Network Working Group                                 Luyuan Fang
   Internet Draft                                          Dan Frost
   Intended status: Informational                      Cisco Systems
   Expires: September 14, 2011                           Nabil Bitar
                                                             Verizon
                                                       Raymond Zhang
                                                                  BT
                                                            Lei Wang
                                                             Telenor
                                                         Kam Lee Yap
                                                   XO Communications
                                                     Michael Fargano
                                                               Qwest
                                                          John Drake
                                                             Juniper
                                                       Thomas Nadeau


                                                      March 14, 2011


                            MPLS-TP OAM Toolset
                   draft-fang-mpls-tp-oam-toolset-01.txt

Abstract


   This document provides an overview of the MPLS-TP OAM toolset,
   which consists of MPLS-TP fault management and performance
   monitoring. This overview includes a brief recap of MPLS-TP OAM
   requirements and functions, and of the generic mechanisms created
   in the MPLS data plane to support in-band OAM. The importance of
   using IANA assigned code point under G-Ach when supporting MPLS-TP
   OAM is also discussed. The protocol definitions for each individual
   MPLS-TP OAM tool are specified in separate RFCs or Working Group
   documents which are referenced by this document.


Status of this Memo

   This Internet-Draft is submitted to IETF 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 http://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

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   MPLS-TP OAM-Toolset                                    March 2011

   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 September 14, 2011.


Copyright Notice


   Copyright (c) 2011 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
   (http://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 ...................................................3
   3. Brief Overview of MPLS-TP OAM Requirements ....................6
   3.1.  Architectural Requirements .................................6
   3.2.  Functional Requirements ....................................6
   4. MPLS-TP OAM Mechanisms and Toolset Summary ....................7
   4.1.  In-band OAM Mechanisms .....................................8
   4.2.  Fault Management Toolset ...................................8
   4.3.  Performance Monitoring Toolset ............................10
   5. OAM Toolset Utilization and Protocol Definitions .............10
   5.1.  Connectivity Check and Connectivity Verification ..........10
   5.2   Diagnostic Tests and Lock Instruct. .......................11
   5.3.  Lock Reporting ............................................11
   5.4.  Alarm Reporting and Link down Indication ..................12
   5.5.  Remote Defect Indication ..................................12
   5.6.  Packet Loss and Delay Measurement .........................13
   6. IANA assigned code points under G-Ach ........................14
   7. Security Considerations ......................................15
   8. IANA Considerations ..........................................15


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   9. Normative References .........................................15
   10.  Informative References .....................................16
   11.  Authors' Addresses..........................................17



Requirements Language

   Although this document is not a protocol specification, the key
   words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in
   this document are to be interpreted as described in RFC 2119 [RFC
   2119].


1. Introduction

   The Operations, Administration, and Maintenance (OAM) Requirements
   for Transport Profile of Multiprotocol Label Switching (MPLS-TP)
   networks are defined in RFC 5860 [RFC 5860]. MPLS-TP OAM mechanisms
   and multiple OAM tools have been developed based on MPLS-TP OAM
   requirements.

   This document provides an overview of the MPLS-TP OAM toolset,
   which consists of MPLS-TP fault management and performance
   monitoring. This overview includes a brief recap of MPLS-TP OAM
   requirements and functions, and of the generic mechanisms created
   in the MPLS data plane to support in-band OAM. The importance of
   using IANA assigned code point under G-Ach when supporting MPLS-TP
   OAM is also discussed.

   The protocol definitions for each individual MPLS-TP OAM tool are
   specified in separate RFCs or Working Group documents while this
   document is work in progress, which are referenced by this
   document.

   The protocol definitions for each individual MPLS-TP OAM tool are
   defined in separate RFCs (or Working Group documents while this
   document is work in progress) referenced by this document.

2.  Terminology

   This document uses  MPLS-TP OAM specific terminology.

        Term    Definition
      ----------------------------------------------------
        AC      Attachment Circuit

        AIS     Alarm indication signal

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   MPLS-TP OAM-Toolset                                    March 2011


        APS     Automatic Protection Switching

        ATM     Asynchronous Transfer Mode

        BFD     Bidirectional Forwarding Detection

        CC      Continuity Check

        CE      Customer-Edge device

        CM      Configuration Management

        CoS     Class of Service

        CV      Connectivity Verification

        FM      Fault Management

        GAL     Generic Alert Label

        G-ACH   Generic Associated Channel

        GMPLS   Generalized Multi-Protocol Label Switching

        LDI     Link Down Indication

        LDP     Label Distribution Protocol

        LER     Label Edge Router

        LKR     Lock Report

        LM      Loss Measurement

        LMEG    LSP ME Group

        LOC     Loss of Continuity

        LSP     Label Switched Path

        LSR     Label Switching Router

        LSME    LSP SPME ME

        LSMEG   LSP SPME ME Group

        ME      Maintenance Entity


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   MPLS-TP OAM-Toolset                                    March 2011

        MEG     Maintenance Entity Group

        MEP     Maintenance Entity Group End Point

        MIP     Maintenance Entity Group Intermediate Point

        MPLS    MultiProtocol Label Switching

        NMS     Network Management System

        NTP     Network Time Protocol

        OAM     Operations, Administration, and Management

        PE      Provider Edge

        PM      Performance Monitoring

        PME     PW Maintenance Entity

        PMEG    PW ME Group

        PSME    PW SPME ME

        PSMEG   PW SPME ME Group

        PW      Pseudowire

        QoS     Quality of Service

        RDI     Remote Defect Indication

        SDH     Synchronous Digital Hierarchy

        SLA     Service Level Agreement

        SME     Section Maintenance Entity

        SMEG    Section ME Group

        SONET   Synchronous Optical Network

        SPME    Sub-path Maintenance Element

        S-PE    Switching Provider Edge

        SRLG    Shared Risk Link Group

        TC      Traffic Class

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   MPLS-TP OAM-Toolset                                    March 2011


        T-PE    Terminating Provider Edge


3. Brief Overview of MPLS-TP OAM Requirements

   This following Architectural and Functional Requirements are
   defined by RFC 5860. They are captured here for easy reading before
   discussing the toolset.

   3.1.  Architectural Requirements

   The MPLS-TP OAM Supports point-to-point bidirectional PWs, point-
   to-point co-routed bidirectional LSPs, point-to-point bidirectional
   Sections, point-to-point associated bidirectional LSPs, point-to-
   point unidirectional LSPs, and point-to-multipoint LSPs. In
   addition, MPLS-TP OAM supports these LSPs and PWs when they span
   single domain or multiple domains.

   The protocol solution(s) SHOULD be independent of the underlying
   tunneling or point-to-point technology or transmission media. The
   protocol solution(s) SHOULD be independent of the service a PW may
   emulate.

   In-band OAM MUST be implemented. OAM packets for a specific PW,
   LSP, or Section MUST follow the exact same data path as user
   traffic of the same.

   The solutions MUST support OAM functions with or without relying on
   IP capabilities.

   It is REQUIRED that OAM interoperability be achieved between
   distinct domains with different operational models, e.g. with IP or
   without IP support in the data plane.

   And OAM functions MUST be configurable even in the absence of a
   control plane.

   3.2. Functional Requirements

   In general, MPLS-TP OAM tools MUST provide functions to detect,
   diagnose, localize, and notify the faults when occur. The mechanism
   for correction actions trigged by fault detection SHOULD be
   provided.

   The following are the fault detection functional requirements

   - Continuity Checks: a function to enable an End Point to monitor
   the liveness of a PW, LSP, or Section.

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   MPLS-TP OAM-Toolset                                    March 2011


   - Connectivity Verifications: a function to enable an End Point to
   determine whether or not it is connected to specific End Point(s)
   by means of the expected PW, LSP, or Section.

   - Route Tracing: the functionality to enable an End Point to
   discover the Intermediate (if any) and End Point(s) along a PW,
   LSP, or Section, and more generically to trace the route of a PW,
   LSP or Section.

   - Diagnostic Tests: a function to enable conducting diagnostic
   tests on a PW, LSP, or Section.  For example, a loop-back function.

   - Lock Instruct: the functionality to enable an End Point of a PW,
   LSP, or Section to instruct its associated End Point(s) to lock the
   PW, LSP, or Section.

   - Lock Reporting: a function to enable an Intermediate Point of a
   PW or LSP to report, to an End Point of that same PW or LSP, a lock
   condition indirectly affecting that PW or LSP.

   - Alarm Reporting: the functionality to enable an Intermediate
   Point of a PW or LSP to report, to an End Point of that same PW or
   LSP, a fault or defect condition indirectly affecting that PW or
   LSP.

   - Remote Defect Indication: a function to enable an End Point to
   report, to its associated End Point, a fault or defect condition
   that it detects on a PW, LSP, or Section for which they are the End
   Points.

   - Client Failure Indication: a function to enable the propagation,
   from edge to edge of an MPLS-TP network, of information pertaining
   to a client fault condition detected at an End Point of a PW or
   LSP, if the client layer OAM does not provide alarm notification.

   - Packet Loss Measurement: a function to enable the quantification
   of packet loss ratio over a PW, LSP, or Section.

   - Packet Delay Measurement: a function to enable the quantification
   of the one-way, and if appropriate, the two-way, delay ratio of a
   PW, LSP, or Section.


4. MPLS-TP OAM Mechanisms and Toolset Summary

   The following subsections provide the summary of MPLS-TP OAM Fault
   Management and Performance Management toolset, with indication of
   the corresponding IETF RFCs (or Internet drafts while this document

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   MPLS-TP OAM-Toolset                                    March 2011

   is work in progress) to support the MPLS-TP OAM functions defined
   in RFC 5860.


   4.1. In-band OAM Mechanisms

   To meet the In-band OAM requirements for MPLS-TP, Generic
   Associated Channel is created [RFC 5586]. It generalizes the
   applicability of the Pseudowire (PW) Associated Channel Header
   (ACH) to MPLS Label Switching Paths (LSPs), and Sections.

   The Generic Associated Label (GAL) [RFC 5586] is defined by
   assigning one of the reserved MPLS label values to the G-Ach, GAL
   identifies the presence of the Associated Channel Header following
   the label stack.

   The creation of G-Ach and GAL provided the necessary mechanisms for
   building in-band OAM MPLS-TP toolset.

   RFC 5718 [RFC 5718] An-In-Band Data Communication Network for the
   MPLS Transport Profile describes how the G-Ach may be used for
   Management and Signaling Communication.


   4.2. Fault Management Toolset

   The following tables provide the summary of MPLS-TP OAM toolset.

   Table 1 provides the summary of MPLS-TP OAM Fault Management
   toolset functions, associated tool/protocol, and the corresponding
   IETF RFCs or Internet drafts where they are defined.

   Table 2 provides the Performance Monitoring Functions, associated
   tool/protocol definitions, and the corresponding IETF RFCs or
   Internet Drafts where they are defined.

   The following table provide the Performance Monitoring Functions,
   protocol definitions, and corresponding RFCs or Internet Drafts.

   (Editor's note: only RFCs will be referenced in the final version
   of the document).









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   MPLS-TP OAM-Toolset                                    March 2011


   +----------------------------------------------------------------+
   |           Proactive Fault Management OAM Toolset               |
   |----------------------------------------------------------------|
   |OAM Functions     |OAM Tools/Protocols     | RFCs / IDs         |
   |------------------|------------------------|--------------------|
   |Continuity Check  |Bidirectional Forwarding| draft-ietf-mpls-tp |
   |(CV) & Continuity |Detection (BFD)         | -cc-cv-rdi [cc-cv] |
   |Verification(CV)  |                        |                    |
   |------------------|------------------------|--------------------|
   |Remote Defect     |Bidirectional Forwarding| draft-ietf-mpls-tp |
   |Indication (RDI)  |Detection (BFD)         | -cc-cv-rdi [cc-cv] |
   |------------------|------------------------|--------------------|
   |Alarm Indication  |AIS message under G-Ach | draft-ietf-mpls-tp |
   |Signal (AIS)      |                        | -fault [fault]     |
   |------------------|------------------------|--------------------|
   |Link Down         |Flag in AIS message     | draft-ietf-mpls-tp |
   |Indication (LDI)  |                        | -fault [fault]     |
   |------------------|------------------------|--------------------|
   |Lock Report (LKR) |LKR message under G-Ach | draft-ietf-mpls-tp |
   |                  |                        | -fault [fault]     |
   +----------------------------------------------------------------+

           Table 1. Proactive Fault Management OAM Toolset




   +----------------------------------------------------------------+
   |           On Demand Fault Management OAM Toolset               |
   |----------------------------------------------------------------|
   |OAM Functions     |OAM Tools/Protocols     | RFCs / IDs         |
   |------------------|------------------------|--------------------|
   |Continuity        |LSP Ping and BFD        | draft-ietf-mpls-tp |
   |Verification(CV)  |                        | -cc-cv-rdi [cc-cv] |
   |------------------|------------------------|--------------------|
   |Diagnostic:       |1) In-band Loopback     | draft-ietf-mpls-tp |
   |Loopback, Lock    | and Lock Instruct      | -li-lb [li-lb]     |
   |and LSP Ping      |2) LSP Ping             |                    |
   |------------------|------------------------|--------------------|
   |Lock Instruct     | In-band lock message   | draft-ietf-mpls-tp |
   |(LI)              | in G-Ach               | -li-lb [li-lb]     |
   +----------------------------------------------------------------+

           Table 2. On Demand Fault Management OAM Toolset





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   4.3. Performance Monitoring Toolset

   Table 3 provides the Performance Monitoring Fuctions, protocol
   definitions, and corresponding RFCs or Internet Drafts.
   +----------------------------------------------------------------+
   |           Performance Monitoring OAM Toolset                   |
   |----------------------------------------------------------------|
   |OAM Functions     |Protocols Definitions   | RFCs / IDs         |
   |------------------|------------------------|--------------------|
   |Packet loss       |LM & DM query messages  | draft-ietf-mpls-tp |
   |measurement (LM)  |                        | -loss-delay [lo-de]|
   |------------------|------------------------|                    |
   |Packet delay (DM) |LM & DM query messages  | draft-ietf-mpls-tp |
   |measurement       |                        | -loss-delay        |
   |------------------|------------------------|-profile [tp-lo-de] |
   |Throughput        |derived from Loss       |                    |
   |measurement       |measurement             |                    |
   |------------------|------------------------|                    |
   |Delay Variation   |Supported from Delay    |                    |
   |measurement       |measurement             |                    |
   +----------------------------------------------------------------+

           Table 3. Performance Monitoring OAM Toolset



5. OAM Toolset Utilization and Protocol Definitions

   5.1. Connectivity Check and Connectivity Verification

   Continuity Check (CC) and Proactive Connectivity Verification (CV)
   functions are used to detect loss of continuity (LOC), and
   unintended connectivity between two MEPs.

   Loss of connectivity, mis-merging, mis-connectivity, or unexpected
   Maintenance Entity Group End Points (MEPs) can be detected using
   the CC/CV tools.

   The CC/CV tools are used to support MPLS-TP fault management,
   performance management, and protection switching.

   Bidirectional Forwarding Detection (BFD) and LSP Ping are defined
   to support the CC/CV functions [cc-cv].

   BFD control packets are sent by the source MEP to sink MEP. The
   sink MEP monitors the arrival of the BFD control packets and
   detects the defect.

   The interval of BFD control packet can be configured. For example:

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   MPLS-TP OAM-Toolset                                    March 2011

        - 3.3ms is the default interval for protection switching.
        - 100ms is the default interval for performance monitoring.
        - 1s is the default interval for fault management.


   5.2. Diagnostic Tests and Lock Instruct

   The OAM functions to support diagnostic tests are required in the
   transport environment.

   The Loopback mode is defined for management purpose in [li-lb]. The
   mechanism is provided to Lock and unlock traffic (e.g. data and
   control traffic) or specific OAM traffic at a specific LSR on the
   path of the MPLS-TP LSP to allow loop back it to the source by [li-
   lb].

   These diagnostic functions apply to associated bidirectional MPLS-
   TP LSPs, including MPLS-TP LSPs, bi-directional RSVP-TE tunnels
   (which is relevant for MPLS-TP dynamic control plane option with
   GMPLS), and single segment and multi-segment pseudowires.

   The Lock operation instruction is carried in an MPLS Loopback
   request message sent from a MEP to a trail-end MEP of the LSP to
   request that the LSP be taken out of service.  In response, the
   Lock operation reply is carried in a Loopback response message sent
   from the trail-end MEP back to the originating MEP to report the
   result.

   The loopback operations include [li-lb]:
        - Lock: take an LSP out of service for maintenance.
        - Unlock: Restore a previously locked LSP to service.
        - Set_Full_Loopback and Set_OAM_Loopback
        - Unset_Full_Loopback and Set_OAM_Loopback

   Operators can use the loopback mode to test the connectivity or
   performance (loss, delay, delay variation, and throughput) of given
   LSP upto a specific node on the path of the LSP.


   5.3. Lock Reporting

   The Lock Report (LKR) function is used to communicate to the client
   (sub-) layer MEPs the administrative locking of a server (sub-)
   layer MEP, and consequential interruption of data traffic
   forwarding in the client (sub-) layer [fault].

   When operator is taking the LSP out of service for maintenance
   other operational reason, using the LKR function can help to


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   MPLS-TP OAM-Toolset                                    March 2011

   distinguish the condition as administrative locking from defect
   condition.

   The Lock Report function would also serve the purpose of alarm
   suppression in the MPLS-TP network above the level of the Lock is
   occurred. The receipt of an LKR message MAY be treated as the
   equivalent of loss of continuity at the client layer [fault].


   5.4. Alarm Reporting and Link down Indication


   Alarm Indication Signal (AIS) message serves the purpose of alarm
   suppression upon the failure detection in the server (-sub) layer.
   When the Link Down Indication (RDI) is set, the AIS message MAY be
   used to trigger recovery mechanisms [fault].

   When a server MEP detects the failure, it asserts Loss of
   Continuity (LOC) or signal fail which sets the flag up to generate
   OAM packet with AIS message. The AIS message is forwarded to
   downstream sink MEP in the client layer. This would enable the
   client layer to suppress the generation of secondary alarms.

   A Link Down Indication (LDI) flag is defined in the AIS message.
   The LDI flag is set in the AIS message in response to detecting a
   fatal failure in the server layer.  Receipt of an AIS message with
   this flag set MAY be interpreted by a MEP as an indication of
   signal fail at the client layer. [fault]

   Fault OAM messages are generated by intermediate nodes where an LSP
   is switched, and propagated to the end points (MEPs).

   From practical point of view, when both proactive CC functions and
   LDI are used, one may consider to run the proactive CC functions at
   a slower rate (e.g. longer BFD hello intervals), and reply on LDI
   to trigger fast protection switch over upon failure detection in a
   given LSP.


   5.5. Remote Defect Indication

   Remote Defect Indication (RDI) function enables an End Point to
   report to the other End Point that a fault or defect condition is
   detected on the PW, LSP, or Section they are the End Points.

   The RDI OAM function is supported by the use of Bidirectional
   Forwarding Detection (BFD) Control Packets [cc-cv]. RDI is only
   used for bidirectional connections and is associated with proactive
   CC/CV activation.

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   MPLS-TP OAM-Toolset                                    March 2011


   When an end point (MEP) detects a signal failure condition, it sets
   the flag up by setting the diagnostic field of the BFD control
   packet to a particular value to indicate the failure condition on
   the associated PW, LSP, or Section, and transmitting the BFD
   control packet with the failure flag up to the other end point (its
   peer MEP).

   RDI function can be used to facilitate the protection switching by
   synchronizing the two end points when unidirectional failure occurs
   and is detected by one end.


   5.6. Packet Loss and Delay Measurement

   Packet loss and delay measurement toolset enables operators to
   measure the quality of the packet transmission over a PW, LSP, or
   Section.

   The protocol for MPLS-TP loss and delay measurement functions is
   defined in [lo-de] as profiled in [tp-lo-de]. These documents
   specify how to measure Packet Loss, Packet Delay, Packet Delay
   Variation, and Throughput.

   The loss and delay protocols have the following characteristics and
   capabilities:

        - Support measurement of packet loss, delay and throughput
           over Label Switched Paths (LSPs), pseudowires, and MPLS
           sections (links).

        - The same LM and DM protocols can be used for both
           continuous/proactive and selective/on-demand measurement.

        - The LM and DM protocols use a simple query/response model
           for bidirectional measurement that allows a single node -
           the querier - to measure the loss or delay in both
           directions.

        - The LM and DM protocols use query messages for
           unidirectional loss and delay measurement.  The measurement
           can either be carried out at the downstream node(s) or at
           the querier if an out-of-band return path is available.

        - The LM and DM protocols do not require that the transmit and
           receive interfaces be the same when performing bidirectional
           measurement.



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   MPLS-TP OAM-Toolset                                    March 2011

        - The LM protocol supports both 32-bit and 64-bit counters
           although for simplicity only 32-bit packet counters are
           currently included in the MPLS-TP profile.

        - The LM protocol supports measurement in terms of both packet
           counts and octet counts although for simplicity only packet
           counters are currently included in the MPLS-TP profile.

        - The LM protocol can be used to measure channel throughput as
           well as packet loss.

        - The DM protocol supports varying the measurement message
           size in order to measure delays associated with different
           packet sizes.



6. IANA assigned code points under G-Ach

   OAM toolset/functions defined under G-Ach MUST use IANA assigned
   code points, using Experimental Code Point under G-Ach is
   inappropriate and it can lead to interoperability problems and
   potential Code Point collision in production network.

   RFC 5586 "MPLS Generic Associated Channel" stated the following in
   IANA consideration section: A requirement has emerged (see [RFC
   5860]) to allow for optimizations or extensions to OAM and other
   control protocols running in an associated channel to be
   experimented without resorting to the IETF standards process, by
   supporting experimental code points. This would prevent code points
   used for such functions from being used from the range allocated
   through the IETF standards and thus protects an installed base of
   equipment from potential inadvertent overloading of code points.
   In order to support this requirement, IANA has changed the code
   point allocation scheme for the PW Associated Channel as follows:

        0 - 32751: IETF Review
        32760 - 32767: Experimental

   Code points in the experimental range MUST be used according to the
   guidelines of RFC 3692 [RFC 3692].  Functions using experimental G-
   Ach code points MUST be disabled by default.

   The guidelines on the usage of experimental numbers are defined in
   IETF RFC 3692. As indicated by RFC 3692: The experimental numbers
   are useful when experimenting new protocols or extending existing
   protocols in order to test and experiment with the new functions, as
   part of implementation.  RFC 3692 reserves a range of numbers for


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   MPLS-TP OAM-Toolset                                    March 2011

   experimentation when the need of such experimentation has been
   identified.

   However, the experimental numbers "are reserved for generic testing
   purposes, and other implementations may use the same numbers for
   different experimental uses." "Experimental numbers are intended for
   experimentation and testing and are not intended for wide or general
   deployments." "Shipping a product with a specific value pre-enabled
   would be inappropriate and can lead to interoperability problems
   when the chosen value collides with a different usage, as it someday
   surely will."

   Further more, "it would be inappropriate for a group of vendors, a
   consortia, or another Standards Development Organization to agree
   among themselves to use a particular value for a specific purpose
   and then agree to deploy devices using those values."  Experimental
   numbers are not guaranteed to be unique by definition. There is the
   risk of code point collision when using Experimental Code Point in
   production networks.

   Similar statements can also be found in RFC4929 "Change Process for
   Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS)
   Protocols and Procedures". As described in [RFC 4775], "non-
   standard extensions, including experimental values, are not to be
   portrayed as industrial standards whether by an individual vendor,
   an industry forum, or a standards body."



7. Security Considerations


   The document provides overview of MPLS-TP OAM requirements,
   functions, protocol, and solution considerations. The actual
   protocols for the OAM toolset are defined in separate documents and
   referenced by this document.

   The general security considerations are provided in Security
   Framework for MPLS and GMPLS Networks [RFC 5920], and MPLS-TP
   Security Framework [tp-sec-fr].


8. IANA Considerations

   This document contains no new IANA considerations.


9. Normative References


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   MPLS-TP OAM-Toolset                                    March 2011

   [RFC 5586], M. Bocci, M. Vigoureux, S. Bryant, "MPLS Generic
   Associated Channel",RFC 5586, June 2009.

   [RFC 5654], Niven-Jenkins, B., et al, "MPLS-TP Requirements", RFC
   5654, September 2009.

   [RFC 5718], D. Beller, and A. Farrel, "An In-Band Data
   Communication Network For the MPLS Transport Profile",  RFC 5718,
   Jan 2010.

   [RFC 5860], M. Vigoureux, D. Ward, M. Betts, "Requirements for
   Operations, Administration, and Maintenance (OAM) in MPLS Transport
   Networks", RFC 5860, May 2010.

   [cc-cv] D. Allan, G. Swallow, J. Drake, Proactive Connectivity
   Verification, Continuity Check and Remote Defect indication for
   MPLS Transport Profile, draft-ietf-mpls-tp-cc-cv-rdi-03, Feb. 2011.

   [fault] G. Swallow, A. Fulignoli, M. Vigoureux, MPLS Fault
   Management OAM, draft-ietf-mpls-tp-fault-01, March 2011.

   [li-lb] S. Boutros, S. Sivabalan, et,al., MPLS Transport Profile
   Lock Instruct and Loopback Functions draft-ietf-mpls-tp-li-lb-
   01.txt, March 2011.

   [loopback] S. Boutros, S. Sivabalan, G. Swallow, R. Aggarwal, M.
   Vigoureux,  Operating MPLS Transport Profile LSP in Loopback Mode,
   draft-boutros-mpls-tp-loopback-03.txt, March 2011.

   [lo-de] D. Frost, S. Bryant, Packet Loss and Delay Measurement for
   the MPLS Networks, draft-ietf-mpls-loss-delay-01, Feb. 2011.

   [tp-lo-de] D. Frost, S. Bryant, A Packet Loss and Delay Measurement
   Profile for MPLS-based Transport Networks, draft-frost-mpls-tp-loss-
   delay-profile-02, Feb. 2011.




10.     Informative References

   [RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
   Requirement Levels", BCP 14, RFC 2119, March 1997

   [RFC 3692] T. Narten, "Assigning Experimental and Testing Numbers
   Considered Useful", RFC 3692, Jan. 2004.

   [RFC 4775] S. Bradner, "Procedures for Protocol Extensions and
   Variations", RFC 4775, Dec. 2006.

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   MPLS-TP OAM-Toolset                                    March 2011


   [RFC 5920] L. Fang, et al, Security Framework for MPLS and GMPLS
   Networks, July 2010.

   [MPLS-TP NM REQ] Hing-Kam Lam, Scott Mansfield, Eric Gray, MPLS TP
   Network Management Requirements, draft-ietf-mpls-tp-nm-req-06.txt,
   October 2009.

   [tp-sec-fr] L. Fang, Niven-Jenkins, S. Mansfield, et. Al. MPLS-TP
   Security Framework, draft-ietf-mpls-tp-security-framework-00, Feb.
   2011.

11.     Authors' Addresses

   Luyuan Fang
   Cisco Systems
   111 Wood Avenue South
   Iselin, NJ 08830
   USA
   Email: lufang@cisco.com

   Dan Frost
   Cisco Systems
   Email: danfrost@cisco.com

   Nabil Bitar
   Verizon
   40 Sylvan Road
   Waltham, MA 02145
   USA
   Email: nabil.bitar@verizon.com

   Raymond Zhang
   British Telecom
   BT Center
   81 Newgate Street
   London, EC1A 7AJ
   United Kingdom
   Email: raymond.zhang@bt.com

   Lei Wang
   Telenor
   Telenor Norway
   Office Snaroyveien
   1331 Fornedbu
   Email: Lei.wang@telenor.com

   Kam Lee Yap

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   MPLS-TP OAM-Toolset                                    March 2011

   XO Communications
   13865 Sunrise Valley Drive,
   Herndon, VA 20171
   Email: klyap@xo.com

   Michael Fargano
   Qwest
   5325 Zuni St, 224
   Denver CO 80221-1499
   Email: Michael.Fargano@qwest.com

   John Drake
   Juniper
   Email: jdrake@juniper.net

   Thomas Nadeau
   Email: tnadeau@lucidvision.com

































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