        |     |  +-- unit-status    boolean

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          |        |     +-- server-originated-telemetry?   boolean
          |        |     +-- telemetry-notify-interval?     uint32
          |        +--:(pipe)
          |        |  ...
          |        +--:(baseline)
          |           ...
          +--:(telemetry)
             ...

             Figure 3: Telemetry Configuration Tree Structure

   When both 'min-config-values' and 'max-config-values' attributes are
   present, the values carried in 'max-config-values' attributes MUST be
   greater or equal to their counterpart in 'min-config-values'
   attributes.

6.1.2.  Convey DOTS Telemetry Configuration

   PUT request is used to convey the configuration parameters for the
   telemetry data (e.g., low, mid, or high percentile values).  For
   example, a DOTS client may contact its DOTS server to change the
   default percentile values used as baseline for telemetry data.
   Figure 3 lists the attributes that can be set by a DOTS client in
   such PUT request.  An example of a DOTS client that modifies all
   percentile reference values is shown in Figure 4.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=123"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "current-config": {
             "low-percentile": "5.00",
             "mid-percentile": "65.00",
             "high-percentile": "95.00"
           }
         }
       ]
     }
   }

         Figure 4: PUT to Convey the DOTS Telemetry Configuration

   'cuid' is a mandatory Uri-Path parameter for PUT requests.

   The following additional Uri-Path parameter is defined:

   tsid:  Telemetry Setup Identifier is an identifier for the DOTS
        telemetry setup configuration data represented as an integer.
        This identifier MUST be generated by DOTS clients.  'tsid'
        values MUST increase monotonically (when a new PUT is generated
        by a DOTS client to convey new configuration parameters for the
        telemetry).

        The procedure specified in Section 5.4.1 of
        [I-D.boucadair-dots-rfc8782-bis] MUST be followed for 'tsid'
        rollover.

        This is a mandatory attribute. 'tsid' MUST follow 'cuid'.

   'cuid' and 'tsid' MUST NOT appear in the PUT request message body.

   At least one configurable attribute MUST be present in the PUT
   request.

   The PUT request with a higher numeric 'tsid' value overrides the DOTS
   telemetry configuration data installed by a PUT request with a lower

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   numeric 'tsid' value.  To avoid maintaining a long list of 'tsid'
   requests for requests carrying telemetry configuration data from a
   DOTS client, the lower numeric 'tsid' MUST be automatically deleted
   and no longer be available at the DOTS server.

   The DOTS server indicates the result of processing the PUT request
   using the following Response Codes:

   o  If the request is missing a mandatory attribute, does not include
      'cuid' or 'tsid' Uri-Path parameters, or contains one or more
      invalid or unknown parameters, 4.00 (Bad Request) MUST be returned
      in the response.

   o  If the DOTS server does not find the 'tsid' parameter value
      conveyed in the PUT request in its configuration data and if the
      DOTS server has accepted the configuration parameters, then a 2.01
      (Created) Response Code MUST be returned in the response.

   o  If the DOTS server finds the 'tsid' parameter value conveyed in
      the PUT request in its configuration data and if the DOTS server
      has accepted the updated configuration parameters, 2.04 (Changed)
      MUST be returned in the response.

   o  If any of the enclosed configurable attribute values are not
      acceptable to the DOTS server (Section 6.1.1), 4.22 (Unprocessable
      Entity) MUST be returned in the response.

      The DOTS client may retry and send the PUT request with updated
      attribute values acceptable to the DOTS server.

   By default, low percentile (10th percentile), mid percentile (50th
   percentile), high percentile (90th percentile), and peak (100th
   percentile) values are used to represent telemetry data.
   Nevertheless, a DOTS client can disable some percentile types (low,
   mid, high).  In particular, setting 'low-percentile' to '0.00'
   indicates that the DOTS client is not interested in receiving low-
   percentiles.  Likewise, setting 'mid-percentile' (or 'high-
   percentile') to the same value as 'low-percentile' (or 'mid-
   percentile') indicates that the DOTS client is not interested in
   receiving mid-percentiles (or high-percentiles).  For example, a DOTS
   client can send the request depicted in Figure 5 to inform the server
   that it is interested in receiving only high-percentiles.  This
   assumes that the client will only use that percentile type when
   sharing telemetry data with the server.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=569"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "current-config": {
             "low-percentile": "0.00",
             "mid-percentile": "0.00",
             "high-percentile": "95.00"
           }
         }
       ]
     }
   }

             Figure 5: PUT to Disable Low- and Mid-Percentiles

   DOTS clients can also configure the unit type(s) to be used for
   traffic-related telemetry data.  Typically, the supported unit types
   are: packets per second, bits per second, and bytes per second.

   DOTS clients that are interested to receive pre or ongoing mitigation
   telemetry (pre-or-ongoing-mitigation) information from a DOTS server
   (Section 8.2) MUST set 'server-originated-telemetry' to 'true'.  If
   'server-originated-telemetry' is not present in a PUT request, this
   is equivalent to receiving a request with 'server-originated-
   telemetry' set to 'false'.  An example of a request to enable pre-or-
   ongoing-mitigation telemetry from DOTS servers is shown in Figure 6.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=569"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "current-config": {
             "server-originated-telemetry": true
           }
         }
       ]
     }
   }

   Figure 6: PUT to Enable Pre-or-ongoing-mitigation Telemetry from the
                                DOTS server

6.1.3.  Retrieve Installed DOTS Telemetry Configuration

   A DOTS client may issue a GET message with 'tsid' Uri-Path parameter
   to retrieve the current DOTS telemetry configuration.  An example of
   such request is depicted in Figure 7.

   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=123"

      Figure 7: GET to Retrieve Current DOTS Telemetry Configuration

   If the DOTS server does not find the 'tsid' Uri-Path value conveyed
   in the GET request in its configuration data for the requesting DOTS
   client, it MUST respond with a 4.04 (Not Found) error Response Code.

6.1.4.  Delete DOTS Telemetry Configuration

   A DELETE request is used to delete the installed DOTS telemetry
   configuration data (Figure 8). 'cuid' and 'tsid' are mandatory Uri-
   Path parameters for such DELETE requests.

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   Header: DELETE (Code=0.04)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=123"

                 Figure 8: Delete Telemetry Configuration

   The DOTS server resets the DOTS telemetry configuration back to the
   default values and acknowledges a DOTS client's request to remove the
   DOTS telemetry configuration using 2.02 (Deleted) Response Code.  A
   2.02 (Deleted) Response Code is returned even if the 'tsid' parameter
   value conveyed in the DELETE request does not exist in its
   configuration data before the request.

   Section 6.4 discusses the procedure to reset all DOTS telemetry setup
   configuration.

6.2.  Total Pipe Capacity

   A DOTS client can communicate to the DOTS server(s) its DOTS client
   domain pipe information.  The tree structure of the pipe information
   is shown in Figure 9.

     structure dots-telemetry:
       +-- (telemetry-message-type)?
          +--:(telemetry-setup)
          |  ...
          |  +-- telemetry* []
          |     +-- (direction)?
          |     |  +--:(server-to-client-only)
          |     |     +-- tsid?                  uint32
          |     +-- (setup-type)?
          |        +--:(telemetry-config)
          |        |  ...
          |        +--:(pipe)
          |        |  +-- total-pipe-capacity* [link-id unit]
          |        |     +-- link-id     nt:link-id
          |        |     +-- capacity    uint64
          |        |     +-- unit        unit
          |        +--:(baseline)
          |           ...
          +--:(telemetry)
             ...

                       Figure 9: Pipe Tree Structure

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   A DOTS client domain pipe is defined as a list of limits of
   (incoming) traffic volume ('total-pipe-capacity') that can be
   forwarded over ingress interconnection links of a DOTS client domain.
   Each of these links is identified with a 'link-id' [RFC8345].

   The unit used by a DOTS client when conveying pipe information is
   captured in 'unit' attribute.

6.2.1.  Convey DOTS Client Domain Pipe Capacity

   Similar considerations to those specified in Section 6.1.2 are
   followed with one exception:

      The relative order of two PUT requests carrying DOTS client domain
      pipe attributes from a DOTS client is determined by comparing
      their respective 'tsid' values.  If such two requests have
      overlapping 'link-id' and 'unit', the PUT request with higher
      numeric 'tsid' value will override the request with a lower
      numeric 'tsid' value.  The overlapped lower numeric 'tsid' MUST be
      automatically deleted and no longer be available.

   DOTS clients SHOULD minimize the number of active 'tsids' used for
   pipe information.  Typically, in order to avoid maintaining a long
   list of 'tsids' for pipe information, it is RECOMMENDED that DOTS
   clients include in any request to update information related to a
   given link the information of other links (already communicated using
   a lower 'tsid' value).  Doing so, this update request will override
   these existing requests and hence optimize the number of 'tsid'
   request per DOTS client.

   o  Note: This assumes that all link information can fit in one single
      message.

   For example, a DOTS client managing a single homed domain (Figure 10)
   can send a PUT request (shown in Figure 11) to communicate the
   capacity of "link1" used to connect to its ISP.

                         ,--,--,--.             ,--,--,--.
                      ,-'          `-.       ,-'          `-.
                     (  DOTS Client   )=====(     ISP#A      )
                      `-.  Domain  ,-' link1 `-.          ,-'
                         `--'--'--'             `--'--'--'

                Figure 10: Single Homed DOTS Client Domain

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=457"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "total-pipe-capacity": [
             {
               "link-id": "link1",
               "capacity": "500",
               "unit": "megabit-ps"
             }
           ]
         }
       ]
     }
   }

      Figure 11: Example of a PUT Request to Convey Pipe Information
                              (Single Homed)

   DOTS clients may be instructed to signal a link aggregate instead of
   individual links.  For example, a DOTS client that manages a DOTS
   client domain having two interconnection links with an upstream ISP
   (Figure 12) can send a PUT request (shown in Figure 13) to
   communicate the aggregate link capacity with its ISP.  Signalling
   individual or aggregate link capacity is deployment specific.

                         ,--,--,--.             ,--,--,--.
                      ,-'          `-.===== ,-'          `-.
                     (  DOTS Client   )    (     ISP#C      )
                      `-.  Domain  ,-'====== `-.          ,-'
                         `--'--'--'             `--'--'--'

       Figure 12: DOTS Client Domain with Two Interconnection Links

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=896"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "total-pipe-capacity": [
             {
               "link-id": "aggregate",
               "capacity": "700",
               "unit": "megabit-ps"
             }
           ]
         }
       ]
     }
   }

      Figure 13: Example of a PUT Request to Convey Pipe Information
                             (Aggregated Link)

   Now consider that the DOTS client domain was upgraded to connect to
   an additional ISP (e.g., ISP#B of Figure 14), the DOTS client can
   inform a third-party DOTS server (that is, not hosted with ISP#A and
   ISP#B domains) about this update by sending the PUT request depicted
   in Figure 15.  This request also includes information related to
   "link1" even if that link is not upgraded.  Upon receipt of this
   request, the DOTS server removes the request with 'tsid=457' and
   updates its configuration base to maintain two links (link#1 and
   link#2).

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                        ,--,--,--.
                      ,-'          `-.
                     (     ISP#B      )
                      `-.          ,-'
                         `--'--'--'
                             ||
                             || link2
                        ,--,--,--.             ,--,--,--.
                      ,-'          `-.       ,-'          `-.
                     (  DOTS Client   )=====(     ISP#A      )
                      `-.  Domain  ,-' link1 `-.          ,-'
                         `--'--'--'             `--'--'--'

                 Figure 14: Multi-Homed DOTS Client Domain

   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=458"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "total-pipe-capacity": [
             {
               "link-id": "link1",
               "capacity": "500",
               "unit": "megabit-ps"
             },
             {
               "link-id": "link2",
               "capacity": "500",
               "unit": "megabit-ps"
             }
           ]
         }
       ]
     }
   }

      Figure 15: Example of a PUT Request to Convey Pipe Information
                               (Multi-Homed)

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   A DOTS client can delete a link by sending a PUT request with the
   'capacity' attribute set to "0" if other links are still active for
   the same DOTS client domain (see Section 6.2.3 for other delete
   cases).  For example, if a DOTS client domain re-homes (that is, it
   changes its ISP), the DOTS client can inform its DOTS server about
   this update (e.g., from the network configuration in Figure 10 to the
   one shown in Figure 16) by sending the PUT request depicted in
   Figure 17.  Upon receipt of this request, and assuming no error is
   encountered when processing the request, the DOTS server removes
   "link1" from its configuration bases for this DOTS client domain.
   Note that if the DOTS server receives a PUT request with a 'capacity'
   attribute set to "0" for all included links, it MUST reject the
   request with a 4.00 (Bad Request).

                        ,--,--,--.
                      ,-'          `-.
                     (     ISP#B      )
                      `-.          ,-'
                         `--'--'--'
                             ||
                             || link2
                        ,--,--,--.
                      ,-'          `-.
                     (  DOTS Client   )
                      `-.  Domain  ,-'
                         `--'--'--'

                 Figure 16: Multi-Homed DOTS Client Domain

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=459"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "total-pipe-capacity": [
             {
               "link-id": "link1",
               "capacity": "0",
               "unit": "megabit-ps"
             },
             {
               "link-id": "link2",
               "capacity": "500",
               "unit": "megabit-ps"
             }
           ]
         }
       ]
     }
   }

      Figure 17: Example of a PUT Request to Convey Pipe Information
                               (Multi-Homed)

6.2.2.  Retrieve Installed DOTS Client Domain Pipe Capacity

   A GET request with 'tsid' Uri-Path parameter is used to retrieve a
   specific installed DOTS client domain pipe related information.  The
   same procedure as defined in Section 6.1.3 is followed.

   To retrieve all pipe information bound to a DOTS client, the DOTS
   client proceeds as specified in Section 6.1.1.

6.2.3.  Delete Installed DOTS Client Domain Pipe Capacity

   A DELETE request is used to delete the installed DOTS client domain
   pipe related information.  The same procedure as defined in
   Section 6.1.4 is followed.

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6.3.  Telemetry Baseline

   A DOTS client can communicate to its DOTS server(s) its normal
   traffic baseline and connections capacity:

   Total traffic normal baseline:  The percentile values representing
      the total traffic normal baseline.  It can be represented for a
      target using 'total-traffic-normal'.

      The traffic normal per protocol ('total-traffic-normal-per-
      protocol') baseline is represented for a target and is transport-
      protocol specific.

      The traffic normal per port number ('total-traffic-normal-per-
      port') baseline is represented for each port number bound to a
      target.

      If the DOTS client negotiated percentile values and units
      (Section 6.1), these negotiated values will be used instead of the
      default ones.

   Total connections capacity:  If the target is subjected to resource
      consuming DDoS attacks, the following optional attributes for the
      target per transport protocol are useful to detect resource
      consuming DDoS attacks:

      *  The maximum number of simultaneous connections that are allowed
         to the target.

      *  The maximum number of simultaneous connections that are allowed
         to the target per client.

      *  The maximum number of simultaneous embryonic connections that
         are allowed to the target.  The term "embryonic connection"
         refers to a connection whose connection handshake is not
         finished.  Embryonic connection is only possible in connection-
         oriented transport protocols like TCP or SCTP.

      *  The maximum number of simultaneous embryonic connections that
         are allowed to the target per client.

      *  The maximum number of connections allowed per second to the
         target.

      *  The maximum number of connections allowed per second to the
         target per client.

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      *  The maximum number of requests allowed per second to the
         target.

      *  The maximum number of requests allowed per second to the target
         per client.

      *  The maximum number of partial requests allowed per second to
         the target.  Attacks relying upon partial requests create a
         connection with a target but do not send a complete request
         (e.g., HTTP request).

      *  The maximum number of partial requests allowed per second to
         the target per client.

      The aggregate per transport protocol is captured in 'total-
      connection-capacity', while port specific capabilities are
      represented using 'total-connection-capacity-per-port'.

   The tree structure of the normal traffic baseline is shown in
   Figure 18.

     structure dots-telemetry:
       +-- (telemetry-message-type)?
          +--:(telemetry-setup)
          |  ...
          |  +-- telemetry* []
          |     +-- (direction)?
          |     |  +--:(server-to-client-only)
          |     |     +-- tsid?                  uint32
          |     +-- (setup-type)?
          |        +--:(telemetry-config)
          |        |  ...
          |        +--:(pipe)
          |        |  ...
          |        +--:(baseline)
          |           +-- baseline* [id]
          |              +-- id
          |              |       uint32
          |              +-- target-prefix*
          |              |       inet:ip-prefix
          |              +-- target-port-range* [lower-port]
          |              |  +-- lower-port    inet:port-number
          |              |  +-- upper-port?   inet:port-number
          |              +-- target-protocol*                      uint8
          |              +-- target-fqdn*
          |              |       inet:domain-name
          |              +-- target-uri*
          |              |       inet:uri

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          |              +-- alias-name*
          |              |       string
          |              +-- total-traffic-normal* [unit]
          |              |  +-- unit                 unit
          |              |  +-- low-percentile-g?    yang:gauge64
          |              |  +-- mid-percentile-g?    yang:gauge64
          |              |  +-- high-percentile-g?   yang:gauge64
          |              |  +-- peak-g?              yang:gauge64
          |              +-- total-traffic-normal-per-protocol*
          |              |       [unit protocol]
          |              |  +-- protocol             uint8
          |              |  +-- unit                 unit
          |              |  +-- low-percentile-g?    yang:gauge64
          |              |  +-- mid-percentile-g?    yang:gauge64
          |              |  +-- high-percentile-g?   yang:gauge64
          |              |  +-- peak-g?              yang:gauge64
          |              +-- total-traffic-normal-per-port* [unit port]
          |              |  +-- port                 inet:port-number
          |              |  +-- unit                 unit
          |              |  +-- low-percentile-g?    yang:gauge64
          |              |  +-- mid-percentile-g?    yang:gauge64
          |              |  +-- high-percentile-g?   yang:gauge64
          |              |  +-- peak-g?              yang:gauge64
          |              +-- total-connection-capacity* [protocol]
          |              |  +-- protocol                     uint8
          |              |  +-- connection?                  uint64
          |              |  +-- connection-client?           uint64
          |              |  +-- embryonic?                   uint64
          |              |  +-- embryonic-client?            uint64
          |              |  +-- connection-ps?               uint64
          |              |  +-- connection-client-ps?        uint64
          |              |  +-- request-ps?                  uint64
          |              |  +-- request-client-ps?           uint64
          |              |  +-- partial-request-ps?          uint64
          |              |  +-- partial-request-client-ps?   uint64
          |              +-- total-connection-capacity-per-port*
          |                      [protocol port]
          |                 +-- port
          |                 |       inet:port-number
          |                 +-- protocol                     uint8
          |                 +-- connection?                  uint64
          |                 +-- connection-client?           uint64
          |                 +-- embryonic?                   uint64
          |                 +-- embryonic-client?            uint64
          |                 +-- connection-ps?               uint64
          |                 +-- connection-client-ps?        uint64
          |                 +-- request-ps?                  uint64
          |                 +-- request-client-ps?           uint64

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          |                 +-- partial-request-ps?          uint64
          |                 +-- partial-request-client-ps?   uint64
          +--:(telemetry)
             ...

               Figure 18: Telemetry Baseline Tree Structure

6.3.1.  Convey DOTS Client Domain Baseline Information

   Similar considerations to those specified in Section 6.1.2 are
   followed with one exception:

      The relative order of two PUT requests carrying DOTS client domain
      baseline attributes from a DOTS client is determined by comparing
      their respective 'tsid' values.  If such two requests have
      overlapping targets, the PUT request with higher numeric 'tsid'
      value will override the request with a lower numeric 'tsid' value.
      The overlapped lower numeric 'tsid' MUST be automatically deleted
      and no longer be available.

   Two PUT requests from a DOTS client have overlapping targets if there
   is a common IP address, IP prefix, FQDN, URI, or alias-name.  Also,
   two PUT requests from a DOTS client have overlapping targets if the
   addresses associated with the FQDN, URI, or alias are overlapping
   with each other or with 'target-prefix'.

   DOTS clients SHOULD minimize the number of active 'tsids' used for
   baseline information.  Typically, in order to avoid maintaining a
   long list of 'tsids' for baseline information, it is RECOMMENDED that
   DOTS clients include in a request to update information related to a
   given target, the information of other targets (already communicated
   using a lower 'tsid' value) (assuming this fits within one single
   datagram).  This update request will override these existing requests
   and hence optimize the number of 'tsid' request per DOTS client.

   If no target clause is included in the request, this is an indication
   that the baseline information applies for the DOTS client domain as a
   whole.

   An example of a PUT request to convey the baseline information is
   shown in Figure 19.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=126"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "baseline": [
             {
               "id": 1,
               "target-prefix": [
                 "2001:db8:6401::1/128",
                 "2001:db8:6401::2/128"
               ],
               "total-traffic-normal": [
                 {
                   "unit": "megabit-ps",
                   "peak-g": "60"
                 }
               ]
             }
           ]
         }
       ]
     }
   }

            Figure 19: PUT to Convey the DOTS Traffic Baseline

   The DOTS client may share protocol specific baseline information
   (e.g., TCP and UDP) as shown in Figure 19.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tsid=128"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry-setup": {
       "telemetry": [
         {
           "baseline": [
             {
               "id": 1,
               "target-prefix": [
                 "2001:db8:6401::1/128",
                 "2001:db8:6401::2/128"
               ],
               "total-traffic-normal-per-protocol": [
                 {
                   "unit": "megabit-ps",
                   "protocol": 6,
                   "peak-g": "50"
                 },
                 {
                   "unit": "megabit-ps",
                   "protocol": 17,
                   "peak-g": "10"
                 }
               ]
             }
           ]
         }
       ]
     }
   }

          Figure 20: PUT to Convey the DOTS Traffic Baseline (2)

   The normal traffic baseline information should be updated to reflect
   legitimate overloads (e.g., flash crowds) to prevent unnecessary
   mitigation.

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6.3.2.  Retrieve Installed Normal Traffic Baseline

   A GET request with 'tsid' Uri-Path parameter is used to retrieve a
   specific installed DOTS client domain baseline traffic information.
   The same procedure as defined in Section 6.1.3 is followed.

   To retrieve all baseline information bound to a DOTS client, the DOTS
   client proceeds as specified in Section 6.1.1.

6.3.3.  Delete Installed Normal Traffic Baseline

   A DELETE request is used to delete the installed DOTS client domain
   normal traffic baseline.  The same procedure as defined in
   Section 6.1.4 is followed.

6.4.  Reset Installed Telemetry Setup

   Upon bootstrapping (or reboot or any other event that may alter the
   DOTS client setup), a DOTS client MAY send a DELETE request to set
   the telemetry parameters to default values.  Such a request does not
   include any 'tsid'.  An example of such request is depicted in
   Figure 21.

   Header: DELETE (Code=0.04)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm-setup"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"

                 Figure 21: Delete Telemetry Configuration

6.5.  Conflict with Other DOTS Clients of the Same Domain

   A DOTS server may detect conflicts between requests to convey pipe
   and baseline information received from DOTS clients of the same DOTS
   client domain. 'conflict-information' is used to report the conflict
   to the DOTS client following similar conflict handling discussed in
   Section 5.4.1 of [I-D.boucadair-dots-rfc8782-bis].  The conflict
   cause can be set to one of these values:

      1: Overlapping targets (Section 5.4.1 of
      [I-D.boucadair-dots-rfc8782-bis]).

      TBA: Overlapping pipe scope (see Section 12).

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7.  DOTS Pre-or-Ongoing Mitigation Telemetry

   There are two broad types of DDoS attacks, one is bandwidth consuming
   attack, the other is target resource consuming attack.  This section
   outlines the set of DOTS telemetry attributes (Section 7.1) that
   covers both the types of attacks.  The objective of these attributes
   is to allow for the complete knowledge of attacks and the various
   particulars that can best characterize attacks.

   The "ietf-dots-telemetry" YANG module (Section 10.1) defines the data
   structure of a new message type called 'telemetry'.  The tree
   structure of the 'telemetry' message type is shown in Figure 24.

   The pre-or-ongoing-mitigation telemetry attributes are indicated by
   the path suffix '/tm'.  The '/tm' is appended to the path prefix to
   form the URI used with a CoAP request to signal the DOTS telemetry.
   Pre-or-ongoing-mitigation telemetry attributes specified in
   Section 7.1 can be signaled between DOTS agents.

   Pre-or-ongoing-mitigation telemetry attributes may be sent by a DOTS
   client or a DOTS server.

   DOTS agents SHOULD bind pre-or-ongoing-mitigation telemetry data with
   mitigation requests relying upon the target clause.  In particular, a
   telemetry PUT request sent after a mitigation request may include a
   reference to that mitigation request ('mid-list') as shown in
   Figure 22.  An example illustrating requests correlation by means of
   'target-prefix' is shown in Figure 23.

   When generating telemetry data to send to a peer, the DOTS agent MUST
   auto-scale so that appropriate unit(s) are used.

   +-----------+                                           +-----------+
   |DOTS client|                                           |DOTS server|
   +-----------+                                           +-----------+
         |                                                       |
         |=========Mitigation Request (mid)=====================>|
         |                                                       |
         |================ Telemetry (mid-list{mid})============>|
         |                                                       |

           Figure 22: Example of Request Correlation using 'mid'

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   +-----------+                                           +-----------+
   |DOTS client|                                           |DOTS server|
   +-----------+                                           +-----------+
         |                                                       |
         |<=============== Telemetry (target-prefix)=============|
         |                                                       |
         |=========Mitigation Request (target-prefix)===========>|
         |                                                       |

       Figure 23: Example of Request Correlation using Target Prefix

   DOTS agents MUST NOT send pre-or-ongoing-mitigation telemetry
   notifications to the same peer more frequently than once every
   'telemetry-notify-interval' (Section 6.1).  If a telemetry
   notification is sent using a block-like transfer mechanism (e.g.,
   [I-D.bosh-core-new-block]), this rate limit policy MUST NOT consider
   these individual blocks as separate notifications, but as a single
   notification.

   DOTS pre-or-ongoing-mitigation telemetry request and response
   messages MUST be marked as Non-Confirmable messages (Section 2.1 of
   [RFC7252]).

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     structure dots-telemetry:
       +-- (telemetry-message-type)?
          +--:(telemetry-setup)
          |  ...
          |  +-- telemetry* []
          |     +-- (direction)?
          |     |  +--:(server-to-client-only)
          |     |     +-- tsid?                  uint32
          |     +-- (setup-type)?
          |        +--:(telemetry-config)
          |        |  ...
          |        +--:(pipe)
          |        |  ...
          |        +--:(baseline)
          |           ...
          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  ...
                +-- total-traffic* [unit]
                |  ...
                +-- total-traffic-protocol* [unit protocol]
                |  ...
                +-- total-traffic-port* [unit port]
                |  ...
                +-- total-attack-traffic* [unit]
                |  ...
                +-- total-attack-traffic-protocol* [unit protocol]
                |  ...
                +-- total-attack-traffic-port* [unit port]
                |  ...
                +-- total-attack-connection
                |  ...
                +-- total-attack-connection-port
                |  ...
                +-- attack-detail* [vendor-id attack-id]
                   ...

             Figure 24: Telemetry Message Type Tree Structure

7.1.  Pre-or-Ongoing-Mitigation DOTS Telemetry Attributes

   The description and motivation behind each attribute are presented in
   Section 3.  DOTS telemetry attributes are optionally signaled and

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   therefore MUST NOT be treated as mandatory fields in the DOTS signal
   channel protocol.

7.1.1.  Target

   A target resource (Figure 25) is identified using the attributes
   'target-prefix', 'target-port-range', 'target-protocol', 'target-
   fqdn', 'target-uri', 'alias-name', or a pointer to a mitigation
   request ('mid-list').

          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  +-- target-prefix*       inet:ip-prefix
                |  +-- target-port-range* [lower-port]
                |  |  +-- lower-port    inet:port-number
                |  |  +-- upper-port?   inet:port-number
                |  +-- target-protocol*     uint8
                |  +-- target-fqdn*         inet:domain-name
                |  +-- target-uri*          inet:uri
                |  +-- alias-name*          string
                |  +-- mid-list*            uint32
                +-- total-traffic* [unit]
                |  ...
                +-- total-traffic-protocol* [unit protocol]
                |  ...
                +-- total-traffic-port* [unit port]
                |  ...
                +-- total-attack-traffic* [unit]
                |  ...
                +-- total-attack-traffic-protocol* [unit protocol]
                |  ...
                +-- total-attack-traffic-port* [unit port]
                |  ...
                +-- total-attack-connection
                |  ...
                +-- total-attack-connection-port
                |  ...
                +-- attack-detail* [vendor-id attack-id]
                   ...

                     Figure 25: Target Tree Structure

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   At least one of the attributes 'target-prefix', 'target-fqdn',
   'target-uri', 'alias-name', or 'mid-list' MUST be present in the
   target definition.

   If the target is subjected to bandwidth consuming attack, the
   attributes representing the percentile values of the 'attack-id'
   attack traffic are included.

   If the target is subjected to resource consuming DDoS attacks, the
   same attributes defined for Section 7.1.4 are applicable for
   representing the attack.

   This is an optional subattribute.

7.1.2.  Total Traffic

   The 'total-traffic' attribute (Figure 26) conveys the percentile
   values of total traffic observed during a DDoS attack.  More granular
   total traffic can be conveyed in 'total-traffic-protocol' and 'total-
   traffic-port'.

   The 'total-traffic-protocol' represents the total traffic for a
   target and is transport-protocol specific.

   The 'total-traffic-port' represents the total traffic for a target
   per port number.

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          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  ...
                +-- total-traffic* [unit]
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-traffic-protocol* [unit protocol]
                |  +-- protocol             uint8
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-traffic-port* [unit port]
                |  +-- port                 inet:port-number
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-traffic* [unit]
                |  ...
                +-- total-attack-traffic-protocol* [unit protocol]
                |  ...
                +-- total-attack-traffic-port* [unit port]
                |  ...
                +-- total-attack-connection
                |  ...
                +-- total-attack-connection-port
                |  ...
                +-- attack-detail* [vendor-id attack-id]
                   ...

                  Figure 26: Total Traffic Tree Structure

7.1.3.  Total Attack Traffic

   The 'total-attack-traffic' attribute (Figure 27) conveys the total
   attack traffic identified by the DOTS client domain's DDoS Mitigation
   System (or DDoS Detector).  More granular total traffic can be

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   conveyed in 'total-attack-traffic-protocol' and 'total-attack-
   traffic-port'.

   The 'total-attack-traffic-protocol' represents the total attack
   traffic for a target and is transport-protocol specific.

   The 'total-attack-traffic-port' represents the total attack traffic
   for a target per port number.

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          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  ...
                +-- total-traffic* [unit]
                |  ...
                +-- total-traffic-protocol* [unit protocol]
                |  ...
                +-- total-traffic-port* [unit port]
                |  ...
                +-- total-attack-traffic* [unit]
                |  +-- protocol?            uint8
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-traffic-protocol* [unit protocol]
                |  +-- protocol             uint8
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-traffic-port* [unit port]
                |  +-- port                 inet:port-number
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-connection
                |  ...
                +-- total-attack-connection-port
                |  ...
                +-- attack-detail* [vendor-id attack-id]
                   ...

              Figure 27: Total Attack Traffic Tree Structure

7.1.4.  Total Attack Connections

   If the target is subjected to resource consuming DDoS attack, the
   'total-attack-connection' attribute is used to convey the percentile
   values of total attack connections.  The following optional

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   subattributes for the target per transport protocol are included to
   represent the attack characteristics:

   o  The number of simultaneous attack connections to the target.
   o  The number of simultaneous embryonic connections to the target.
   o  The number of attack connections per second to the target.
   o  The number of attack requests to the target.

   The total attack connections per port number is represented using
   'total-attack-connection-port' attribute.

          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  ...
                +-- total-traffic* [unit]
                |  ...
                +-- total-traffic-protocol* [unit protocol]
                |  ...
                +-- total-traffic-port* [unit port]
                |  ...
                +-- total-attack-traffic* [unit]
                |  ...
                +-- total-attack-traffic-protocol* [unit protocol]
                |  ...
                +-- total-attack-traffic-port* [unit port]
                |  ...
                +-- total-attack-connection
                |  +-- low-percentile-l* [protocol]
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64
                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- mid-percentile-l* [protocol]
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64
                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- high-percentile-l* [protocol]
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64

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                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- peak-l* [protocol]
                |     +-- protocol              uint8
                |     +-- connection?           yang:gauge64
                |     +-- embryonic?            yang:gauge64
                |     +-- connection-ps?        yang:gauge64
                |     +-- request-ps?           yang:gauge64
                |     +-- partial-request-ps?   yang:gauge64
                +-- total-attack-connection-port
                |  +-- low-percentile-l* [protocol port]
                |  |  +-- port                  inet:port-number
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64
                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- mid-percentile-l* [protocol port]
                |  |  +-- port                  inet:port-number
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64
                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- high-percentile-l* [protocol port]
                |  |  +-- port                  inet:port-number
                |  |  +-- protocol              uint8
                |  |  +-- connection?           yang:gauge64
                |  |  +-- embryonic?            yang:gauge64
                |  |  +-- connection-ps?        yang:gauge64
                |  |  +-- request-ps?           yang:gauge64
                |  |  +-- partial-request-ps?   yang:gauge64
                |  +-- peak-l* [protocol port]
                |     +-- port                  inet:port-number
                |     +-- protocol              uint8
                |     +-- connection?           yang:gauge64
                |     +-- embryonic?            yang:gauge64
                |     +-- connection-ps?        yang:gauge64
                |     +-- request-ps?           yang:gauge64
                |     +-- partial-request-ps?   yang:gauge64
                +-- attack-detail* [vendor-id attack-id]
                   ...

            Figure 28: Total Attack Connections Tree Structure

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7.1.5.  Attack Details

   This attribute (Figure 29) is used to signal a set of details
   characterizing an attack.  The following subattributes describing the
   ongoing attack can be signal as attack details.

   vendor-id:  Vendor ID is a security vendor's Enterprise Number as
      registered with IANA [Enterprise-Numbers].  It is a four-byte
      integer value.

   attack-id:  Unique identifier assigned for the attack.

   attack-description:  Textual representation of the attack
      description.  Natural Language Processing techniques (e.g., word
      embedding) can possibly be used to map the attack description to
      an attack type.  Textual representation of attack solves two
      problems: (a) avoids the need to create mapping tables manually
      between vendors and (b) avoids the need to standardize attack
      types which keep evolving.

   attack-severity:  Attack severity level.  This attribute takes one of
      the values defined in Section 3.12.2 of [RFC7970].

   start-time:  The time the attack started.  The attack's start time is
      expressed in seconds relative to 1970-01-01T00:00Z in UTC time
      (Section 2.4.1 of [RFC7049]).  The CBOR encoding is modified so
      that the leading tag 1 (epoch-based date/time) MUST be omitted.

   end-time:  The time the attack ended.  The attack end time is
      expressed in seconds relative to 1970-01-01T00:00Z in UTC time
      (Section 2.4.1 of [RFC7049]).  The CBOR encoding is modified so
      that the leading tag 1 (epoch-based date/time) MUST be omitted.

   source-count:  A count of sources involved in the attack targeting
      the victim.

   top-talkers:  A list of top talkers among attack sources.  The top
      talkers are represented using the 'source-prefix'.

      'spoofed-status' indicates whether a top talker is a spoofed IP
      address (e.g., reflection attacks) or not.

      If the target is subjected to a bandwidth consuming attack, the
      attack traffic from each of the top talkers is included ('total-
      attack-traffic', Section 7.1.3).

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      If the target is subjected to a resource consuming DDoS attack,
      the same attributes defined in Section 7.1.4 are applicable for
      representing the attack per talker.

          +--:(telemetry)
             +-- pre-or-ongoing-mitigation* []
                +-- (direction)?
                |  +--:(server-to-client-only)
                |     +-- tmid?                      uint32
                +-- target
                |  ...
                +-- total-traffic* [unit]
                |  ...
                +-- total-traffic-protocol* [unit protocol]
                |  ...
                +-- total-traffic-port* [unit port]
                |  ...
                +-- total-attack-traffic* [unit]
                |  ...
                +-- total-attack-traffic-protocol* [unit protocol]
                |  ...
                +-- total-attack-traffic-port* [unit port]
                |  ...
                +-- total-attack-connection
                |  ...
                +-- total-attack-connection-port
                |  ...
                +-- attack-detail* [vendor-id attack-id]
                   +-- vendor-id             uint32
                   +-- attack-id             uint32
                   +-- attack-description?   string
                   +-- attack-severity?      attack-severity
                   +-- start-time?           uint64
                   +-- end-time?             uint64
                   +-- source-count
                   |  +-- low-percentile-g?    yang:gauge64
                   |  +-- mid-percentile-g?    yang:gauge64
                   |  +-- high-percentile-g?   yang:gauge64
                   |  +-- peak-g?              yang:gauge64
                   +-- top-talker
                      +-- talker* [source-prefix]
                         +-- spoofed-status?            boolean
                         +-- source-prefix              inet:ip-prefix
                         +-- source-port-range* [lower-port]
                         |  +-- lower-port    inet:port-number
                         |  +-- upper-port?   inet:port-number
                         +-- source-icmp-type-range* [lower-type]
                         |  +-- lower-type    uint8

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                         |  +-- upper-type?   uint8
                         +-- total-attack-traffic* [unit]
                         |  +-- unit                 unit
                         |  +-- low-percentile-g?    yang:gauge64
                         |  +-- mid-percentile-g?    yang:gauge64
                         |  +-- high-percentile-g?   yang:gauge64
                         |  +-- peak-g?              yang:gauge64
                         +-- total-attack-connection
                            +-- low-percentile-l* [protocol]
                            |  +-- protocol              uint8
                            |  +-- connection?           yang:gauge64
                            |  +-- embryonic?            yang:gauge64
                            |  +-- connection-ps?        yang:gauge64
                            |  +-- request-ps?           yang:gauge64
                            |  +-- partial-request-ps?   yang:gauge64
                            +-- mid-percentile-l* [protocol]
                            |  +-- protocol              uint8
                            |  +-- connection?           yang:gauge64
                            |  +-- embryonic?            yang:gauge64
                            |  +-- connection-ps?        yang:gauge64
                            |  +-- request-ps?           yang:gauge64
                            |  +-- partial-request-ps?   yang:gauge64
                            +-- high-percentile-l* [protocol]
                            |  +-- protocol              uint8
                            |  +-- connection?           yang:gauge64
                            |  +-- embryonic?            yang:gauge64
                            |  +-- connection-ps?        yang:gauge64
                            |  +-- request-ps?           yang:gauge64
                            |  +-- partial-request-ps?   yang:gauge64
                            +-- peak-l* [protocol]
                               +-- protocol              uint8
                               +-- connection?           yang:gauge64
                               +-- embryonic?            yang:gauge64
                               +-- connection-ps?        yang:gauge64
                               +-- request-ps?           yang:gauge64
                               +-- partial-request-ps?   yang:gauge64

                  Figure 29: Attack Detail Tree Structure

   In order to optimize the size of telemetry data conveyed over the
   DOTS signal channel, DOTS agents MAY use the DOTS data channel
   [RFC8783] to exchange vendor specific attack mapping details (that
   is, {vendor identifier, attack identifier} ==> attack description).
   As such, DOTS agents do not have to convey systematically an attack
   description in their telemetry messages over the DOTS signal channel.

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   Multiple mappings for different vendor identifiers may be used; the
   DOTS agent transmitting telemetry information can elect to use one or
   more vendor mappings even in the same telemetry message.

      Note: It is possible that a DOTS server is making use of multiple
      DOTS mitigators; each from a different vendor.  How telemetry
      information and vendor mappings are exchanged between DOTS servers
      and DOTS mitigators is outside the scope of this document.

   DOTS clients and servers may be provided with mappings from different
   vendors and so have their own different sets of vendor attack
   mappings.  A DOTS agent MUST accept receipt of telemetry data with a
   vendor identifier that is different to the one it uses to transmit
   telemetry data.  Furthermore, it is possible that the DOTS client and
   DOTS server are provided by the same vendor, but the vendor mapping
   tables are at different revisions.  The DOTS client SHOULD transmit
   telemetry information using the vendor mapping(s) that it provided to
   the DOTS server and the DOTS server SHOULD use the vendor mappings(s)
   provided to the DOTS client when transmitting telemetry data to peer
   DOTS agent.

   The "ietf-dots-mapping" YANG module defined in Section 10.2 augments
   the "ietf-dots-data-channel" [RFC8783].  The tree structure of this
   module is shown in Figure 30.

   module: ietf-dots-mapping
     augment /ietf-data:dots-data/ietf-data:dots-client:
       +--rw vendor-mapping {dots-telemetry}?
          +--rw vendor* [vendor-id]
             +--rw vendor-id         uint32
             +--rw vendor-name?      string
             +--rw last-updated      uint64
             +--rw attack-mapping* [attack-id]
                +--rw attack-id             uint32
                +--rw attack-description    string
     augment /ietf-data:dots-data/ietf-data:capabilities:
       +--ro vendor-mapping-enabled?   boolean {dots-telemetry}?
     augment /ietf-data:dots-data:
       +--ro vendor-mapping {dots-telemetry}?
          +--ro vendor* [vendor-id]
             +--ro vendor-id         uint32
             +--ro vendor-name?      string
             +--ro last-updated      uint64
             +--ro attack-mapping* [attack-id]
                +--ro attack-id             uint32
                +--ro attack-description    string

              Figure 30: Vendor Attack Mapping Tree Structure

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   A DOTS client sends a GET request to retrieve the capabilities
   supported by a DOTS server as per Section 7.1 of [RFC8783].  This
   request is meant to assess whether vendor attack mapping details
   feature is supported by the server (i.e., check the value of 'vendor-
   mapping-enabled').

   If 'vendor-mapping-enabled' is set to 'true', A DOTS client MAY send
   a GET request to retrieve the DOTS server's vendor attack mapping
   details.  An example of such GET request is shown in Figure 31.

   GET /restconf/data/ietf-dots-data-channel:dots-data\
       /ietf-dots-mapping:vendor-mapping HTTP/1.1
   Host: example.com
   Accept: application/yang-data+json

      Figure 31: GET to Retrieve the Vendor Attack Mappings of a DOTS
                                  Server

   A DOTS client MAY retrieve only the list of vendors supported by the
   DOTS server.  It does so by setting the "depth" parameter
   (Section 4.8.2 of [RFC8040]) to "3" in the GET request as shown in
   Figure 32.  An example of a response body received from the DOTS
   server as a response to such request is illustrated in Figure 33.

   GET /restconf/data/ietf-dots-data-channel:dots-data\
       /ietf-dots-mapping:vendor-mapping?depth=3 HTTP/1.1
   Host: example.com
   Accept: application/yang-data+json

     Figure 32: GET to Retrieve the Vendors List used by a DOTS Server

   {
     "ietf-dots-mapping:vendor-mapping": {
       "vendor": [
         {
           "vendor-id": 1234,
           "vendor-name": "mitigator-s",
           "last-updated": "1576856561",
           "attack-mapping": []
         }
       ]
     }
   }

    Figure 33: Response to a GET to Retrieve the Vendors List used by a
                                DOTS Server

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   The DOTS client reiterates the above procedure regularly (e.g., once
   a week) to update the DOTS server's vendor attack mapping details.

   If the DOTS client concludes that the DOTS server does not have any
   reference to the specific vendor attack mapping details, the DOTS
   client uses a POST request to install its vendor attack mapping
   details.  An example of such POST request is depicted in Figure 34.

   POST /restconf/data/ietf-dots-data-channel:dots-data\
        /dots-client=dz6pHjaADkaFTbjr0JGBpw HTTP/1.1
   Host: example.com
   Content-Type: application/yang-data+json

   {
     "ietf-dots-mapping:vendor-mapping": {
       "vendor": [
         {
           "vendor-id": 345,
           "vendor-name": "mitigator-c",
           "last-updated": "1576812345",
           "attack-mapping": [
             {
               "attack-id": 1,
               "attack-description":
                  "Include a description of this attack"
             },
             {
               "attack-id": 2,
               "attack-description":
                  "Again, include a description of the attack"
             }
           ]
         }
       ]
     }
   }

         Figure 34: POST to Install Vendor Attack Mapping Details

   The DOTS server indicates the result of processing the POST request
   using the status-line.  Concretely, "201 Created" status-line MUST be
   returned in the response if the DOTS server has accepted the vendor
   attack mapping details.  If the request is missing a mandatory
   attribute or contains an invalid or unknown parameter, "400 Bad
   Request" status-line MUST be returned by the DOTS server in the
   response.  The error-tag is set to "missing-attribute", "invalid-
   value", or "unknown-element" as a function of the encountered error.

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   If the request is received via a server-domain DOTS gateway, but the
   DOTS server does not maintain a 'cdid' for this 'cuid' while a 'cdid'
   is expected to be supplied, the DOTS server MUST reply with "403
   Forbidden" status-line and the error-tag "access-denied".  Upon
   receipt of this message, the DOTS client MUST register (Section 5.1
   of [RFC8783]).

   The DOTS client uses the PUT request to modify its vendor attack
   mapping details maintained by the DOTS server (e.g., add a new
   mapping).

   A DOTS client uses a GET request to retrieve its vendor attack
   mapping details as maintained by the DOTS server (Figure 35).

   GET /restconf/data/ietf-dots-data-channel:dots-data\
       /dots-client=dz6pHjaADkaFTbjr0JGBpw\
       /ietf-dots-mapping:vendor-mapping?\
       content=all HTTP/1.1
   Host: example.com
   Accept: application/yang-data+json

    Figure 35: GET to Retrieve Installed Vendor Attack Mapping Details

   When conveying attack details in DOTS telemetry messages (Sections
   7.2, 7.3, and 8), DOTS agents MUST NOT include 'attack-description'
   attribute except if the corresponding attack mapping details were not
   shared with the peer DOTS agent.

7.2.  From DOTS Clients to DOTS Servers

   DOTS clients uses PUT request to signal pre-or-ongoing-mitigation
   telemetry to DOTS servers.  An example of such request is shown in
   Figure 36.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tmid=123"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry": {
       "pre-or-ongoing-mitigation": [
         {
           "target": {
             "target-prefix": [
               "2001:db8::1/128"
             ]
           },
           "total-attack-traffic-protocol": [
             {
               "protocol": 17,
               "unit": "megabit-ps",
               "mid-percentile-g": "900"
             }
           ],
           "attack-detail": [
             {
               "vendor-id": 1234,
               "attack-id": 77,
               "start-time": "1957811234",
               "attack-severity": "high"
             }
           ]
         }
       ]
     }
   }

        Figure 36: PUT to Send Pre-or-Ongoing-Mitigation Telemetry

   'cuid' is a mandatory Uri-Path parameter for PUT requests.

   The following additional Uri-Path parameter is defined:

   tmid:  Telemetry Identifier is an identifier for the DOTS pre-or-
        ongoing-mitigation telemetry data represented as an integer.
        This identifier MUST be generated by DOTS clients. 'tmid' values
        MUST increase monotonically (when a new PUT is generated by a
        DOTS client to convey pre-or-ongoing-mitigation telemetry).

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        The procedure specified in Section 5.4.1 of
        [I-D.boucadair-dots-rfc8782-bis] MUST be followed for 'tmid'
        rollover.

        This is a mandatory attribute. 'tmid' MUST follow 'cuid'.

   'cuid' and 'tmid' MUST NOT appear in the PUT request message body.

   At least 'target' attribute and another pre-or-ongoing-mitigation
   attributes (Section 7.1) MUST be present in the PUT request.  If only
   the 'target' attribute is present, this request is handled as per
   Section 7.3.

   The relative order of two PUT requests carrying DOTS pre-or-ongoing-
   mitigation telemetry from a DOTS client is determined by comparing
   their respective 'tmid' values.  If such two requests have
   overlapping 'target', the PUT request with higher numeric 'tmid'
   value will override the request with a lower numeric 'tmid' value.
   The overlapped lower numeric 'tmid' MUST be automatically deleted and
   no longer be available.

   The DOTS server indicates the result of processing a PUT request
   using CoAP Response Codes.  In particular, the 2.04 (Changed)
   Response Code is returned if the DOTS server has accepted the pre-or-
   ongoing-mitigation telemetry.  The 5.03 (Service Unavailable)
   Response Code is returned if the DOTS server has erred. 5.03 uses
   Max-Age Option to indicate the number of seconds after which to
   retry.

   How long a DOTS server maintains a 'tmid' as active or logs the
   enclosed telemetry information is implementation specific.  Note that
   if a 'tmid' is still active, then logging details are updated by the
   DOTS server as a function of the updates received from the peer DOTS
   client.

   A DOTS client that lost the state of its active 'tmids' or has to set
   'tmid' back to zero (e.g., crash or restart) MUST send a GET request
   to the DOTS server to retrieve the list of active 'tmid'.  The DOTS
   client may then delete 'tmids' that should not be active anymore
   (Figure 37).  Sending a DELETE with no 'tmid' indicates that all
   'tmids' must be deactivated (Figure 38).

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   Header: DELETE (Code=0.04)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tmid=123"

          Figure 37: Delete a Pre-or-Ongoing-Mitigation Telemetry

   Header: DELETE (Code=0.04)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"

         Figure 38: Delete All Pre-or-Ongoing-Mitigation Telemetry

7.3.  From DOTS Servers to DOTS Clients

   The pre-or-ongoing-mitigation (attack details, in particular) can
   also be signaled from DOTS servers to DOTS clients.  For example, the
   DOTS server co-located with a DDoS detector collects monitoring
   information from the target network, identifies DDoS attack using
   statistical analysis or deep learning techniques, and signals the
   attack details to the DOTS client.

   The DOTS client can use the attack details to decide whether to
   trigger a DOTS mitigation request or not.  Furthermore, the security
   operation personnel at the DOTS client domain can use the attack
   details to determine the protection strategy and select the
   appropriate DOTS server for mitigating the attack.

   In order to receive pre-or-ongoing-mitigation telemetry notifications
   from a DOTS server, a DOTS client MUST send a PUT (followed by a GET)
   with the target filter.  An example of such PUT request is shown in
   Figure 39.  In order to avoid maintaining a long list of such
   requests, it is RECOMMENDED that DOTS clients include all targets in
   the same request.  DOTS servers may be instructed to restrict the
   number of pre-or-ongoing-mitigation requests per DOTS client domain.
   This request MUST be maintained active by the DOTS server until a
   delete request is received from the same DOTS client to clear this
   pre-or-ongoing-mitigation telemetry.

   The relative order of two PUT requests carrying DOTS pre-or-ongoing-
   mitigation telemetry from a DOTS client is determined by comparing
   their respective 'tmid' values.  If such two requests have
   overlapping 'target', the PUT request with higher numeric 'tmid'
   value will override the request with a lower numeric 'tmid' value.

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   The overlapped lower numeric 'tmid' MUST be automatically deleted and
   no longer be available.

   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tmid=567"
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-telemetry:telemetry": {
       "pre-or-ongoing-mitigation": [
         {
           "target": {
             "target-prefix": [
               "2001:db8::/32"
             ]
           }
         }
       ]
     }
   }

       Figure 39: PUT to Request Pre-or-Ongoing-Mitigation Telemetry

   DOTS clients of the same domain can request to receive pre-or-
   ongoing-mitigation telemetry bound to the same target.

   The DOTS client conveys the Observe Option set to '0' in the GET
   request to receive asynchronous notifications carrying pre-or-
   ongoing-mitigation telemetry data from the DOTS server.  The GET
   request specifies a 'tmid' (Figure 40) or not (Figure 41).

   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "tmid=567"
   Observe: 0

    Figure 40: GET to Subscribe to Telemetry Asynchronous Notifications
                           for a Specific 'tmid'

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   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Observe: 0

    Figure 41: GET to Subscribe to Telemetry Asynchronous Notifications
                              for All 'tmids'

   The DOTS client can filter out the asynchronous notifications from
   the DOTS server by indicating one or more Uri-Query options in its
   GET request.  A Uri-Query option can include the following
   parameters: 'target-prefix', 'target-port', 'target-protocol',
   'target-fqdn', 'target-uri', 'alias-name', 'mid', and 'c' (content)
   (Section 4.2.4).  Furthermore:

      If more than one Uri-Query option is included in a request, these
      options are interpreted in the same way as when multiple target
      clauses are included in a message body.

      If multiple values of a query parameter are to be included in a
      request, these values MUST be included in the same Uri-Query
      option and separated by a "," character without any spaces.

      Range values (i.e., contiguous inclusive block) can be included
      for 'target-port', 'target-protocol', and 'mid' parameters by
      indicating two bound values separated by a "-" character.

      Wildcard names (i.e., a name with the leftmost label is the "*"
      character) can be included in 'target-fqdn' or 'target-uri'
      parameters.  DOTS clients MUST NOT include a name in which the "*"
      character is included in a label other than the leftmost label.
      "*.example.com" is an example of a valid wildcard name that can be
      included as a value of the 'target-fqdn' parameter in an Uri-Query
      option.

   DOTS clients may also filter out the asynchronous notifications from
   the DOTS server by indicating a specific source information.  To that
   aim, a DOTS client may include 'source-prefix', 'source-port', or
   'source-icmp-type' in a Uri-Query option.  The same considerations
   (ranges, multiple values) specified for target clauses apply for
   source clauses.  Special care SHOULD be taken when using these
   filters as some attacks may be hidden to the requesting DOTS client
   (e.g., the attack changes its source information).

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   Requests with invalid query types (e.g., not supported, malformed) by
   the DOTS server MUST be rejected by DOTS servers with a 4.00 (Bad
   Request).

   An example of request to subscribe to asynchronous UDP telemetry
   notifications is shown in Figure 42.  This filter will be applied for
   all 'tmids'.

   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "tm"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Query: "target-protocol=17"
   Observe: 0

         Figure 42: GET Request to Receive Telemetry Asynchronous
                  Notifications Filtered using Uri-Query

   The DOTS server will send asynchronous notifications to the DOTS
   client when an attack event is detected following similar
   considerations as in Section 5.4.2.1 of
   [I-D.boucadair-dots-rfc8782-bis].  An example of a pre-or-ongoing-
   mitigation telemetry notification is shown in Figure 43.

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   {
     "ietf-dots-telemetry:telemetry": {
       "pre-or-ongoing-mitigation": [
         {
           "tmid": 567,
           "target": {
             "target-prefix": [
               "2001:db8::1/128"
             ]
           },
           "target-protocol": [
             17
           ],
           "total-attack-traffic": [
             {
               "unit": "megabit-ps",
               "mid-percentile-g": "900"
             }
           ],
           "attack-detail": [
             {
               "vendor-id": 1234,
               "attack-id": 77,
               "start-time": "1957818434",
               "attack-severity": "high"
             }
           ]
         }
       ]
     }
   }

     Figure 43: Message Body of a Pre-or-Ongoing-Mitigation Telemetry
                     Notification from the DOTS Server

   A DOTS server sends the aggregate data for a target using 'total-
   attack-traffic' attribute.  The aggregate assumes that Uri-Query
   filters are applied on the target.  The DOTS server MAY include more
   granular data when needed (that is, 'total-attack-traffic-protocol'
   and 'total-attack-traffic-port').  If a port filter (or protocol
   filter) is included in a request, 'total-attack-traffic-protocol' (or
   'total-attack-traffic-port') conveys the data with the port (or
   protocol) filter applied.

   A DOTS server may aggregate pre-or-ongoing-mitigation data (e.g.,
   'top-talkers') for all targets of a domain, or when justified, send
   specific information (e.g., 'top-talkers') per individual targets.

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   The DOTS client may log pre-or-ongoing-mitigation telemetry data with
   an alert sent to an administrator or a network controller.  The DOTS
   client may send a mitigation request if the attack cannot be handled
   locally.

   A DOTS client that is not interested to receive pre-or-ongoing-
   mitigation telemetry data for a target MUST send a delete request
   similar to the one depicted in Figure 37.

8.  DOTS Telemetry Mitigation Status Update

8.1.  DOTS Clients to Servers Mitigation Efficacy DOTS Telemetry
      Attributes

   The mitigation efficacy telemetry attributes can be signaled from
   DOTS clients to DOTS servers as part of the periodic mitigation
   efficacy updates to the server (Section 6.3.4 of
   [I-D.boucadair-dots-rfc8782-bis]).

   Total Attack Traffic:   The overall attack traffic as observed from
      the DOTS client perspective during an active mitigation.  See
      Figure 27.

   Attack Details:   The overall attack details as observed from the
      DOTS client perspective during an active mitigation.  See
      Section 7.1.5.

   The "ietf-dots-telemetry" YANG module (Section 10.1) augments the
   'mitigation-scope' message type defined in "ietf-dots-signal"
   [I-D.boucadair-dots-rfc8782-bis] so that these attributes can be
   signalled by a DOTS client in a mitigation efficacy update
   (Figure 44).

     augment-structure /signal:dots-signal/signal:message-type
                       /signal:mitigation-scope/signal:scope:
       +-- total-attack-traffic* [unit]
       |  +-- unit                 unit
       |  +-- low-percentile-g?    yang:gauge64
       |  +-- mid-percentile-g?    yang:gauge64
       |  +-- high-percentile-g?   yang:gauge64
       |  +-- peak-g?              yang:gauge64
       +-- attack-detail* [vendor-id attack-id]
          +-- vendor-id             uint32
          +-- attack-id             uint32
          +-- attack-description?   string
          +-- attack-severity?      attack-severity
          +-- start-time?           uint64
          +-- end-time?             uint64

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          +-- source-count
          |  +-- low-percentile-g?    yang:gauge64
          |  +-- mid-percentile-g?    yang:gauge64
          |  +-- high-percentile-g?   yang:gauge64
          |  +-- peak-g?              yang:gauge64
          +-- top-talker
             +-- talker* [source-prefix]
                +-- spoofed-status?            boolean
                +-- source-prefix              inet:ip-prefix
                +-- source-port-range* [lower-port]
                |  +-- lower-port    inet:port-number
                |  +-- upper-port?   inet:port-number
                +-- source-icmp-type-range* [lower-type]
                |  +-- lower-type    uint8
                |  +-- upper-type?   uint8
                +-- total-attack-traffic* [unit]
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-connection
                   +-- low-percentile-c
                   |  +-- connection?           yang:gauge64
                   |  +-- embryonic?            yang:gauge64
                   |  +-- connection-ps?        yang:gauge64
                   |  +-- request-ps?           yang:gauge64
                   |  +-- partial-request-ps?   yang:gauge64
                   +-- mid-percentile-c
                   |  ...
                   +-- high-percentile-c
                   |  ...
                   +-- peak-c
                      ...

            Figure 44: Telemetry Efficacy Update Tree Structure

   In order to signal telemetry data in a mitigation efficacy update, it
   is RECOMMENDED that the DOTS client has already established a DOTS
   telemetry setup session with the server in 'idle' time.

   An example of an efficacy update with telemetry attributes is
   depicted in Figure 45.

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   Header: PUT (Code=0.03)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "mitigate"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "mid=123"
   If-Match:
   Content-Format: "application/dots+cbor"

   {
     "ietf-dots-signal-channel:mitigation-scope": {
       "scope": [
         {
           "alias-name": [
             "https1",
             "https2"
           ],
           "attack-status": "under-attack",
           "ietf-dots-telemetry:total-attack-traffic": [
             {
               "unit": "megabit-ps",
               "mid-percentile-g": "900"
             }
           ]
         }
       ]
     }
   }

    Figure 45: An Example of Mitigation Efficacy Update with Telemetry
                                Attributes

8.2.  DOTS Servers to Clients Mitigation Status DOTS Telemetry
      Attributes

   The mitigation status telemetry attributes can be signaled from the
   DOTS server to the DOTS client as part of the periodic mitigation
   status update (Section 6.3.3 of [I-D.boucadair-dots-rfc8782-bis]).
   In particular, DOTS clients can receive asynchronous notifications of
   the attack details from DOTS servers using the Observe option defined
   in [RFC7641].

   In order to make use of this feature, DOTS clients MUST establish a
   telemetry setup session with the DOTS server in 'idle' time and MUST
   set the 'server-originated-telemetry' attribute to 'true'.

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   DOTS servers MUST NOT include telemetry attributes in mitigation
   status updates sent to DOTS clients for which 'server-originated-
   telemetry' attribute is set to 'false'.

   As defined in [RFC8612], the actual mitigation activities can include
   several countermeasure mechanisms.  The DOTS server signals the
   current operational status of relevant countermeasures.  A list of
   attacks detected by each countermeasure MAY also be included.  The
   same attributes defined in Section 7.1.5 are applicable for
   describing the attacks detected and mitigated at the DOTS server
   domain.

   The "ietf-dots-telemetry" YANG module (Section 10.1) augments the
   'mitigation-scope' message type defined in "ietf-dots-signal"
   [I-D.boucadair-dots-rfc8782-bis] with telemetry data as depicted in
   the following tree structure:

     augment-structure /signal:dots-signal/signal:message-type
                       /signal:mitigation-scope/signal:scope:
       +-- (direction)?
       |  +--:(server-to-client-only)
       |     +-- total-traffic* [unit]
       |     |  +-- unit                 unit
       |     |  +-- low-percentile-g?    yang:gauge64
       |     |  +-- mid-percentile-g?    yang:gauge64
       |     |  +-- high-percentile-g?   yang:gauge64
       |     |  +-- peak-g?              yang:gauge64
       |     +-- total-attack-connection
       |        +-- low-percentile-c
       |        |  +-- connection?           yang:gauge64
       |        |  +-- embryonic?            yang:gauge64
       |        |  +-- connection-ps?        yang:gauge64
       |        |  +-- request-ps?           yang:gauge64
       |        |  +-- partial-request-ps?   yang:gauge64
       |        +-- mid-percentile-c
       |        |  ...
       |        +-- high-percentile-c
       |        |  ...
       |        +-- peak-c
       |           ...
       +-- total-attack-traffic* [unit]
       |  +-- unit                 unit
       |  +-- low-percentile-g?    yang:gauge64
       |  +-- mid-percentile-g?    yang:gauge64
       |  +-- high-percentile-g?   yang:gauge64
       |  +-- peak-g?              yang:gauge64
       +-- attack-detail* [vendor-id attack-id]
          +-- vendor-id             uint32

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          +-- attack-id             uint32
          +-- attack-description?   string
          +-- attack-severity?      attack-severity
          +-- start-time?           uint64
          +-- end-time?             uint64
          +-- source-count
          |  +-- low-percentile-g?    yang:gauge64
          |  +-- mid-percentile-g?    yang:gauge64
          |  +-- high-percentile-g?   yang:gauge64
          |  +-- peak-g?              yang:gauge64
          +-- top-talker
             +-- talker* [source-prefix]
                +-- spoofed-status?            boolean
                +-- source-prefix              inet:ip-prefix
                +-- source-port-range* [lower-port]
                |  +-- lower-port    inet:port-number
                |  +-- upper-port?   inet:port-number
                +-- source-icmp-type-range* [lower-type]
                |  +-- lower-type    uint8
                |  +-- upper-type?   uint8
                +-- total-attack-traffic* [unit]
                |  +-- unit                 unit
                |  +-- low-percentile-g?    yang:gauge64
                |  +-- mid-percentile-g?    yang:gauge64
                |  +-- high-percentile-g?   yang:gauge64
                |  +-- peak-g?              yang:gauge64
                +-- total-attack-connection
                   +-- low-percentile-c
                   |  +-- connection?           yang:gauge64
                   |  +-- embryonic?            yang:gauge64
                   |  +-- connection-ps?        yang:gauge64
                   |  +-- request-ps?           yang:gauge64
                   |  +-- partial-request-ps?   yang:gauge64
                   +-- mid-percentile-c
                   |  ...
                   +-- high-percentile-c
                   |  ...
                   +-- peak-c
                      ...

   Figure 46 shows an example of an asynchronous notification of attack
   mitigation status from the DOTS server.  This notification signals
   both the mid-percentile value of processed attack traffic and the
   peak percentile value of unique sources involved in the attack.

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   {
     "ietf-dots-signal-channel:mitigation-scope": {
       "scope": [
         {
           "mid": 12332,
           "mitigation-start": "1507818434",
           "alias-name": [
             "https1",
             "https2"
           ],
           "lifetime": 1600,
           "status": "attack-successfully-mitigated",
           "bytes-dropped": "134334555",
           "bps-dropped": "43344",
           "pkts-dropped": "333334444",
           "pps-dropped": "432432",
           "ietf-dots-telemetry:total-attack-traffic": [
             {
               "unit": "megabit-ps",
               "mid-percentile-g": "900"
             }
           ],
           "ietf-dots-telemetry:attack-detail": [
             {
               "vendor-id": 1234,
               "attack-id": 77,
               "source-count": {
                 "peak-g": "10000"
               }
             }
           ]
         }
       ]
     }
   }

      Figure 46: Response Body of a Mitigation Status With Telemetry
                                Attributes

   DOTS clients can filter out the asynchronous notifications from the
   DOTS server by indicating one or more Uri-Query options in its GET
   request.  A Uri-Query option can include the following parameters:
   'target-prefix', 'target-port', 'target-protocol', 'target-fqdn',
   'target-uri', 'alias-name', and 'c' (content) (Section 4.2.4).  The
   considerations discussed in Section 7.3 MUST be followed to include
   multiple query values, ranges ('target-port', 'target-protocol'), and
   wildcard name ('target-fqdn', 'target-uri').

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   An example of request to subscribe to asynchronous notifications
   bound to the "http1" alias is shown in Figure 47.

   Header: GET (Code=0.01)
   Uri-Path: ".well-known"
   Uri-Path: "dots"
   Uri-Path: "mitigate"
   Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
   Uri-Path: "mid=12332"
   Uri-Query: "target-alias=https1"
   Observe: 0

   Figure 47: GET Request to Receive Asynchronous Notifications Filtered
                              using Uri-Query

   If the target query does not match the target of the enclosed 'mid'
   as maintained by the DOTS server, the latter MUST respond with a 4.04
   (Not Found) error Response Code.  The DOTS server MUST NOT add a new
   observe entry if this query overlaps with an existing one.

9.  Error Handling

   A list of common CoAP errors that are implemented by DOTS servers are
   provided in Section 6 of [I-D.boucadair-dots-rfc8782-bis].  The
   following additional error cases apply for the telemetry extension:

   o  4.00 (Bad Request) is returned by the DOTS server when the DOTS
      client has sent a request that violates the DOTS telemetry
      extension.

   o  4.04 (Not Found) is returned by the DOTS server when the DOTS
      client is requesting a 'tsid' or 'tmid' that is not valid.

   o  4.00 (Bad Request) is returned by the DOTS server when the DOTS
      client has sent a request with invalid query types (e.g., not
      supported, malformed).

   o  4.04 (Not Found) is returned by the DOTS server when the DOTS
      client has sent a request with a target query that does not match
      the target of the enclosed 'mid' as maintained by the DOTS server.

10.  YANG Modules

10.1.  DOTS Signal Channel Telemetry YANG Module

   This module uses types defined in [RFC6991] and [RFC8345].

 <CODE BEGINS> file "ietf-dots-telemetry@2020-07-03.yang"

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 module ietf-dots-telemetry {
   yang-version 1.1;
   namespace "urn:ietf:params:xml:ns:yang:ietf-dots-telemetry";
   prefix dots-telemetry;

   import ietf-dots-signal-channel {
     prefix signal;
     reference
       "RFC UUUU: Distributed Denial-of-Service Open Threat Signaling
                  (DOTS) Signal Channel Specification";
   }
   import ietf-dots-data-channel {
     prefix ietf-data;
     reference
       "RFC 8783: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Data Channel Specification";
   }
   import ietf-yang-types {
     prefix yang;
     reference
       "Section 3 of RFC 6991";
   }
   import ietf-inet-types {
     prefix inet;
     reference
       "Section 4 of RFC 6991";
   }
   import ietf-network-topology {
     prefix nt;
     reference
       "Section 6.2 of RFC 8345: A YANG Data Model for Network
        Topologies";
   }
   import ietf-yang-structure-ext {
     prefix sx;
     reference
       "RFC 8791: YANG Data Structure Extensions";
   }

   organization
     "IETF DDoS Open Threat Signaling (DOTS) Working Group";
   contact
     "WG Web:   <https://datatracker.ietf.org/wg/dots/>
      WG List:  <mailto:dots@ietf.org>

      Author:  Mohamed Boucadair
               <mailto:mohamed.boucadair@orange.com>

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      Author:  Konda, Tirumaleswar Reddy
               <mailto:TirumaleswarReddy_Konda@McAfee.com>";
   description
     "This module contains YANG definitions for the signaling
      of DOTS telemetry exchanged between a DOTS client and
      a DOTS server by means of the DOTS signal channel.

      Copyright (c) 2020 IETF Trust and the persons identified as
      authors of the code.  All rights reserved.

      Redistribution and use in source and binary forms, with or
      without modification, is permitted pursuant to, and subject
      to the license terms contained in, the Simplified BSD License
      set forth in Section 4.c of the IETF Trust's Legal Provisions
      Relating to IETF Documents
      (http://trustee.ietf.org/license-info).

      This version of this YANG module is part of RFC XXXX; see
      the RFC itself for full legal notices.";

   revision 2020-07-03 {
     description
       "Initial revision.";
     reference
       "RFC XXXX: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Telemetry";
   }

   typedef attack-severity {
     type enumeration {
       enum none {
         value 1;
         description
           "No effect on the DOTS client domain.";
       }
       enum low {
         value 2;
         description
           "Minimal effect on the DOTS client domain.";
       }
       enum medium {
         value 3;
         description
           "A subset of DOTS client domain resources are
            out of service.";
       }
       enum high {
         value 4;

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         description
           "The DOTS client domain is under extremly severe
            conditions.";
       }
       enum unknown {
         value 5;
         description
           "The impact of the attack is not known.";
       }
     }
     description
       "Enumeration for attack severity.";
     reference
       "RFC 7970: The Incident Object Description Exchange
                  Format Version 2";
   }

   typedef unit-type {
     type enumeration {
       enum packet-ps {
         value 1;
         description
           "Packets per second (pps).";
       }
       enum bit-ps {
         value 2;
         description
           "Bits per Second (bit/s).";
       }
       enum byte-ps {
         value 3;
         description
           "Bytes per second (Byte/s).";
       }
     }
     description
       "Enumeration to indicate which unit type is used.";
   }

   typedef unit {
     type enumeration {
       enum packet-ps {
         value 1;
         description
           "Packets per second (pps).";
       }
       enum bit-ps {
         value 2;

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         description
           "Bits per Second (bps).";
       }
       enum byte-ps {
         value 3;
         description
           "Bytes per second (Bps).";
       }
       enum kilopacket-ps {
         value 4;
         description
           "Kilo packets per second (kpps).";
       }
       enum kilobit-ps {
         value 5;
         description
           "Kilobits per second (kbps).";
       }
       enum kilobyte-ps {
         value 6;
         description
           "Kilobytes per second (kBps).";
       }
       enum megapacket-ps {
         value 7;
         description
           "Mega packets per second (Mpps).";
       }
       enum megabit-ps {
         value 8;
         description
           "Megabits per second (Mbps).";
       }
       enum megabyte-ps {
         value 9;
         description
           "Megabytes per second (MBps).";
       }
       enum gigapacket-ps {
         value 10;
         description
           "Giga packets per second (Gpps).";
       }
       enum gigabit-ps {
         value 11;
         description
           "Gigabits per second (Gbps).";
       }

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       enum gigabyte-ps {
         value 12;
         description
           "Gigabytes per second (GBps).";
       }
       enum terapacket-ps {
         value 13;
         description
           "Tera packets per second (Tpps).";
       }
       enum terabit-ps {
         value 14;
         description
           "Terabits per second (Tbps).";
       }
       enum terabyte-ps {
         value 15;
         description
           "Terabytes per second (TBps).";
       }
     }
     description
       "Enumeration to indicate which unit is used.";
   }

   typedef interval {
     type enumeration {
       enum hour {
         value 1;
         description
           "Hour.";
       }
       enum day {
         value 2;
         description
           "Day.";
       }
       enum week {
         value 3;
         description
           "Week.";
       }
       enum month {
         value 4;
         description
           "Month.";
       }
     }

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     description
       "Enumeration to indicate the overall measurement period.";
   }

   typedef sample {
     type enumeration {
       enum second {
         value 1;
         description
           " A one second measurement period.";
       }
       enum 5-seconds {
         value 2;
         description
           "5 seconds measurement period.";
       }
       enum 30-seconds {
         value 3;
         description
           "30 seconds measurement period.";
       }
       enum minute {
         value 4;
         description
           "One minute measurement period.";
       }
       enum 5-minutes {
         value 5;
         description
           "5 minutes measurement period.";
       }
       enum 10-minutes {
         value 6;
         description
           "10 minutes measurement period.";
       }
       enum 30-minutes {
         value 7;
         description
           "30 minutes measurement period.";
       }
       enum hour {
         value 8;
         description
           "One hour measurement period.";
       }
     }
     description

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       "Enumeration to indicate the measurement period.";
   }

   typedef percentile {
     type decimal64 {
       fraction-digits 2;
     }
     description
       "The nth percentile of a set of data is the
        value at which n percent of the data is below it.";
   }

   typedef query-type {
     type enumeration {
       enum target-prefix {
         value 1;
         description
           "Query based on target prefix.";
       }
       enum target-port {
         value 2;
         description
           "Query based on target port number.";
       }
       enum target-protocol {
         value 3;
         description
           "Query based on target protocol.";
       }
       enum target-fqdn {
         value 4;
         description
           "Query based on target FQDN.";
       }
       enum target-uri {
         value 5;
         description
           "Query based on target URI.";
       }
       enum target-alias {
         value 6;
         description
           "Query based on target alias.";
       }
       enum mid {
         value 7;
         description
           "Query based on mitigation identifier (mid).";

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       }
       enum source-prefix {
         value 8;
         description
           "Query based on source prefix.";
       }
       enum source-port {
         value 9;
         description
           "Query based on source port number.";
       }
       enum source-icmp-type {
         value 10;
         description
           "Query based on ICMP type";
       }
       enum content {
         value 11;
         description
           "Query based on 'c' Uri-Query option that is used
            to control the selection of configuration
             and non-configuration data nodes.";
         reference
           "Section 4.4.2 of RFC 8782.";
       }
     }
     description
       "Enumeration support for query types that can be used
        in a GET request to filter out data.";
   }

   grouping percentile-config {
     description
       "Configuration of low, mid, and high percentile values.";
     leaf measurement-interval {
       type interval;
       description
         "Defines the period on which percentiles are computed.";
     }
     leaf measurement-sample {
       type sample;
       description
         "Defines the time distribution for measuring
          values that are used to compute percentiles.";
     }
     leaf low-percentile {
       type percentile;
       default "10.00";

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       description
         "Low percentile. If set to '0', this means low-percentiles
          are disabled.";
     }
     leaf mid-percentile {
       type percentile;
       must '. >= ../low-percentile' {
         error-message
           "The mid-percentile must be greater than
            or equal to the low-percentile.";
       }
       default "50.00";
       description
         "Mid percentile. If set to the same value as low-percentiles,
          this means mid-percentiles are disabled.";
     }
     leaf high-percentile {
       type percentile;
       must '. >= ../mid-percentile' {
         error-message
           "The high-percentile must be greater than
            or equal to the mid-percentile.";
       }
       default "90.00";
       description
         "High percentile. If set to the same value as mid-percentiles,
          this means high-percentiles are disabled.";
     }
   }

   grouping percentile {
     description
       "Generic grouping for percentile.";
     leaf low-percentile-g {
       type yang:gauge64;
       description
         "Low percentile value.";
     }
     leaf mid-percentile-g {
       type yang:gauge64;
       description
         "Mid percentile value.";
     }
     leaf high-percentile-g {
       type yang:gauge64;
       description
         "High percentile value.";
     }

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     leaf peak-g {
       type yang:gauge64;
       description
         "Peak value.";
     }
   }

   grouping unit-config {
     description
       "Generic grouping for unit configuration.";
     list unit-config {
       key "unit";
       description
         "Controls which unit types are allowed when sharing
          telemetry data.";
       leaf unit {
         type unit-type;
         description
           "Can be packet-ps, bit-ps, or byte-ps.";
       }
       leaf unit-status {
         type boolean;
         mandatory true;
         description
           "Enable/disable the use of the measurement unit type.";
       }
     }
   }

   grouping traffic-unit {
     description
       "Grouping of traffic as a function of the measurement unit.";
     leaf unit {
       type unit;
       description
         "The traffic can be measured using unit types: packet-ps,
          bit-ps, or byte-ps. DOTS agents auto-scale to the appropriate
          units (e.g., megabit-ps, kilobit-ps).";
     }
     uses percentile;
   }

   grouping traffic-unit-protocol {
     description
       "Grouping of traffic of a given transport protocol as
        a function of the measurement unit.";
     leaf protocol {
       type uint8;

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       description
         "The transport protocol.
          Values are taken from the IANA Protocol Numbers registry:
          <https://www.iana.org/assignments/protocol-numbers/>.

          For example, this parameter contains 6 for TCP,
          17 for UDP, 33 for DCCP, or 132 for SCTP.";
     }
     uses traffic-unit;
   }

   grouping traffic-unit-port {
     description
       "Grouping of traffic bound to a port number as
        a function of the measurement unit.";
     leaf port {
       type inet:port-number;
       description
         "Port number.";
     }
     uses traffic-unit;
   }

   grouping total-connection-capacity {
     description
       "Total Connections Capacity. These data nodes are
        useful to detect resource consuming DDoS attacks";
     leaf connection {
       type uint64;
       description
         "The maximum number of simultaneous connections that
          are allowed to the target server.";
     }
     leaf connection-client {
       type uint64;
       description
         "The maximum number of simultaneous connections that
          are allowed to the target server per client.";
     }
     leaf embryonic {
       type uint64;
       description
         "The maximum number of simultaneous embryonic connections
          that are allowed to the target server. The term 'embryonic
          connection' refers to a connection whose connection handshake
          is not finished. Embryonic connection is only possible in
          connection-oriented transport protocols like TCP or SCTP.";
     }

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     leaf embryonic-client {
       type uint64;
       description
         "The maximum number of simultaneous embryonic connections
          that are allowed to the target server per client.";
     }
     leaf connection-ps {
       type uint64;
       description
         "The maximum number of connections allowed per second
          to the target server.";
     }
     leaf connection-client-ps {
       type uint64;
       description
         "The maximum number of connections allowed per second
          to the target server per client.";
     }
     leaf request-ps {
       type uint64;
       description
         "The maximum number of requests allowed per second
          to the target server.";
     }
     leaf request-client-ps {
       type uint64;
       description
         "The maximum number of requests allowed per second
          to the target server per client.";
     }
     leaf partial-request-ps {
       type uint64;
       description
         "The maximum number of partial requests allowed per
          second to the target server.";
     }
     leaf partial-request-client-ps {
       type uint64;
       description
         "The maximum number of partial requests allowed per
          second to the target server per client.";
     }
   }

   grouping total-connection-capacity-protocol {
     description
       "Total Connections Capacity per protocol. These data nodes are
        useful to detect resource consuming DDoS attacks.";

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     leaf protocol {
       type uint8;
       description
         "The transport protocol.
          Values are taken from the IANA Protocol Numbers registry:
          <https://www.iana.org/assignments/protocol-numbers/>.";
     }
     uses total-connection-capacity;
   }

   grouping connection {
     description
       "A set of data nodes which represent the attack
        characteristics";
     leaf connection {
       type yang:gauge64;
       description
         "The number of simultaneous attack connections to
          the target server.";
     }
     leaf embryonic {
       type yang:gauge64;
       description
         "The number of simultaneous embryonic connections to
          the target server.";
     }
     leaf connection-ps {
       type yang:gauge64;
       description
         "The number of attack connections per second to
          the target server.";
     }
     leaf request-ps {
       type yang:gauge64;
       description
         "The number of attack requests per second to
          the target server.";
     }
     leaf partial-request-ps {
       type yang:gauge64;
       description
         "The number of attack partial requests to
          the target server.";
     }
   }

   grouping connection-percentile {
     description

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       "Total attack connections.";
     container low-percentile-c {
       description
         "Low percentile of attack connections.";
       uses connection;
     }
     container mid-percentile-c {
       description
         "Mid percentile of attack connections.";
       uses connection;
     }
     container high-percentile-c {
       description
         "High percentile of attack connections.";
       uses connection;
     }
     container peak-c {
       description
         "Peak attack connections.";
       uses connection;
     }
   }

   grouping connection-protocol {
     description
       "Total attack connections.";
     leaf protocol {
       type uint8;
       description
         "The transport protocol.
          Values are taken from the IANA Protocol Numbers registry:
          <https://www.iana.org/assignments/protocol-numbers/>.";
     }
     uses connection;
   }

   grouping connection-port {
     description
       "Total attack connections per port number.";
     leaf port {
       type inet:port-number;
       description
         "Port number.";
     }
     uses connection-protocol;
   }

   grouping connection-protocol-percentile {

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     description
       "Total attack connections per protocol.";
     list low-percentile-l {
       key "protocol";
       description
         "Low percentile of attack connections per protocol.";
       uses connection-protocol;
     }
     list mid-percentile-l {
       key "protocol";
       description
         "Mid percentile of attack connections per protocol.";
       uses connection-protocol;
     }
     list high-percentile-l {
       key "protocol";
       description
         "High percentile of attack connections per protocol.";
       uses connection-protocol;
     }
     list peak-l {
       key "protocol";
       description
         "Peak attack connections per protocol.";
       uses connection-protocol;
     }
   }

   grouping connection-protocol-port-percentile {
     description
       "Total attack connections per port number.";
     list low-percentile-l {
       key "protocol port";
       description
         "Low percentile of attack connections per port number.";
       uses connection-port;
     }
     list mid-percentile-l {
       key "protocol port";
       description
         "Mid percentile of attack connections per port number.";
       uses connection-port;
     }
     list high-percentile-l {
       key "protocol port";
       description
         "High percentile of attack connections per port number.";
       uses connection-port;

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     }
     list peak-l {
       key "protocol port";
       description
         "Peak attack connections per port number.";
       uses connection-port;
     }
   }

   grouping attack-detail {
     description
       "Various details that describe the on-going
        attacks that need to be mitigated by the DOTS server.
        The attack details need to cover well-known and common attacks
        (such as a SYN Flood) along with new emerging or vendor-specific
        attacks.";
     leaf vendor-id {
       type uint32;
       description
         "Vendor ID is a security vendor's Enterprise Number.";
     }
     leaf attack-id {
       type uint32;
       description
         "Unique identifier assigned by the vendor for the attack.";
     }
     leaf attack-description {
       type string;
       description
         "Textual representation of attack description. Natural Language
          Processing techniques (e.g., word embedding) can possibly be
          used to map the attack description to an attack type.";
     }
     leaf attack-severity {
       type attack-severity;
       description
         "Severity level of an attack. How this level is determined
          is implementation-specific.";
     }
     leaf start-time {
       type uint64;
       description
         "The time the attack started. Start time is represented in
          seconds relative to 1970-01-01T00:00:00Z in UTC time.";
     }
     leaf end-time {
       type uint64;
       description

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         "The time the attack ended. End time is represented in seconds
          relative to 1970-01-01T00:00:00Z in UTC time.";
     }
     container source-count {
       description
         "Indicates the count of unique sources involved
          in the attack.";
       uses percentile;
     }
   }

   grouping top-talker-aggregate {
     description
       "Top attack sources.";
     list talker {
       key "source-prefix";
       description
         "IPv4 or IPv6 prefix identifying the attacker(s).";
       leaf spoofed-status {
         type boolean;
         description
           "Indicates whether this address is spoofed.";
       }
       leaf source-prefix {
         type inet:ip-prefix;
         description
           "IPv4 or IPv6 prefix identifying the attacker(s).";
       }
       list source-port-range {
         key "lower-port";
         description
           "Port range. When only lower-port is
            present, it represents a single port number.";
         leaf lower-port {
           type inet:port-number;
           mandatory true;
           description
             "Lower port number of the port range.";
         }
         leaf upper-port {
           type inet:port-number;
           must '. >= ../lower-port' {
             error-message
               "The upper port number must be greater than
                or equal to lower port number.";
           }
           description
             "Upper port number of the port range.";

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         }
       }
       list source-icmp-type-range {
         key "lower-type";
         description
           "ICMP type range. When only lower-type is
            present, it represents a single ICMP type.";
         leaf lower-type {
           type uint8;
           mandatory true;
           description
             "Lower ICMP type of the ICMP type range.";
         }
         leaf upper-type {
           type uint8;
           must '. >= ../lower-type' {
             error-message
               "The upper ICMP type must be greater than
                or equal to lower ICMP type.";
           }
           description
             "Upper type of the ICMP type range.";
         }
       }
       list total-attack-traffic {
         key "unit";
         description
           "Total attack traffic issued from this source.";
         uses traffic-unit;
       }
       container total-attack-connection {
         description
           "Total attack connections issued from this source.";
         uses connection-percentile;
       }
     }
   }

   grouping top-talker {
     description
       "Top attack sources.";
     list talker {
       key "source-prefix";
       description
         "IPv4 or IPv6 prefix identifying the attacker(s).";
       leaf spoofed-status {
         type boolean;
         description

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           "Indicates whether this address is spoofed.";
       }
       leaf source-prefix {
         type inet:ip-prefix;
         description
           "IPv4 or IPv6 prefix identifying the attacker(s).";
       }
       list source-port-range {
         key "lower-port";
         description
           "Port range. When only lower-port is
            present, it represents a single port number.";
         leaf lower-port {
           type inet:port-number;
           mandatory true;
           description
             "Lower port number of the port range.";
         }
         leaf upper-port {
           type inet:port-number;
           must '. >= ../lower-port' {
             error-message
               "The upper port number must be greater than
                or equal to lower port number.";
           }
           description
             "Upper port number of the port range.";
         }
       }
       list source-icmp-type-range {
         key "lower-type";
         description
           "ICMP type range. When only lower-type is
            present, it represents a single ICMP type.";
         leaf lower-type {
           type uint8;
           mandatory true;
           description
             "Lower ICMP type of the ICMP type range.";
         }
         leaf upper-type {
           type uint8;
           must '. >= ../lower-type' {
             error-message
               "The upper ICMP type must be greater than
                or equal to lower ICMP type.";
           }
           description

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             "Upper type of the ICMP type range.";
         }
       }
       list total-attack-traffic {
         key "unit";
         description
           "Total attack traffic issued from this source.";
         uses traffic-unit;
       }
       container total-attack-connection {
         description
           "Total attack connections issued from this source.";
         uses connection-protocol-percentile;
       }
     }
   }

   grouping baseline {
     description
       "Grouping for the telemetry baseline.";
     uses ietf-data:target;
     leaf-list alias-name {
       type string;
       description
         "An alias name that points to a resource.";
     }
     list total-traffic-normal {
       key "unit";
       description
         "Total traffic normal baselines.";
       uses traffic-unit;
     }
     list total-traffic-normal-per-protocol {
       key "unit protocol";
       description
         "Total traffic normal baselines per protocol.";
       uses traffic-unit-protocol;
     }
     list total-traffic-normal-per-port {
       key "unit port";
       description
         "Total traffic normal baselines per port number.";
       uses traffic-unit-port;
     }
     list total-connection-capacity {
       key "protocol";
       description
         "Total connection capacity.";

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       uses total-connection-capacity-protocol;
     }
     list total-connection-capacity-per-port {
       key "protocol port";
       description
         "Total connection capacity per port number.";
       leaf port {
         type inet:port-number;
         description
           "The target port number.";
       }
       uses total-connection-capacity-protocol;
     }
   }

   grouping pre-or-ongoing-mitigation {
     description
       "Grouping for the telemetry data.";
     list total-traffic {
       key "unit";
       description
         "Total traffic.";
       uses traffic-unit;
     }
     list total-traffic-protocol {
       key "unit protocol";
       description
         "Total traffic per protocol.";
       uses traffic-unit-protocol;
     }
     list total-traffic-port {
       key "unit port";
       description
         "Total traffic per port.";
       uses traffic-unit-port;
     }
     list total-attack-traffic {
       key "unit";
       description
         "Total attack traffic.";
       uses traffic-unit-protocol;
     }
     list total-attack-traffic-protocol {
       key "unit protocol";
       description
         "Total attack traffic per protocol.";
       uses traffic-unit-protocol;
     }

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     list total-attack-traffic-port {
       key "unit port";
       description
         "Total attack traffic per port.";
       uses traffic-unit-port;
     }
     container total-attack-connection {
       description
         "Total attack connections.";
       uses connection-protocol-percentile;
     }
     container total-attack-connection-port {
       description
         "Total attack connections.";
       uses connection-protocol-port-percentile;
     }
     list attack-detail {
       key "vendor-id attack-id";
       description
         "Provides a set of attack details.";
       uses attack-detail;
       container top-talker {
         description
           "Lists the top attack sources.";
         uses top-talker;
       }
     }
   }

   sx:augment-structure "/signal:dots-signal/signal:message-type/"
                      + "signal:mitigation-scope/signal:scope" {
     description
       "Extends mitigation scope with telemetry update data.";
     choice direction {
       description
         "Indicates the communication direction in which the
          data nodes can be included.";
       case server-to-client-only {
         description
           "These data nodes appear only in a mitigation message
            sent from the server to the client.";
         list total-traffic {
           key "unit";
           description
             "Total traffic.";
           uses traffic-unit;
         }
         container total-attack-connection {

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           description
             "Total attack connections.";
           uses connection-percentile;
         }
       }
     }
     list total-attack-traffic {
       key "unit";
       description
         "Total attack traffic.";
       uses traffic-unit;
     }
     list attack-detail {
       key "vendor-id attack-id";
       description
         "Attack details";
       uses attack-detail;
       container top-talker {
         description
           "Top attack sources.";
         uses top-talker-aggregate;
       }
     }
   }
   sx:structure dots-telemetry {
     description
       "Main structure for DOTS telemetry messages.";
     choice telemetry-message-type {
       description
         "Can be a telemetry-setup or telemetry data.";
       case telemetry-setup {
         description
           "Indicates the message is about telemetry.";
         choice direction {
           description
             "Indicates the communication direction in which the
              data nodes can be included.";
           case server-to-client-only {
             description
               "These data nodes appear only in a mitigation message
                sent from the server to the client.";
             container max-config-values {
               description
                 "Maximum acceptable configuration values.";
               uses percentile-config;
               leaf server-originated-telemetry {
                 type boolean;
                 description

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                   "Indicates whether the DOTS server can be instructed
                    to send pre-or-ongoing-mitigation telemetry. If set
                    to FALSE or the data node is not present, this is
                    an indication that the server does not support this
                    capability.";
               }
               leaf telemetry-notify-interval {
                 type uint32 {
                   range "1 .. 3600";
                 }
                 must ". >= ../../min-config-values"
                    + "/telemetry-notify-interval" {
                   error-message
                     "The value must be greater than or equal
                      to the telemetry-notify-interval in the
                      min-config-values";
                 }
                 units "seconds";
                 description
                   "Minimum number of seconds between successive
                    telemetry notifications.";
               }
             }
             container min-config-values {
               description
                 "Minimum acceptable configuration values.";
               uses percentile-config;
               leaf telemetry-notify-interval {
                 type uint32 {
                   range "1 .. 3600";
                 }
                 units "seconds";
                 description
                   "Minimum number of seconds between successive
                    telemetry notifications.";
               }
             }
             container supported-units {
               description
                 "Supported units and default activation status.";
               uses unit-config;
             }
             leaf-list query-type {
               type query-type;
               description
                 "Indicates which query types are supported by
                  the server.";
             }

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           }
         }
         list telemetry {
           description
             "The telemetry data per DOTS client.";
           choice direction {
             description
               "Indicates the communication direction in which the
                data nodes can be included.";
             case server-to-client-only {
               description
                 "These data nodes appear only in a mitigation message
                  sent from the server to the client.";
               leaf tsid {
                 type uint32;
                 description
                   "An identifier for the DOTS telemetry setup
                    data.";
               }
             }
           }
           choice setup-type {
             description
               "Can be a mitigation configuration, a pipe capacity,
                or baseline message.";
             case telemetry-config {
               description
                 "Uses to set low, mid, and high percentile values.";
               container current-config {
                 description
                   "Current configuration values.";
                 uses percentile-config;
                 uses unit-config;
                 leaf server-originated-telemetry {
                   type boolean;
                   description
                     "Used by a DOTS client to enable/disable whether it
                      accepts pre-or-ongoing-mitigation telemetry from
                      the DOTS server.";
                 }
                 leaf telemetry-notify-interval {
                   type uint32 {
                     range "1 .. 3600";
                   }
                   units "seconds";
                   description
                     "Minimum number of seconds between successive
                      telemetry notifications.";

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                 }
               }
             }
             case pipe {
               description
                 "Total pipe capacity of a DOTS client domain";
               list total-pipe-capacity {
                 key "link-id unit";
                 description
                   "Total pipe capacity of a DOTS client domain.";
                 leaf link-id {
                   type nt:link-id;
                   description
                     "Identifier of an interconnection link.";
                 }
                 leaf capacity {
                   type uint64;
                   mandatory true;
                   description
                     "Pipe capacity.";
                 }
                 leaf unit {
                   type unit;
                   description
                     "The traffic can be measured using unit types:
                      packets per second (PPS), Bits per Second (BPS),
                      and/or bytes per second. DOTS agents auto-scale
                      to the appropriate units (e.g., megabit-ps,
                      kilobit-ps).";
                 }
               }
             }
             case baseline {
               description
                 "Traffic baseline information";
               list baseline {
                 key "id";
                 description
                   "Traffic baseline information";
                 leaf id {
                   type uint32;
                   must '. >= 1';
                   description
                     "A baseline entry identifier.";
                 }
                 uses baseline;
               }
             }

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           }
         }
       }
       case telemetry {
         description
           "Indicates the message is about telemetry.";
         list pre-or-ongoing-mitigation {
           description
             "Pre-or-ongoing-mitigation telemetry per DOTS client.";
           choice direction {
             description
               "Indicates the communication direction in which the
                data nodes can be included.";
             case server-to-client-only {
               description
                 "These data nodes appear only in a mitigation message
                  sent from the server to the client.";
               leaf tmid {
                 type uint32;
                 description
                   "An identifier to uniquely demux telemetry data sent
                    using the same message.";
               }
             }
           }
           container target {
             description
               "Indicates the target.";
             uses ietf-data:target;
             leaf-list alias-name {
               type string;
               description
                 "An alias name that points to a resource.";
             }
             leaf-list mid-list {
               type uint32;
               description
                 "Reference a list of associated mitigation requests.";
             }
           }
           uses pre-or-ongoing-mitigation;
         }
       }
     }
   }
 }
 <CODE ENDS>

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10.2.  Vendor Attack Mapping Details YANG Module

 <CODE BEGINS> file "ietf-dots-mapping@2020-06-26.yang"
 module ietf-dots-mapping {
   yang-version 1.1;
   namespace "urn:ietf:params:xml:ns:yang:ietf-dots-mapping";
   prefix dots-mapping;

   import ietf-dots-data-channel {
     prefix ietf-data;
     reference
       "RFC 8783: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Data Channel Specification";
   }

   organization
     "IETF DDoS Open Threat Signaling (DOTS) Working Group";
   contact
     "WG Web:   <https://datatracker.ietf.org/wg/dots/>
      WG List:  <mailto:dots@ietf.org>

      Author:  Mohamed Boucadair
               <mailto:mohamed.boucadair@orange.com>

      Author:  Jon Shallow
               <mailto:supjps-ietf@jpshallow.com>";
   description
     "This module contains YANG definitions for the sharing
      DDoS attack mapping details between a DOTS client and
      a DOTS server, by means of the DOTS data channel.

      Copyright (c) 2020 IETF Trust and the persons identified as
      authors of the code.  All rights reserved.

      Redistribution and use in source and binary forms, with or
      without modification, is permitted pursuant to, and subject
      to the license terms contained in, the Simplified BSD License
      set forth in Section 4.c of the IETF Trust's Legal Provisions
      Relating to IETF Documents
      (http://trustee.ietf.org/license-info).

      This version of this YANG module is part of RFC XXXX; see
      the RFC itself for full legal notices.";

   revision 2020-06-26 {
     description
       "Initial revision.";
     reference

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       "RFC XXXX: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Telemetry";
   }

   feature dots-telemetry {
     description
       "This feature indicates that DOTS telemetry data can be
        shared between DOTS clients and servers.";
   }

   grouping attack-mapping {
     description
       "A set of information used for sharing vendor attack mapping
        information with a peer.";
     list vendor {
       key "vendor-id";
       description
         "Vendor attack mapping information of the client/server";
       leaf vendor-id {
         type uint32;
         description
           "Vendor ID is a security vendor's Enterprise Number.";
       }
       leaf vendor-name {
         type string;
         description
           "The name of the vendor (e.g., company A).";
       }
       leaf last-updated {
         type uint64;
         mandatory true;
         description
           "The time the mapping table was updated. It is represented
             in seconds relative to 1970-01-01T00:00:00Z in UTC time.";
       }
       list attack-mapping {
         key "attack-id";
         description
           "Attack mapping details.";
         leaf attack-id {
           type uint32;
           description
             "Unique identifier assigned by the vendor for the attack.";
         }
         leaf attack-description {
           type string;
           mandatory true;
           description

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             "Textual representation of attack description. Natural
              Language Processing techniques (e.g., word embedding)
              can possibly be used to map the attack description to
              an attack type.";
         }
       }
     }
   }

   augment "/ietf-data:dots-data/ietf-data:dots-client" {
     if-feature "dots-telemetry";
     description
       "Augments the data channel with a vendor attack
        mapping table of the DOTS client.";
     container vendor-mapping {
       description
         "Used by DOTS clients to share their vendor
          attack mapping information with DOTS servers.";
       uses attack-mapping;
     }
   }

   augment "/ietf-data:dots-data/ietf-data:capabilities" {
     if-feature "dots-telemetry";
     description
       "Augments the DOTS server capabilities with a
        parameter to indicate whether they can share
        attack mapping details.";
     leaf vendor-mapping-enabled {
       type boolean;
       config false;
       description
         "Indicates that the server supports sharing
          attack vendor mapping details with DOTS clients.";
     }
   }

   augment "/ietf-data:dots-data" {
     if-feature "dots-telemetry";
     description
       "Augments the data channel with a vendor attack
        mapping table of the DOTS server.";
     container vendor-mapping {
       config false;
       description
         "Includes the list of vendor attack mapping details
          that will be shared upon request with DOTS clients.";
       uses attack-mapping;

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     }
   }
 }
 <CODE ENDS>

11.  YANG/JSON Mapping Parameters to CBOR

   All DOTS telemetry parameters in the payload of the DOTS signal
   channel MUST be mapped to CBOR types as shown in the following table:

   o  Implementers may use the values in: https://github.com/boucadair/
      draft-dots-telemetry/blob/master/mapping-table.txt

  +----------------------+-------------+------+---------------+--------+
  | Parameter Name       | YANG        | CBOR | CBOR Major    | JSON   |
  |                      | Type        | Key  |    Type &     | Type   |
  |                      |             |      | Information   |        |
  +======================+=============+======+===============+========+
  | tsid                 | uint32      |TBA1  | 0 unsigned    | Number |
  | telemetry            | container   |TBA2  | 5 map         | Object |
  | low-percentile       | decimal64   |TBA3  | 6 tag 4       |        |
  |                      |             |      |  [-2, integer]| String |
  | mid-percentile       | decimal64   |TBA4  | 6 tag 4       |        |
  |                      |             |      |  [-2, integer]| String |
  | high-percentile      | decimal64   |TBA5  | 6 tag 4       |        |
  |                      |             |      |  [-2, integer]| String |
  | unit-config          | list        |TBA6  | 4 array       | Array  |
  | unit                 | enumeration |TBA7  | 0 unsigned    | String |
  | unit-status          | boolean     |TBA8  | 7 bits 20     | False  |
  |                      |             |      | 7 bits 21     | True   |
  | total-pipe-capability| list        |TBA9  | 4 array       | Array  |
  | link-id              | string      |TBA10 | 3 text string | String |
  | pre-or-ongoing-      | list        |TBA11 | 4 array       | Array  |
  |      mitigation      |             |      |               |        |
  | total-traffic-normal | list        |TBA12 | 4 array       | Array  |
  | low-percentile-g     | yang:gauge64|TBA13 | 0 unsigned    | String |
  | mid-percentile-g     | yang:gauge64|TBA14 | 0 unsigned    | String |
  | high-percentile-g    | yang:gauge64|TBA15 | 0 unsigned    | String |
  | peak-g               | yang:gauge64|TBA16 | 0 unsigned    | String |
  | total-attack-traffic | list        |TBA17 | 4 array       | Array  |
  | total-traffic        | list        |TBA18 | 4 array       | Array  |
  | total-connection-    |             |      |               |        |
  |        capacity      | list        |TBA19 | 4 array       | Array  |
  | connection           | uint64      |TBA20 | 0 unsigned    | String |
  | connection-client    | uint64      |TBA21 | 0 unsigned    | String |
  | embryonic            | uint64      |TBA22 | 0 unsigned    | String |
  | embryonic-client     | uint64      |TBA23 | 0 unsigned    | String |
  | connection-ps        | uint64      |TBA24 | 0 unsigned    | String |

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  | connection-client-ps | uint64      |TBA25 | 0 unsigned    | String |
  | request-ps           | uint64      |TBA26 | 0 unsigned    | String |
  | request-client-ps    | uint64      |TBA27 | 0 unsigned    | String |
  | partial-request-ps   | uint64      |TBA28 | 0 unsigned    | String |
  | partial-request-     |             |      |               |        |
  |        client-ps     | uint64      |TBA29 | 0 unsigned    | String |
  | total-attack-        |             |      |               |        |
  |        connection    | container   |TBA30 | 5 map         | Object |
  | low-percentile-l     | list        |TBA31 | 4 array       | Array  |
  | mid-percentile-l     | list        |TBA32 | 4 array       | Array  |
  | high-percentile-l    | list        |TBA33 | 4 array       | Array  |
  | peak-l               | list        |TBA34 | 4 array       | Array  |
  | attack-detail        | list        |TBA35 | 4 array       | Array  |
  | id                   | uint32      |TBA36 | 0 unsigned    | Number |
  | attack-id            | uint32      |TBA37 | 0 unsigned    | Number |
  | attack-description   | string      |TBA38 | 3 text string | String |
  | attack-severity      | enumeration |TBA39 | 0 unsigned    | String |
  | start-time           | uint64      |TBA40 | 0 unsigned    | String |
  | end-time             | uint64      |TBA41 | 0 unsigned    | String |
  | source-count         | container   |TBA42 | 5 map         | Object |
  | top-talker           | container   |TBA43 | 5 map         | Object |
  | spoofed-status       | boolean     |TBA44 | 7 bits 20     | False  |
  |                      |             |      | 7 bits 21     | True   |
  | low-percentile-c     | container   |TBA45 | 5 map         | Object |
  | mid-percentile-c     | container   |TBA46 | 5 map         | Object |
  | high-percentile-c    | container   |TBA47 | 5 map         | Object |
  | peak-c               | container   |TBA48 | 5 map         | Object |
  | baseline             | container   |TBA49 | 5 map         | Object |
  | current-config       | container   |TBA50 | 5 map         | Object |
  | max-config-values    | container   |TBA51 | 5 map         | Object |
  | min-config-values    | container   |TBA52 | 5 map         | Object |
  | supported-units      | container   |TBA53 | 5 map         | Object |
  | server-originated-   | boolean     |TBA54 | 7 bits 20     | False  |
  |          telemetry   |             |      | 7 bits 21     | True   |
  | telemetry-notify-    | uint32      |TBA55 | 0 unsigned    | Number |
  |           interval   |             |      |               |        |
  | tmid                 | uint32      |TBA56 | 0 unsigned    | Number |
  | measurement-interval | enumeration |TBA57 | 0 unsigned    | String |
  | measurement-sample   | enumeration |TBA58 | 0 unsigned    | String |
  | talker               | list        |TBA59 | 4 array       | Array  |
  | source-prefix        | inet:       |TBA60 | 3 text string | String |
  |                      |   ip-prefix |      |               |        |
  | mid-list             | leaf-list   |TBA61 | 4 array       | Array  |
  |                      | uint32      |      | 0 unsigned    | Number |
  | source-port-range    | list        |TBA62 | 4 array       | Array  |
  | source-icmp-type-    | list        |TBA63 | 4 array       | Array  |
  |    range             |             |      |               |        |
  | lower-type           | uint8       |TBA64 | 0 unsigned    | Number |

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  | upper-type           | uint8       |TBA65 | 0 unsigned    | Number |
  | target               | container   |TBA66 | 5 map         | Object |
  | capacity             | uint64      |TBA67 | 0 unsigned    | String |
  | protocol             | uint8       |TBA68 | 0 unsigned    | Number |
  | total-traffic-       |             |      |               |        |
  |  normal-per-protocol | list        |TBA69 | 4 array       | Array  |
  | total-traffic-       |             |      |               |        |
  |  normal-per-port     | list        |TBA70 | 4 array       | Array  |
  | total-connection-    |             |      |               |        |
  |  capacity-per-port   | list        |TBA71 | 4 array       | Array  |
  | total-traffic-       |             |      |               |        |
  |  -protocol           | list        |TBA72 | 4 array       | Array  |
  | total-traffic- port  | list        |TBA73 | 4 array       | Array  |
  | total-attack-        |             |      |               |        |
  |  traffic-protocol    | list        |TBA74 | 4 array       | Array  |
  | total-attack-        |             |      |               |        |
  |  traffic-port        | list        |TBA75 | 4 array       | Array  |
  | total-attack-        |             |      |               |        |
  |  connection-port     | list        |TBA76 | 4 array       | Array  |
  | port                 | inet:       |      |               |        |
  |                      |  port-number|TBA77 | 0 unsigned    | Number |
  | query-type           | leaf-list   |TBA78 | 4 array       | Array  |
  |                      |             |      | 0 unsigned    | String |
  | vendor-id            | uint32      |TBA79 | 0 unsigned    | Number |
  | ietf-dots-telemetry: |             |      |               |        |
  |      telemetry-setup | container   |TBA80 | 5 map         | Object |
  | ietf-dots-telemetry: |             |      |               |        |
  |   total-traffic      | list        |TBA81 | 4 array       | Array  |
  | ietf-dots-telemetry: |             |      |               |        |
  | total-attack-traffic | list        |TBA82 | 4 array       | Array  |
  | ietf-dots-telemetry: |             |      |               |        |
  |    total-attack-     |             |      |               |        |
  |        connection    | container   |TBA83 | 5 map         | Object |
  | ietf-dots-telemetry: |             |      |               |        |
  |    attack-detail     | list        |TBA84 | 4 array       | Array  |
  +----------------------+-------------+------+---------------+--------+

12.  IANA Considerations

12.1.  DOTS Signal Channel CBOR Key Values

   This specification registers the DOTS telemetry attributes in the
   IANA "DOTS Signal Channel CBOR Key Values" registry [Key-Map].

   The DOTS telemetry attributes defined in this specification are
   comprehension-optional parameters.

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   o  Note to the RFC Editor: CBOR keys are assigned from the 128-255
      range.

   +----------------------+-------+-------+------------+---------------+
   | Parameter Name       | CBOR  | CBOR  | Change     | Specification |
   |                      | Key   | Major | Controller | Document(s)   |
   |                      | Value | Type  |            |               |
   +======================+=======+=======+============+===============+
   | tsid                 | TBA1  |   0   |    IESG    |   [RFCXXXX]   |
   | telemetry            | TBA2  |   5   |    IESG    |   [RFCXXXX]   |
   | low-percentile       | TBA3  | 6tag4 |    IESG    |   [RFCXXXX]   |
   | mid-percentile       | TBA4  | 6tag4 |    IESG    |   [RFCXXXX]   |
   | high-percentile      | TBA5  | 6tag4 |    IESG    |   [RFCXXXX]   |
   | unit-config          | TBA6  |   4   |    IESG    |   [RFCXXXX]   |
   | unit                 | TBA7  |   0   |    IESG    |   [RFCXXXX]   |
   | unit-status          | TBA8  |   7   |    IESG    |   [RFCXXXX]   |
   | total-pipe-capability| TBA9  |   4   |    IESG    |   [RFCXXXX]   |
   | link-id              | TBA10 |   3   |    IESG    |   [RFCXXXX]   |
   | pre-or-ongoing-      | TBA11 |   4   |    IESG    |   [RFCXXXX]   |
   |         mitigation   |       |       |            |               |
   | total-traffic-normal | TBA12 |   4   |    IESG    |   [RFCXXXX]   |
   | low-percentile-g     | TBA13 |   0   |    IESG    |   [RFCXXXX]   |
   | mid-percentile-g     | TBA14 |   0   |    IESG    |   [RFCXXXX]   |
   | high-percentile-g    | TBA15 |   0   |    IESG    |   [RFCXXXX]   |
   | peak-g               | TBA16 |   0   |    IESG    |   [RFCXXXX]   |
   | total-attack-traffic | TBA17 |   4   |    IESG    |   [RFCXXXX]   |
   | total-traffic        | TBA18 |   4   |    IESG    |   [RFCXXXX]   |
   | total-connection-    | TBA19 |   4   |    IESG    |   [RFCXXXX]   |
   |        capacity      |       |       |            |               |
   | connection           | TBA20 |   0   |    IESG    |   [RFCXXXX]   |
   | connection-client    | TBA21 |   0   |    IESG    |   [RFCXXXX]   |
   | embryonic            | TBA22 |   0   |    IESG    |   [RFCXXXX]   |
   | embryonic-client     | TBA23 |   0   |    IESG    |   [RFCXXXX]   |
   | connection-ps        | TBA24 |   0   |    IESG    |   [RFCXXXX]   |
   | connection-client-ps | TBA25 |   0   |    IESG    |   [RFCXXXX]   |
   | request-ps           | TBA26 |   0   |    IESG    |   [RFCXXXX]   |
   | request-client-ps    | TBA27 |   0   |    IESG    |   [RFCXXXX]   |
   | partial-request-ps   | TBA28 |   0   |    IESG    |   [RFCXXXX]   |
   | partial-request-     | TBA29 |   0   |    IESG    |   [RFCXXXX]   |
   |        client-ps     |       |       |            |               |
   | total-attack-        | TBA30 |   5   |    IESG    |   [RFCXXXX]   |
   |        connection    |       |       |            |               |
   | low-percentile-l     | TBA31 |   4   |    IESG    |   [RFCXXXX]   |
   | mid-percentile-l     | TBA32 |   4   |    IESG    |   [RFCXXXX]   |
   | high-percentile-l    | TBA33 |   4   |    IESG    |   [RFCXXXX]   |
   | peak-l               | TBA34 |   4   |    IESG    |   [RFCXXXX]   |
   | attack-detail        | TBA35 |   4   |    IESG    |   [RFCXXXX]   |
   | id                   | TBA36 |   0   |    IESG    |   [RFCXXXX]   |

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   | attack-id            | TBA37 |   0   |    IESG    |   [RFCXXXX]   |
   | attack-description   | TBA38 |   3   |    IESG    |   [RFCXXXX]   |
   | attack-severity      | TBA39 |   0   |    IESG    |   [RFCXXXX]   |
   | start-time           | TBA40 |   0   |    IESG    |   [RFCXXXX]   |
   | end-time             | TBA41 |   0   |    IESG    |   [RFCXXXX]   |
   | source-count         | TBA42 |   5   |    IESG    |   [RFCXXXX]   |
   | top-talker           | TBA43 |   5   |    IESG    |   [RFCXXXX]   |
   | spoofed-status       | TBA44 |   7   |    IESG    |   [RFCXXXX]   |
   | low-percentile-c     | TBA45 |   5   |    IESG    |   [RFCXXXX]   |
   | mid-percentile-c     | TBA46 |   5   |    IESG    |   [RFCXXXX]   |
   | high-percentile-c    | TBA47 |   5   |    IESG    |   [RFCXXXX]   |
   | peak-c               | TBA48 |   5   |    IESG    |   [RFCXXXX]   |
   | ietf-dots-signal-cha | TBA49 |   5   |    IESG    |   [RFCXXXX]   |
   | current-config       | TBA50 |   5   |    IESG    |   [RFCXXXX]   |
   | max-config-value     | TBA51 |   5   |    IESG    |   [RFCXXXX]   |
   | min-config-values    | TBA52 |   5   |    IESG    |   [RFCXXXX]   |
   | supported-units      | TBA55 |   5   |    IESG    |   [RFCXXXX]   |
   | server-originated-   | TBA54 |   7   |    IESG    |   [RFCXXXX]   |
   |          telemetry   |       |       |            |               |
   | telemetry-notify-    | TBA55 |   0   |    IESG    |   [RFCXXXX]   |
   |           interval   |       |       |            |               |
   | tmid                 | TBA56 |   0   |    IESG    |   [RFCXXXX]   |
   | measurement-interval | TBA57 |   0   |    IESG    |   [RFCXXXX]   |
   | measurement-sample   | TBA58 |   0   |    IESG    |   [RFCXXXX]   |
   | talker               | TBA59 |   0   |    IESG    |   [RFCXXXX]   |
   | source-prefix        | TBA60 |   0   |    IESG    |   [RFCXXXX]   |
   | mid-list             | TBA61 |   4   |    IESG    |   [RFCXXXX]   |
   | source-port-range    | TBA62 |   4   |    IESG    |   [RFCXXXX]   |
   | source-icmp-type-    | TBA63 |   4   |    IESG    |   [RFCXXXX]   |
   |           range      |       |       |            |               |
   | lower-type           | TBA64 |   0   |    IESG    |   [RFCXXXX]   |
   | upper-type           | TBA65 |   0   |    IESG    |   [RFCXXXX]   |
   | target               | TBA66 |   5   |    IESG    |   [RFCXXXX]   |
   | capacity             | TBA67 |   0   |    IESG    |   [RFCXXXX]   |
   | protocol             | TBA68 |   0   |    IESG    |   [RFCXXXX]   |
   | total-traffic-       | TBA69 |   4   |    IESG    |   [RFCXXXX]   |
   |  normal-per-protocol |       |       |            |               |
   | total-traffic-       | TBA70 |   4   |    IESG    |   [RFCXXXX]   |
   |  normal-per-port     |       |       |            |               |
   | total-connection-    | TBA71 |   4   |    IESG    |   [RFCXXXX]   |
   |  capacity-per-port   |       |       |            |               |
   | total-traffic-       | TBA72 |   4   |    IESG    |   [RFCXXXX]   |
   |  -protocol           |       |       |            |               |
   | total-traffic-port   | TBA73 |   4   |    IESG    |   [RFCXXXX]   |
   | total-attack-        | TBA74 |   4   |    IESG    |   [RFCXXXX]   |
   |  traffic-protocol    |       |       |            |               |
   | total-attack-        | TBA75 |   4   |    IESG    |   [RFCXXXX]   |
   |  traffic-port        |       |       |            |               |

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   | total-attack-        | TBA76 |   4   |    IESG    |   [RFCXXXX]   |
   |  connection-port     |       |       |            |               |
   | port                 | TBA77 |   0   |    IESG    |   [RFCXXXX]   |
   | query-type           | TBA78 |   4   |    IESG    |   [RFCXXXX]   |
   | vendor-id            | TBA79 |   0   |    IESG    |   [RFCXXXX]   |
   | ietf-dots-telemetry: | TBA80 |   5   |    IESG    |   [RFCXXXX]   |
   |   telemetry-setup    |       |       |            |               |
   | ietf-dots-telemetry: | TBA81 |   0   |    IESG    |   [RFCXXXX]   |
   |   total-traffic      |       |       |            |               |
   | ietf-dots-telemetry: | TBA82 |   0   |    IESG    |   [RFCXXXX]   |
   | total-attack-traffic |       |       |            |               |
   | ietf-dots-telemetry: | TBA83 |   0   |    IESG    |   [RFCXXXX]   |
   | total-attack-        |       |       |            |               |
   |        connection    |       |       |            |               |
   | ietf-dots-telemetry: | TBA84 |   4   |    IESG    |   [RFCXXXX]   |
   |     attack-detail    |       |       |            |               |
   +----------------------+-------+-------+------------+---------------+

12.2.  DOTS Signal Channel Conflict Cause Codes

   This specification requests IANA to assign a new code from the "DOTS
   Signal Channel Conflict Cause Codes" registry [Cause].

    +------+-------------------+------------------------+-------------+
    | Code | Label             |   Description          |  Reference  |
    +======+===================+========================+=============+
    | TBA  | overlapping-pipes | Overlapping pipe scope |  [RFCXXXX]  |
    +------+-------------------+------------------------+-------------+

12.3.  DOTS Signal Telemetry YANG Module

   This document requests IANA to register the following URIs in the
   "ns" subregistry within the "IETF XML Registry" [RFC3688]:

            URI: urn:ietf:params:xml:ns:yang:ietf-dots-telemetry
            Registrant Contact: The IESG.
            XML: N/A; the requested URI is an XML namespace.

            URI: urn:ietf:params:xml:ns:yang:ietf-dots-mapping
            Registrant Contact: The IESG.
            XML: N/A; the requested URI is an XML namespace.

   This document requests IANA to register the following YANG modules in
   the "YANG Module Names" subregistry [RFC6020] within the "YANG
   Parameters" registry.

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            name: ietf-dots-telemetry
            namespace: urn:ietf:params:xml:ns:yang:ietf-dots-telemetry
            maintained by IANA: N
            prefix: dots-telemetry
            reference: RFC XXXX

            name: ietf-dots-mapping
            namespace: urn:ietf:params:xml:ns:yang:ietf-dots-mapping
            maintained by IANA: N
            prefix: dots-mapping
            reference: RFC XXXX

13.  Security Considerations

13.1.  DOTS Signal Channel Telemetry

   The security considerations for the DOTS signal channel protocol are
   discussed in Section 12 of [I-D.boucadair-dots-rfc8782-bis].  The
   following discusses the security considerations that are specific to
   the DOTS signal channel extension defined in this document.

   The DOTS telemetry information includes DOTS client network topology,
   DOTS client domain pipe capacity, normal traffic baseline and
   connections capacity, and threat and mitigation information.  Such
   information is sensitive; it MUST be protected at rest by the DOTS
   server domain to prevent data leakage.

   DOTS clients are typically trusted devices by the DOTS client domain.
   DOTS clients may be co-located on network security services (e.g.,
   firewall) and a compromised security service potentially can do a lot
   more damage to the network.  This assumption differs from the often
   held view that devices are untrusted, often referred to as the "zero-
   trust model".  A compromised DOTS client can send fake DOTS telemetry
   data to a DOTS server to mislead the DOTS server.  This attack can be
   prevented by monitoring and auditing DOTS clients to detect
   misbehavior and to deter misuse, and by only authorizing the DOTS
   client to convey the DOTS telemetry for specific target resources
   (e.g., an application server is authorized to exchange DOTS telemetry
   for its IP addresses but a DDoS mitigator can exchange DOTS telemetry
   for any target resource in the network).  As a reminder, this is
   variation of dealing with compromised DOTS clients as discussed in
   Section 12 of [I-D.boucadair-dots-rfc8782-bis].

   DOTS servers must be capable of defending themselves against DoS
   attacks from compromised DOTS clients.  The following non-
   comprehensive list of mitigation techniques can be used by a DOTS
   server to handle misbehaving DOTS clients:

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   o  The probing rate (defined in Section 5.5 of
      [I-D.boucadair-dots-rfc8782-bis]) can be used to limit the average
      data rate to the DOTS server.

   o  Rate-limiting DOTS telemetry, including those with new 'tmid'
      values, from the same DOTS client defends against DoS attacks that
      would result in varying the 'tmid' to exhaust DOTS server
      resources.  Likewise, the DOTS server can enforce a quota and
      time-limit on the number of active pre-or-ongoing-mitigation
      telemetry data (identified by 'tmid') from the DOTS client.

   Note also that telemetry notification interval may be used to rate-
   limit the pre-or-ongoing-mitigation telemetry notifications received
   by a DOTS client domain.

13.2.  Vendor Attack Mapping

   The security considerations for the DOTS data channel protocol are
   discussed in Section 10 of [RFC8783].  The following discusses the
   security considerations that are specific to the DOTS data channel
   extension defined in this document.

   All data nodes defined in the YANG module specified in Section 10.2
   which can be created, modified, and deleted (i.e., config true, which
   is the default) are considered sensitive.  Write operations to these
   data nodes without proper protection can have a negative effect on
   network operations.  Appropriate security measures are recommended to
   prevent illegitimate users from invoking DOTS data channel primitives
   as discussed in [RFC8783].  Nevertheless, an attacker who can access
   a DOTS client is technically capable of undertaking various attacks,
   such as:

   o  Communicating invalid attack mapping details to the server
      ('/ietf-data:dots-data/ietf-data:dots-client/dots-
      telemetry:vendor-mapping'), which will mislead the server when
      correlating attack details.

   Some of the readable data nodes in the YANG module specified in
   Section 10.2 may be considered sensitive.  It is thus important to
   control read access to these data nodes.  These are the data nodes
   and their sensitivity:

   o  '/ietf-data:dots-data/ietf-data:dots-client/dots-telemetry:vendor-
      mapping' can be misused to infer the DDoS protection technology
      deployed in a DOTS client domain.

   o  '/ietf-data:dots-data/dots-telemetry:vendor-mapping' can be used
      by a compromised DOTS client to leak the attack detection

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      capabilities of the DOTS server.  This is a variation of the
      compromised DOTS client attacks discussed in Section 13.1.

14.  Contributors

   The following individuals have contributed to this document:

   o  Li Su, CMCC, Email: suli@chinamobile.com

   o  Pan Wei, Huawei, Email: william.panwei@huawei.com

15.  Acknowledgements

   The authors would like to thank Flemming Andreasen, Liang Xia, and
   Kaname Nishizuka co-authors of [I-D.doron-dots-telemetry] and
   everyone who had contributed to that document.

   The authors would like to thank Kaname Nishizuka, Wei Pan, and Yuuhei
   Hayashi for comments and review.

   Special thanks to Jon Shallow and Kaname Nishizuka for their
   implementation and interoperability work.

   Many thanks to Jan Lindblad for the yangdoctors review and Nagendra
   Nainar for the opsdir review.

16.  References

16.1.  Normative References

   [Enterprise-Numbers]
              "Private Enterprise Numbers", May 2020,
              <http://www.iana.org/assignments/enterprise-numbers.html>.

   [I-D.boucadair-dots-rfc8782-bis]
              Boucadair, M., Ed., Shallow, J., and T. Reddy.K,
              "Distributed Denial-of-Service Open Threat Signaling
              (DOTS) Signal Channel Specification",
              <https://tools.ietf.org/html/draft-boucadair-dots-rfc8782-
              bis-00>.

   [I-D.ietf-dots-signal-filter-control]
              Nishizuka, K., Boucadair, M., Reddy.K, T., and T. Nagata,
              "Controlling Filtering Rules Using Distributed Denial-of-
              Service Open Threat Signaling (DOTS) Signal Channel",
              draft-ietf-dots-signal-filter-control-07 (work in
              progress), June 2020.

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   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7049]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
              October 2013, <https://www.rfc-editor.org/info/rfc7049>.

   [RFC7252]  Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
              Application Protocol (CoAP)", RFC 7252,
              DOI 10.17487/RFC7252, June 2014,
              <https://www.rfc-editor.org/info/rfc7252>.

   [RFC7641]  Hartke, K., "Observing Resources in the Constrained
              Application Protocol (CoAP)", RFC 7641,
              DOI 10.17487/RFC7641, September 2015,
              <https://www.rfc-editor.org/info/rfc7641>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC7959]  Bormann, C. and Z. Shelby, Ed., "Block-Wise Transfers in
              the Constrained Application Protocol (CoAP)", RFC 7959,
              DOI 10.17487/RFC7959, August 2016,
              <https://www.rfc-editor.org/info/rfc7959>.

   [RFC7970]  Danyliw, R., "The Incident Object Description Exchange
              Format Version 2", RFC 7970, DOI 10.17487/RFC7970,
              November 2016, <https://www.rfc-editor.org/info/rfc7970>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8345]  Clemm, A., Medved, J., Varga, R., Bahadur, N.,
              Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
              Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
              2018, <https://www.rfc-editor.org/info/rfc8345>.

   [RFC8768]  Boucadair, M., Reddy.K, T., and J. Shallow, "Constrained
              Application Protocol (CoAP) Hop-Limit Option", RFC 8768,
              DOI 10.17487/RFC8768, March 2020,
              <https://www.rfc-editor.org/info/rfc8768>.

   [RFC8783]  Boucadair, M., Ed. and T. Reddy.K, Ed., "Distributed
              Denial-of-Service Open Threat Signaling (DOTS) Data
              Channel Specification", RFC 8783, DOI 10.17487/RFC8783,
              May 2020, <https://www.rfc-editor.org/info/rfc8783>.

   [RFC8791]  Bierman, A., Bjoerklund, M., and K. Watsen, "YANG Data
              Structure Extensions", RFC 8791, DOI 10.17487/RFC8791,
              June 2020, <https://www.rfc-editor.org/info/rfc8791>.

16.2.  Informative References

   [Cause]    IANA, "DOTS Signal Channel Conflict Cause Codes",
              <https://www.iana.org/assignments/dots/dots.xhtml#dots-
              signal-channel-conflict-cause-codes>.

   [I-D.bosh-core-new-block]
              Boucadair, M. and J. Shallow, "Constrained Application
              Protocol (CoAP) Block-Wise Transfer Options for Faster
              Transmission", draft-bosh-core-new-block-04 (work in
              progress), June 2020.

   [I-D.doron-dots-telemetry]
              Doron, E., Reddy, T., Andreasen, F., Xia, L., and K.
              Nishizuka, "Distributed Denial-of-Service Open Threat
              Signaling (DOTS) Telemetry Specifications", draft-doron-
              dots-telemetry-00 (work in progress), October 2016.

   [I-D.ietf-dots-multihoming]
              Boucadair, M., Reddy.K, T., and W. Pan, "Multi-homing
              Deployment Considerations for Distributed-Denial-of-
              Service Open Threat Signaling (DOTS)", draft-ietf-dots-
              multihoming-04 (work in progress), May 2020.

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   [I-D.ietf-dots-use-cases]
              Dobbins, R., Migault, D., Moskowitz, R., Teague, N., Xia,
              L., and K. Nishizuka, "Use cases for DDoS Open Threat
              Signaling", draft-ietf-dots-use-cases-25 (work in
              progress), July 2020.

   [Key-Map]  IANA, "DOTS Signal Channel CBOR Key Values",
              <https://www.iana.org/assignments/dots/dots.xhtml#dots-
              signal-channel-cbor-key-values>.

   [RFC2330]  Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
              "Framework for IP Performance Metrics", RFC 2330,
              DOI 10.17487/RFC2330, May 1998,
              <https://www.rfc-editor.org/info/rfc2330>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC8612]  Mortensen, A., Reddy, T., and R. Moskowitz, "DDoS Open
              Threat Signaling (DOTS) Requirements", RFC 8612,
              DOI 10.17487/RFC8612, May 2019,
              <https://www.rfc-editor.org/info/rfc8612>.

Authors' Addresses

   Mohamed Boucadair (editor)
   Orange
   Rennes  35000
   France

   Email: mohamed.boucadair@orange.com

   Tirumaleswar Reddy (editor)
   McAfee, Inc.
   Embassy Golf Link Business Park
   Bangalore, Karnataka  560071
   India

   Email: kondtir@gmail.com

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   Ehud Doron
   Radware Ltd.
   Raoul Wallenberg Street
   Tel-Aviv  69710
   Israel

   Email: ehudd@radware.com

   Meiling Chen
   CMCC
   32, Xuanwumen West
   BeiJing, BeiJing  100053
   China

   Email: chenmeiling@chinamobile.com

   Jon Shallow
   United Kingdom

   Email: supjps-ietf@jpshallow.com

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