Softwire Working Group Y. Cui
Internet-Draft Tsinghua University
Intended status: Standards Track I. Farrer
Expires: October 7, 2018 Deutsche Telekom AG
M. Boucadair
Orange
Q. Sun
L. Sun
Tsinghua University
S. Zechlin
Deutsche Telekom AG
R. Asati
Cisco Systems, Inc.
April 05, 2018
YANG Modules for IPv4-in-IPv6 Address plus Port Softwires
draft-ietf-softwire-yang-04
Abstract
This document defines YANG modules for the configuration and
operation of IPv4-in-IPv6 softwire Border Relays and Customer
Premises Equipment for the Lightweight 4over6, MAP-E, and MAP-T
softwire mechanisms.
Editorial Note (To be removed by RFC Editor)
Please update these statements with the RFC number to be assigned to
this document:
o "This version of this YANG module is part of RFC XXXX;"
o "RFC XXXX: YANG Modules for IPv4-in-IPv6 Address plus Port
Softwires";
o "reference: RFC XXXX"
Please update the "revision" date of the YANG module.
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-
Cui, et al. Expires October 7, 2018 [Page 1]
Internet-Draft YANG Modules for A+P Softwires April 2018
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 October 7, 2018.
Copyright Notice
Copyright (c) 2018 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
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. Overview of the Modules . . . . . . . . . . . . . . . . . . . 3
2.1. Overall Structure . . . . . . . . . . . . . . . . . . . . 3
2.2. Additional Components Configuration . . . . . . . . . . . 4
3. Softwire YANG CE Tree Diagram . . . . . . . . . . . . . . . . 5
3.1. CE Tree Diagram . . . . . . . . . . . . . . . . . . . . . 5
3.2. Softwire CE Tree Diagram Description . . . . . . . . . . 7
4. Softwire BR YANG Tree Diagram . . . . . . . . . . . . . . . . 8
4.1. BR Tree Diagram . . . . . . . . . . . . . . . . . . . . . 8
4.2. Softwire BR Tree Diagram Description . . . . . . . . . . 12
5. Softwire CE YANG Module . . . . . . . . . . . . . . . . . . . 13
6. BR Softwire YANG Module . . . . . . . . . . . . . . . . . . . 17
7. Common Softwire Element Groups YANG Module . . . . . . . . . 28
8. Security Considerations . . . . . . . . . . . . . . . . . . . 35
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 35
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 36
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 36
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 37
12.1. Normative References . . . . . . . . . . . . . . . . . . 37
12.2. Informative References . . . . . . . . . . . . . . . . . 38
Appendix A. Configutation Examples . . . . . . . . . . . . . . . 38
Cui, et al. Expires October 7, 2018 [Page 2]
Internet-Draft YANG Modules for A+P Softwires April 2018
A.1. Configuration Example for a lw4o6 BR Binding-Table . . . 39
A.2. Configuration Example for a MAP-E BR . . . . . . . . . . 40
A.3. lw4o6 CE Configuration Example . . . . . . . . . . . . . 42
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 45
1. Introduction
The IETF Softwire Working Group has developed several IPv4-in-IPv6
softwire mechanisms to address various deployment contexts and
constraints. As a companion to the architectural specification
documents, this document focuses on the provisioning of address plus
port (A+P) softwire functional elements: Border Routers (BRs) and
Customer Premises Equipment (CEs). The softwire mechanisms covered
in this document are Lightweight 4 over 6 [RFC7596], MAP-E [RFC7597],
and MAP-T [RFC7599].
This document defines YANG data modules [RFC7950] that can be used to
configure and manage A+P softwire elements using the NETCONF protocol
[RFC6241] for:
o Configuration
o Operational State
o Notifications
1.1. Terminology
The reader should be familiar with the concepts and terms defined in
[RFC7596], [RFC7597], [RFC7599], and the YANG data modelling language
defined in [RFC7950].
The meaning of the symbols in tree diagrams is defined in [RFC8340].
2. Overview of the Modules
2.1. Overall Structure
The document defines the following two YANG data modules for the
configuration and monitoring of softwire functional elements:
ietf-softwire-ce Provides configuration and monitoring for
softwire CE element. This module is defined as
augments to the interface YANG module
[RFC8343].
ietf-softwire-br Provides configuration and monitoring for
softwire BR element.
Cui, et al. Expires October 7, 2018 [Page 3]
Internet-Draft YANG Modules for A+P Softwires April 2018
In addition, the following module is defined:
ietf-softwire-common Contains groups of common functions that are
imported into the CE and BR modules.
This approach has been taken so that the various modules can be
easily extended to support additional softwire mechanisms, if
required.
Within the BR and CE modules, the YANG "feature" statement is used to
distinguish which of the different softwire mechanism(s) is relevant
for a specific element's configuration. For each module, a choice
statement is included for either 'binding' or 'algorithmic'.
'Binding' is used for configuring Lightweight 4over6, whereas
'Algorithmic' is used for configuring MAP-T or MAP-E.
In the 'algo-instances' container, a choice statement is included to
specify MAP-E (encapsulation) or MAP-T (translation). Table 1 shows
how these choices are used to indicate the desired softwire
mechanism:
+--------------------+-----------+---------------+
| S46 Mechanism | ce-type? | data-plane? |
+--------------------+-----------+---------------+
| Lightweight 4over6 | binding | n/a |
| MAP-E | algorithm | encapsulation |
| MAP-T | algorithm | translation |
+--------------------+-----------+---------------+
Table 1: Softwire Mechanism Choice Statement Enumeration
NETCONF notifications are also included.
Note: Earlier versions of this specification combined the softwire
mechanisms by their associated technologies rather than their
function in the architecture. As the document was revised, it
became apparent that dividing the modules by their role in the
architecture (CE or BR) was a better approach as this follows the
intended function and existing implementation approaches more
closely.
2.2. Additional Components Configuration
The softwire modules only aim to provide configuration relevant for
softwires. In order to fully provision a CE element, the following
may also be necessary:
o IPv6 forwarding and routing configuration, to enable CE to obtain
Cui, et al. Expires October 7, 2018 [Page 4]
Internet-Draft YANG Modules for A+P Softwires April 2018
one or more IPv6 prefixes for softwire usage. A YANG module for
routing management is described in [RFC8349]
o IPv4 routing configuration, to add one or more IPv4 destination
prefix(es) reachable via the configured softwire. A YANG module
for routing management is described in [RFC8349]
o Stateful NAT44/NAPT management, to optionally specify a port set
(PSID) along with its length. A YANG module for NAT management is
described in [I-D.ietf-opsawg-nat-yang]
o Stateless NAT46 management, required by softwire translation based
mechanisms (i.e. the assignment of a Network-Specific prefix to
use for IPv4/IPv6 translation). A YANG module for NAT management
is described in [I-D.ietf-opsawg-nat-yang]
As YANG modules for the above functions are already defined in other
documents, their functionality is not duplicated here and they should
be imported here, as needed. Appendix A.3 provides XML examples of
how these modules can be used together.
The CE must already have minimal IPv6 configuration in place so it is
reachable by the NETCONF client to obtain softwire configuration. If
additional IPv6 specific configuration is necessary, the YANG modules
defined in [RFC8344] and [RFC8349] may be used.
3. Softwire YANG CE Tree Diagram
3.1. CE Tree Diagram
The CE module provides configuration and monitoring for all of the
softwire mechanisms listed in Section 1.
This module augments "ietf-interfaces", defined in [RFC8343] with an
entry for the softwire. This entry can be referenced to configure
IPv4 forwarding features for the element.
Figure 1 describes the tree structure of the CE softwire YANG module.
module: ietf-softwire-ce
augment /if:interfaces/if:interface:
+--rw softwire-payload-mtu? uint16
+--rw softwire-path-mru? uint16
+--rw (ce-type)?
+--:(binding) {binding}?
| +--rw binding-ipv6info? union
| +--rw br-ipv6-addr inet:ipv6-address
+--:(algorithm) {algorithm}?
Cui, et al. Expires October 7, 2018 [Page 5]
Internet-Draft YANG Modules for A+P Softwires April 2018
+--rw algo-instances
+--rw algo-instance* [id]
+--rw id uint32
+--rw enable? boolean
+--rw algo-versioning
| +--rw version? uint64
| +--rw date? yang:date-and-time
+--rw name? string
+--rw (data-plane)?
| +--:(encapsulation)
| | +--rw br-ipv6-addr inet:ipv6-address
| +--:(translation)
| +--rw dmr-ipv6-prefix? inet:ipv6-prefix
+--rw ea-len uint8
+--rw rule-ipv6-prefix inet:ipv6-prefix
+--rw rule-ipv4-prefix inet:ipv4-prefix
+--rw forwarding boolean
augment /if:interfaces/if:interface/if:statistics:
+--ro sent-ipv4-packets?
| yang:zero-based-counter64
+--ro sent-ipv4-bytes?
| yang:zero-based-counter64
+--ro sent-ipv6-packets?
| yang:zero-based-counter64
+--ro sent-ipv6-bytes?
| yang:zero-based-counter64
+--ro rcvd-ipv4-packets?
| yang:zero-based-counter64
+--ro rcvd-ipv4-bytes?
| yang:zero-based-counter64
+--ro rcvd-ipv6-packets?
| yang:zero-based-counter64
+--ro rcvd-ipv6-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv4-packets?
| yang:zero-based-counter64
+--ro dropped-ipv4-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv6-packets?
| yang:zero-based-counter64
+--ro dropped-ipv6-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv4-fragments?
| yang:zero-based-counter64
+--ro dropped-ipv4-fragment-bytes?
| yang:zero-based-counter64
+--ro ipv6-fragments-reassembled?
| yang:zero-based-counter64
Cui, et al. Expires October 7, 2018 [Page 6]
Internet-Draft YANG Modules for A+P Softwires April 2018
+--ro ipv6-fragments-bytes-reassembled?
| yang:zero-based-counter64
+--ro out-icmpv4-error-packets?
| yang:zero-based-counter64
+--ro out-icmpv4-error-bytes?
| yang:zero-based-counter64
+--ro out-icmpv6-error-packets?
| yang:zero-based-counter64
+--ro out-icmpv6-error-bytes?
yang:zero-based-counter64
notifications:
+---n softwire-ce-event {binding}?
+--ro ce-binding-ipv6-addr-change inet:ipv6-address
Figure 1: Softwire YANG CE Tree Diagram
3.2. Softwire CE Tree Diagram Description
Additional information related to the operation of a CE element is
provided below:
o softwire-payload-mtu: optionally used to set the IPv4 MTU for the
softwire. Needed if the softwire implementation is unable to
correctly calculate the correct IPv4 Maximum Transit Unit (MTU)
size automatically.
o softwire-path-mru: optionally used to set the maximum IPv6
softwire packet size that can be received, including the
encapsulation/translation overhead. Needed if the softwire
implementation is unable to correctly calculate the correct IPv4
Maximum Receive Unit (MRU) size automatically.
o ce-type: provides a choice statement allowing the binding or
algorithmic softwire mechanisms to be selected.
Further details relevant to binding softwire elements are:
o binding-ipv6info: used to set the IPv6 binding prefix type to
identify which IPv6 address to use as the tunnel source. It can
be 'IPv6 prefix type' or ''IPv6 address type'.
o br-ipv6-addr: defines the IPv6 address of the remote BR.
Additional details relevant to some of the important algorithmic
elements are provided below:
o algo-versioning: optionally used to add an incremental version
Cui, et al. Expires October 7, 2018 [Page 7]
Internet-Draft YANG Modules for A+P Softwires April 2018
number and/or timestamp to the algorithm. This can be used for
logging/data retention purposes. The version number is
incremented and a new timestamp value written whenever a change is
made to the algorithm or a new instance is created.
o forwarding: specifies whether the rule can be used as a Forward
Mapping Rule (FMR). If not set, this rule is a Basic Mapping Rule
(BMR) only and must not be used for forwarding. Refer to
Section 4.1 of [RFC7598].
o ea-len: used to set the length of the Embedded-Address (EA), which
is defined in the mapping rule for a MAP domain.
o data-plane: provides a choice statement for either encapsulation
(MAP-E) or translation (MAP-T).
o br-ipv6-addr: defines the IPv6 address of the BR. This
information is valid for MAP-E.
o dmr-ipv6-prefix: defines the Default Mapping Rule (DMR) IPv6
prefix of the BR. This information is valid for MAP-T.
Additional information on the notification node is listed below:
o ce-binding-ipv6-addr-change: if the CE's binding-ipv6-address
changes for any reason, the NETCONF client will be notified.
4. Softwire BR YANG Tree Diagram
4.1. BR Tree Diagram
The BR YANG module provides configuration and monitoring for all of
the softwire mechanisms listed in Section 1. Figure 2 provides the
tree structure of this module.
module: ietf-softwire-br
+--rw br-instances
+--rw (br-type)?
+--:(binding) {binding}?
| +--rw binding {binding}?
| +--rw bind-instance* [id]
| +--rw binding-table-versioning
| | +--rw version? uint64
| | +--rw date? yang:date-and-time
| +--rw id uint32
| +--rw name? string
| +--rw softwire-num-threshold uint32
| +--rw softwires-payload-mtu uint16
Cui, et al. Expires October 7, 2018 [Page 8]
Internet-Draft YANG Modules for A+P Softwires April 2018
| +--rw softwire-path-mru uint16
| +--rw enable-hairpinning? boolean
| +--rw binding-table
| | +--rw binding-entry* [binding-ipv6info]
| | +--rw binding-ipv6info union
| | +--rw binding-ipv4-addr?
| | | inet:ipv4-address
| | +--rw port-set
| | | +--rw psid-offset? uint8
| | | +--rw psid-len uint8
| | | +--rw psid uint16
| | +--rw br-ipv6-addr?
| | inet:ipv6-address
| +--rw icmp-policy
| | +--rw icmpv4-errors
| | | +--rw allow-incoming-icmpv4? boolean
| | | +--rw icmpv4-rate? uint32
| | | +--rw generate-icmpv4-errors? boolean
| | +--rw icmpv6-errors
| | +--rw generate-icmpv6-errors? boolean
| | +--rw icmpv6-rate? uint32
| +--ro traffic-stat
| +--ro discontinuity-time yang:date-and-time
| +--ro sent-ipv4-packets?
| | yang:zero-based-counter64
| +--ro sent-ipv4-bytes?
| | yang:zero-based-counter64
| +--ro sent-ipv6-packets?
| | yang:zero-based-counter64
| +--ro sent-ipv6-bytes?
| | yang:zero-based-counter64
| +--ro rcvd-ipv4-packets?
| | yang:zero-based-counter64
| +--ro rcvd-ipv4-bytes?
| | yang:zero-based-counter64
| +--ro rcvd-ipv6-packets?
| | yang:zero-based-counter64
| +--ro rcvd-ipv6-bytes?
| | yang:zero-based-counter64
| +--ro dropped-ipv4-packets?
| | yang:zero-based-counter64
| +--ro dropped-ipv4-bytes?
| | yang:zero-based-counter64
| +--ro dropped-ipv6-packets?
| | yang:zero-based-counter64
| +--ro dropped-ipv6-bytes?
| | yang:zero-based-counter64
| +--ro dropped-ipv4-fragments?
Cui, et al. Expires October 7, 2018 [Page 9]
Internet-Draft YANG Modules for A+P Softwires April 2018
| | yang:zero-based-counter64
| +--ro dropped-ipv4-fragment-bytes?
| | yang:zero-based-counter64
| +--ro ipv6-fragments-reassembled?
| | yang:zero-based-counter64
| +--ro ipv6-fragments-bytes-reassembled?
| | yang:zero-based-counter64
| +--ro out-icmpv4-error-packets?
| | yang:zero-based-counter64
| +--ro out-icmpv4-error-bytes?
| | yang:zero-based-counter64
| +--ro out-icmpv6-error-packets?
| | yang:zero-based-counter64
| +--ro out-icmpv6-error-bytes?
| | yang:zero-based-counter64
| +--ro dropped-icmpv4-packets?
| | yang:zero-based-counter64
| +--ro dropped-icmpv4-bytes?
| | yang:zero-based-counter64
| +--ro hairpin-ipv4-packets?
| | yang:zero-based-counter64
| +--ro hairpin-ipv4-bytes?
| | yang:zero-based-counter64
| +--ro active-softwire-num?
| uint32
+--:(algorithm) {algorithm}?
+--rw algorithm {algorithm}?
+--rw algo-instance* [id]
+--rw id uint32
+--rw enable? boolean
+--rw algo-versioning
| +--rw version? uint64
| +--rw date? yang:date-and-time
+--rw name? string
+--rw (data-plane)?
| +--:(encapsulation)
| | +--rw br-ipv6-addr inet:ipv6-address
| +--:(translation)
| +--rw dmr-ipv6-prefix? inet:ipv6-prefix
+--rw ea-len uint8
+--rw rule-ipv6-prefix inet:ipv6-prefix
+--rw rule-ipv4-prefix inet:ipv4-prefix
+--rw forwarding boolean
+--rw port-set
| +--rw psid-offset? uint8
| +--rw psid-len uint8
| +--rw psid uint16
+--ro traffic-stat
Cui, et al. Expires October 7, 2018 [Page 10]
Internet-Draft YANG Modules for A+P Softwires April 2018
+--ro discontinuity-time yang:date-and-time
+--ro sent-ipv4-packets?
| yang:zero-based-counter64
+--ro sent-ipv4-bytes?
| yang:zero-based-counter64
+--ro sent-ipv6-packets?
| yang:zero-based-counter64
+--ro sent-ipv6-bytes?
| yang:zero-based-counter64
+--ro rcvd-ipv4-packets?
| yang:zero-based-counter64
+--ro rcvd-ipv4-bytes?
| yang:zero-based-counter64
+--ro rcvd-ipv6-packets?
| yang:zero-based-counter64
+--ro rcvd-ipv6-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv4-packets?
| yang:zero-based-counter64
+--ro dropped-ipv4-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv6-packets?
| yang:zero-based-counter64
+--ro dropped-ipv6-bytes?
| yang:zero-based-counter64
+--ro dropped-ipv4-fragments?
| yang:zero-based-counter64
+--ro dropped-ipv4-fragment-bytes?
| yang:zero-based-counter64
+--ro ipv6-fragments-reassembled?
| yang:zero-based-counter64
+--ro ipv6-fragments-bytes-reassembled?
| yang:zero-based-counter64
+--ro out-icmpv4-error-packets?
| yang:zero-based-counter64
+--ro out-icmpv4-error-bytes?
| yang:zero-based-counter64
+--ro out-icmpv6-error-packets?
| yang:zero-based-counter64
+--ro out-icmpv6-error-bytes?
yang:zero-based-counter64
notifications:
+---n softwire-binding-instance-event {binding}?
| +--ro bind-id?
| | -> /br-instances/binding/bind-instance/id
| +--ro invalid-entry* leafref
| +--ro added-entry* inet:ipv6-address
Cui, et al. Expires October 7, 2018 [Page 11]
Internet-Draft YANG Modules for A+P Softwires April 2018
| +--ro modified-entry* leafref
+---n softwire-algorithm-instance-event {algorithm}?
+--ro algo-id
| -> /br-instances/algorithm/algo-instance/id
+--ro invalid-entry-id*
| -> /br-instances/algorithm/algo-instance/id
+--ro added-entry*
| -> /br-instances/algorithm/algo-instance/id
+--ro modified-entry*
-> /br-instances/algorithm/algo-instance/id
Figure 2: Softwire YANG BR Tree
4.2. Softwire BR Tree Diagram Description
The descriptions for leaves which are common with the CE module are
provided in Figure 1. Descriptions for additional elements are
provided below:
o binding-table-versioning: optionally used to add an incremental
version number and/or timestamp to the binding table. This can be
used for logging/data retention purposes. The version number is
incremented and a new timestamp value written whenever a change is
made to the contents of the binding table or a new binding table
list is created.
o binding-entry: used to define the binding relationship between
3-tuples, which contains the lwB4's IPv6 address/prefix, the
allocated IPv4 address and restricted port-set. For detail
information, please refer to [RFC7596].
o softwire-num-threshold: used to set the maximum number of softwire
binding rules that can be created on the lw4o6 element
simultaneously.
o active-softwire-num: holds the number of softwires currently
provisioned on the element.
Additional information on some of the important notification nodes is
listed below:
o invalid-entry, added-entry, modified-entry: used to notify the
client that a specific binding entry or MAP rule has expired, been
invalidated, added, or modified.
Cui, et al. Expires October 7, 2018 [Page 12]
Internet-Draft YANG Modules for A+P Softwires April 2018
5. Softwire CE YANG Module
This module imports typedefs from [RFC6991].
<CODE BEGINS>file "ietf-softwire-ce@2018-03-16.yang"
module ietf-softwire-ce {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-softwire-ce";
prefix "softwire-ce";
import ietf-inet-types {prefix inet; }
import ietf-interfaces {prefix if; }
import iana-if-type {prefix ianaift; }
import ietf-softwire-common {prefix softwire-common; }
organization
"IETF Softwire Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/softwire/>
WG List: <mailto:softwire@ietf.org>
Qi Sun <sunqi.ietf@gmail.com>
Linhui Sun <lh.sunlinh@gmail.com>
Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Ian Farrer <ian.farrer@telekom.de>
Sladjana Zoric <sladjana.zoric@telekom.de>
Mohamed Boucadair <mohamed.boucadair@orange.com>
Rajiv <Asati rajiva@cisco.com>
";
description
"This document defines a YANG data module for the configuration and
management of A+P Softwire Customer Premises Equipment (CEs). It
covers Lightweight 4over6, MAP-E, and MAP-T mechanisms.
Copyright (c) 2018 IETF Trust and the persons identified
as authors of the code. All rights reserved.
This version of this YANG module is part of RFC XXX; see the RFC
itself for full legal notices.";
revision 2018-03-16 {
description
"Initial revision.";
reference
"RFC XXXX: YANG Modules for IPv4-in-IPv6 Address plus Port
Softwires";
}
Cui, et al. Expires October 7, 2018 [Page 13]
Internet-Draft YANG Modules for A+P Softwires April 2018
/*
* Features
*/
feature binding {
description
"Binding is used for configuring the Lightweight 4over6 mechanism.
Binding based softwire mechanisms are IPv4-over-IPv6 tunnelling
transition mechanisms specifically intended for complete
independence between the IPv6 subnet prefix (and IPv6 address)
and IPv4 address, with or without IPv4 address sharing.
This is accomplished by maintaining state for each softwire
(per-subscriber state) in the central Border Relay (BR) and using
a hub-and-spoke forwarding architecture. In order to delegate the
NAPT function and achieve IPv4 address sharing, port-restricted
IPv4 addresses needs to be allocated to CEs.
This feature indicates that the instance functions as a binding
based softwire instance.";
reference
"RFC7596: Lightweight 4over6: An Extension to the Dual-Stack Lite
Architecture
RFC7597: Mapping of Address and Port with Encapsulation (MAP-E)
RFC7599: Mapping of Address and Port using Translation (MAP-T)";
}
feature algorithm {
description
"MAP-E is an IPv6 transition mechanism for transporting IPv4
packets across an IPv6 network using IP encapsulation. MAP-E
allows for a reduction of the amount of centralized state using
rules to express IPv4/IPv6 address mappings. This introduces an
algorithmic relationship between the IPv6 subnet and IPv4 address.
MAP-T is an IPv6 transition mechanism for transporting IPv4
packets across an IPv6 network using IP translation. It leverages
a double stateless NAT64 based solution as well as the stateless
algorithmic address & transport layer port mapping algorithm
defined for MAP-E.
This feature indicates that the instance functions as a MAP-E or
MAP-T instance.";
reference
"RFC7597: Mapping of Address and Port with Encapsulation (MAP-E)
Cui, et al. Expires October 7, 2018 [Page 14]
Internet-Draft YANG Modules for A+P Softwires April 2018
RFC7599: Mapping of Address and Port using Translation (MAP-T)";
}
// Binding Entry
grouping binding-entry {
description
"The binding BR maintains an address binding table that
contains the binding between the CE's IPv6 address,
the allocated IPv4 address and restricted port-set.";
leaf binding-ipv6info {
type union {
type inet:ipv6-address;
type inet:ipv6-prefix;
}
description
"The IPv6 information for a binding entry.
When the IPv6 prefix type is used,
the IPv6 source address of the CE is constructed
according to the description in RFC7596.
If the IPv6 address type is used, the CE can use
any valid /128 address from a prefix assigned to
the CE.";
reference
"Section 5.1 of RFC7596.";
}
leaf br-ipv6-addr {
type inet:ipv6-address;
mandatory true;
description
"The IPv6 address for of the binding BR.";
}
}
// configuration and stateful parameters for CE softwire interface
augment "/if:interfaces/if:interface" {
when "if:type = 'ianaift:tunnel'";
description "CE Softwire interface configuration";
leaf softwire-payload-mtu {
type uint16;
units bytes;
description
Cui, et al. Expires October 7, 2018 [Page 15]
Internet-Draft YANG Modules for A+P Softwires April 2018
"The payload IPv4 MTU for the Softwire tunnel.";
}
leaf softwire-path-mru {
type uint16;
units bytes;
description
"The path MRU for the softwire (payload + encapsulation
overhead).";
}
choice ce-type {
description "Sets the CE softwire mechanism";
case binding {
if-feature binding;
description "CE binding configuration";
uses binding-entry;
}
case algorithm {
if-feature algorithm;
description "CE algorithm configuration";
container algo-instances {
description
"Indicates that the instances supports the MAP-E and MAP-T
function. The instances advertise the MAP-E/MAP-T
feature through the capability exchange mechanism
when a NETCONF session is established.";
list algo-instance {
key "id";
description
"MAP forwarding rule instance for
MAP-E/MAP-T";
leaf id {
type uint32;
mandatory true;
description "Algorithm Instance ID";
}
uses softwire-common:algorithm-instance;
}
}
}
}
}
augment "/if:interfaces/if:interface/if:statistics" {
Cui, et al. Expires October 7, 2018 [Page 16]
Internet-Draft YANG Modules for A+P Softwires April 2018
when "../if:type = 'ianaift:tunnel'";
description "CE Softwire interface statistics.";
uses softwire-common:traffic-stat;
}
/*
* Notifications
*/
notification softwire-ce-event {
if-feature binding;
description "CE notification";
leaf ce-binding-ipv6-addr-change {
type inet:ipv6-address;
mandatory true;
description
"If the CE's binding-ipv6-address changes for any reason,
it should notify the NETCONF client.";
}
}
}
<CODE ENDS>
6. BR Softwire YANG Module
This module imports typedefs from [RFC6991].
<CODE BEGINS>file "ietf-softwire-br@2018-03-16.yang"
module ietf-softwire-br {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-softwire-br";
prefix "softwire-br";
import ietf-inet-types {prefix inet; }
import ietf-yang-types {prefix yang; }
import ietf-softwire-common {prefix softwire-common; }
organization
"IETF Softwire Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/softwire/>
WG List: <mailto:softwire@ietf.org>
Qi Sun <sunqi.ietf@gmail.com>
Linhui Sun <lh.sunlinh@gmail.com>
Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Cui, et al. Expires October 7, 2018 [Page 17]
Internet-Draft YANG Modules for A+P Softwires April 2018
Ian Farrer <ian.farrer@telekom.de>
Sladjana Zoric <sladjana.zoric@telekom.de>
Mohamed Boucadair <mohamed.boucadair@orange.com>
Rajiv <Asati rajiva@cisco.com>
";
description
"This document defines a YANG data module for the configuration and
management of A+P Softwire Border Routers. It covers Lightweight
4over6, MAP-E, and MAP-T mechanisms.
Copyright (c) 2018 IETF Trust and the persons identified
as authors of the code. All rights reserved.
This version of this YANG module is part of RFC XXX; see the RFC
itself for full legal notices.";
revision 2018-03-16 {
description
"Initial revision.";
reference
"RFC XXXX: YANG Modules for IPv4-in-IPv6 Address plus Port
Softwires";
}
/*
* Groupings
*/
grouping port-set {
description
"Describes a set of layer 4 port numbers.
This may be a simple port range, or use the PSID algorithm
to represent a range of transport layer ports which will
be used by a NAPT.";
leaf psid-offset {
type uint8 {
range 0..16;
}
description
"The number of offset bits. In Lightweight 4over6,
the default value is 0 for assigning one contiguous
port range. In MAP-E/T, the default value is 6,
which means the system ports (0-1023) are excluded by
default and the assigned port ranges are distributed across the
entire port space, depending on either psid-len or the
number of contiguous ports.";
Cui, et al. Expires October 7, 2018 [Page 18]
Internet-Draft YANG Modules for A+P Softwires April 2018
}
leaf psid-len {
type uint8 {
range 0..15;
}
mandatory true;
description
"The length of PSID, representing the sharing
ratio for an IPv4 address. This, along with ea-len, can
be used to calculate the number of contiguous ports per
port range";
}
leaf psid {
type uint16;
mandatory true;
description
"Port Set Identifier (PSID) value, which
identifies a set of ports algorithmically.";
}
}
grouping binding-entry {
description
"The binding BR maintains an address binding table that
contains the binding between the CE's IPv6 address,
the allocated IPv4 address and restricted port-set.";
leaf binding-ipv6info {
type union {
type inet:ipv6-address;
type inet:ipv6-prefix;
}
description
"The IPv6 information for a CE binding entry.
When the IPv6 prefix type is used,
the IPv6 source address of the CE is constructed
according to the description in RFC7596;
if the IPv6 address type is used, the CE can use
any valid /128 address from a prefix assigned to
the CE.";
reference
"RFC7596: Lightweight 4over6: An Extension to the Dual-Stack
Lite Architecture";
}
leaf binding-ipv4-addr {
type inet:ipv4-address;
description
Cui, et al. Expires October 7, 2018 [Page 19]
Internet-Draft YANG Modules for A+P Softwires April 2018
"The IPv4 address assigned to the binding CE,
which is used as the IPv4 external address
for binding CE local NAPT44.";
}
container port-set {
description
"For Lightweight 4over6, the default value
for offset should be 0, to configure one contiguous
port range.";
uses port-set {
refine "psid-offset" {
default "0";
}
}
}
leaf br-ipv6-addr {
type inet:ipv6-address;
description
"The IPv6 address for binding BR.";
}
}
/*
* Features
*/
feature binding {
description
"Binding is used for configuring the Lightweight 4over6 mechanism.
Binding based softwire mechanisms are IPv4-over-IPv6 tunnelling
transition mechanisms specifically intended for complete
independence between the IPv6 subnet prefix (and IPv6 address) and
IPv4 address, with or without IPv4 address sharing.
This is accomplished by maintaining state for each softwire
(per-subscriber state) in the central Border Relay (BR) and using
a hub-and-spoke forwarding architecture. In order to delegate the
NAPT function and achieve IPv4 address sharing, port-restricted
IPv4 addresses needs to be allocated to CEs.
This feature indicates that the instance functions as a binding
based softwire instance.";
reference
"RFC7596: Lightweight 4over6: An Extension to the Dual-Stack Lite
Architecture
RFC7597: Mapping of Address and Port with Encapsulation (MAP-E)
Cui, et al. Expires October 7, 2018 [Page 20]
Internet-Draft YANG Modules for A+P Softwires April 2018
RFC7599: Mapping of Address and Port using Translation (MAP-T)";
}
feature algorithm {
description
"MAP-E is an IPv6 transition mechanism for transporting IPv4
packets across an IPv6 network using IP encapsulation. MAP-E
allows for a reduction of the amount of centralized state using
rules to express IPv4/IPv6 address mappings. This introduces an
algorithmic relationship between the IPv6 subnet and IPv4 address.
MAP-T is an IPv6 transition mechanism for transporting IPv4
packets across an IPv6 network using IP translation. It leverages
double stateless NAT64 based solution as well as the stateless
algorithmic address & transport layer port mapping algorithm
defined for MAP-E.
This feature indicates that the instance functions as a MAP-E or
MAP-T instance.";
reference
"RFC7597: Mapping of Address and Port with Encapsulation (MAP-E)
RFC7599: Mapping of Address and Port using Translation (MAP-T)";
}
container br-instances {
description
"BR Instances";
choice br-type {
description
"Select binding or algorithmic BR functionality.";
case binding {
if-feature binding;
container binding {
if-feature binding;
description
"binding mechanism (binding table) configuration.";
list bind-instance {
key "id";
description
"A set of binding BRs to be configured.";
container binding-table-versioning {
description "binding table's version";
leaf version{
type uint64;
description "Incremental version number of the binding
table";
Cui, et al. Expires October 7, 2018 [Page 21]
Internet-Draft YANG Modules for A+P Softwires April 2018
}
leaf date {
type yang:date-and-time;
description "Timestamp of the binding
table";
}
}
leaf id {
type uint32;
mandatory true;
description "An instance identifier.";
}
leaf name {
type string;
description "The name for the binding BR.";
}
leaf softwire-num-threshold {
type uint32;
mandatory true;
description
"The maximum number of softwires that can be created on
the binding BR.";
}
leaf softwires-payload-mtu {
type uint16;
units bytes;
mandatory true;
description
"The payload IPv4 MTU for binding softwire.";
}
leaf softwire-path-mru {
type uint16;
units bytes;
mandatory true;
description
"The path MRU for binding softwire.";
}
leaf enable-hairpinning {
type boolean;
default true;
description
"Enables/disables support for locally forwarding
(hairpinning) traffic between two CEs.";
reference
"RFC7596 Section 6.2";
}
container binding-table {
description "binding table";
Cui, et al. Expires October 7, 2018 [Page 22]
Internet-Draft YANG Modules for A+P Softwires April 2018
list binding-entry {
key "binding-ipv6info";
description "binding entry";
uses binding-entry;
}
}
container icmp-policy {
description
"The binding BR can be configured to process or drop
incoming ICMP messages, and to generate outgoing ICMP
error messages.";
container icmpv4-errors {
description
"ICMPv4 error processing configuration";
leaf allow-incoming-icmpv4 {
type boolean;
default true;
description
"Enables the processing of incoming ICMPv4
packets.";
reference
"RFC7596: Lightweight 4over6: An Extension to the
Dual-Stack Lite Architecture";
}
leaf icmpv4-rate {
type uint32;
description
"Rate limit threshold in messages per-second
for processing incoming ICMPv4 errors messages";
}
leaf generate-icmpv4-errors {
type boolean;
default true;
description
"Enables the generation of outgoing ICMPv4 error
messages on receipt of an inbound IPv4 packet with
no matching binding table entry.";
reference
"Seciton 5.2 of RFC7596.";
}
}
container icmpv6-errors {
description
"ICMPv6 error processing configuration";
leaf generate-icmpv6-errors {
type boolean;
Cui, et al. Expires October 7, 2018 [Page 23]
Internet-Draft YANG Modules for A+P Softwires April 2018
default true;
description
"Enables the generation of ICMPv6 errors messages if
no matching binding table entry is found for a
received packet.";
reference
"Section 6.2 of RFC7596.";
}
leaf icmpv6-rate {
type uint32;
description
"Rate limit threshold in messages per-second
for sending ICMPv6 errors messages";
reference
"Section 9 of RFC7596.";
}
}
}
container traffic-stat {
config false;
description
"Traffic statistics information for the BR.";
leaf discontinuity-time {
type yang:date-and-time;
mandatory true;
description
"The time of the most recent occasion on which the BR
instance suffered a discontinuity. This must be
initialized when the BR instance is configured
or rebooted.";
}
uses softwire-common:traffic-stat;
leaf dropped-icmpv4-packets {
type yang:zero-based-counter64;
description
"ICMPv4 packets that are dropped as a result
of the ICMP policy. Typically, this can be any
incoming ICMPv4 packets if ICMPv4 processing is
disabled or incoming ICMPv4 packets that exceed
the ICMPv4 rate-limit threshold.
Discontinuities in the value of this counter can
occur at re-initialization of the management
system, and at other times as indicated by
Cui, et al. Expires October 7, 2018 [Page 24]
Internet-Draft YANG Modules for A+P Softwires April 2018
the value of 'discontinuity-time'.";
}
leaf dropped-icmpv4-bytes {
type yang:zero-based-counter64;
description
"ICMPv4 messages, in bytes, that are dropped as
a result of the ICMP policy. Typically, it
can be any incoming ICMPv4 packets if ICMPv4
processing is disabled or incoming ICMPv4
packets that exceed the ICMPv4 rate-limit
threshold.
Discontinuities in the value of this counter can
occur at re-initialization of the management
system, and at other times as indicated by
the value of 'discontinuity-time'.";
}
leaf hairpin-ipv4-packets {
type yang:zero-based-counter64;
description
"IPv4 packets locally routed between two CEs
(hairpinned).
Discontinuities in the value of this counter can
occur at re-initialization of the management
system, and at other times as indicated by
the value of 'discontinuity-time'.";
}
leaf hairpin-ipv4-bytes {
type yang:zero-based-counter64;
description
"IPv4 bytes locally routed between two CEs
(hairpinned).
Discontinuities in the value of this counter can
occur at re-initialization of the management
system, and at other times as indicated by
the value of 'discontinuity-time'.";
}
leaf active-softwire-num {
type uint32;
config false;
description
"The number of currently active softwires on the
binding instance.
Discontinuities in the value of this counter can
occur at re-initialization of the management
Cui, et al. Expires October 7, 2018 [Page 25]
Internet-Draft YANG Modules for A+P Softwires April 2018
system, and at other times as indicated by
the value of 'discontinuity-time'.";
}
}
}
}
}
case algorithm {
if-feature algorithm;
container algorithm {
if-feature algorithm;
description
"Indicate that the instance supports the MAP-E and MAP-T
function. The instances advertise the MAP-E/MAP-T feature
through the capability exchange mechanism when a NETCONF
session is established.";
list algo-instance {
key "id";
description "Instances of algorithm";
leaf id {
type uint32;
mandatory true;
description "id";
}
uses softwire-common:algorithm-instance;
container port-set {
description "Indicates a set of ports.";
uses port-set;
}
container traffic-stat {
config false;
description
"Traffic statistics information for the BR.";
leaf discontinuity-time {
type yang:date-and-time;
mandatory true;
description
"The time of the most recent occasion on which the BR
instance suffered a discontinuity. This must be
initialized when the BR instance is configured
or rebooted.";
}
uses softwire-common:traffic-stat;
}
}
}
}
}
Cui, et al. Expires October 7, 2018 [Page 26]
Internet-Draft YANG Modules for A+P Softwires April 2018
}
/*
* Notifications
*/
notification softwire-binding-instance-event {
if-feature binding;
description "Notifications for binding instance.";
leaf bind-id {
type leafref {
path
"/br-instances/binding/"
+ "bind-instance/id";
}
description "...";
}
leaf-list invalid-entry {
type leafref {
path
"/br-instances/binding/"
+ "bind-instance[id=current()/../bind-id]/"
+ "binding-table/binding-entry/binding-ipv6info";
}
description
"Notify the client that a specific binding entry has been
expired/invalid. The binding-ipv6info identifies an entry.";
}
leaf-list added-entry {
type inet:ipv6-address;
description
"Notify the client that a binding entry has been added.
The ipv6 address of that entry is the index. The client
gets other information from the binding BR about the entry
indexed by that ipv6 address.
";
}
leaf-list modified-entry {
type leafref {
path
"/br-instances/binding/"
+ "bind-instance[id=current()/../bind-id]/"
+ "binding-table/binding-entry/binding-ipv6info";
}
description "...";
}
}
notification softwire-algorithm-instance-event {
Cui, et al. Expires October 7, 2018 [Page 27]
Internet-Draft YANG Modules for A+P Softwires April 2018
if-feature algorithm;
description "Notifications for algorithmic instance.";
leaf algo-id {
type leafref {
path
"/br-instances/algorithm/algo-instance/id";
}
mandatory true;
description "algorithmic instance event.";
}
leaf-list invalid-entry-id {
type leafref {
path
"/br-instances/algorithm/algo-instance/id";
}
description "Invalid entry event.";
}
leaf-list added-entry {
type leafref {
path
"/br-instances/algorithm/algo-instance/id";
}
description "Added entry.";
}
leaf-list modified-entry {
type leafref {
path
"/br-instances/algorithm/algo-instance/id";
}
description "Modified entry.";
}
}
}
<CODE ENDS>
7. Common Softwire Element Groups YANG Module
The following YANG module contains definitions that are used by both
the softwire CE and softwire BR YANG modules.
<CODE BEGINS>file "ietf-softwire-common@2018-03-16.yang"
module ietf-softwire-common {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-softwire-common";
prefix "softwire-common";
import ietf-inet-types { prefix inet; }
Cui, et al. Expires October 7, 2018 [Page 28]
Internet-Draft YANG Modules for A+P Softwires April 2018
import ietf-yang-types { prefix yang; }
organization
"IETF Softwire Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/softwire/>
WG List: <mailto:softwire@ietf.org>
Qi Sun <sunqi.ietf@gmail.com>
Linhui Sun <lh.sunlinh@gmail.com>
Yong Cui <yong@csnet1.cs.tsinghua.edu.cn>
Ian Farrer <ian.farrer@telekom.de>
Sladjana Zoric <sladjana.zoric@telekom.de>
Mohamed Boucadair <mohamed.boucadair@orange.com>
Rajiv <Asati rajiva@cisco.com>
";
description
"This document defines a YANG data module for the configuration and
management of A+P Softwire Customer Premises Equipment (CEs). It
covers Lightweight 4over6, MAP-E and MAP-T mechanisms.
Copyright (c) 2018 IETF Trust and the persons identified
as authors of the code. All rights reserved.
This version of this YANG module is part of RFC XXX; see the RFC
itself for full legal notices.";
revision 2018-03-16 {
description
"Initial revision.";
reference
"RFC XXXX: YANG Modules for IPv4-in-IPv6 Address plus Port
Softwires";
}
/*
* Groupings
*/
grouping algorithm-instance {
description
"Indicates that the instance supports the MAP-E and MAP-T
function. The instance advertises the MAP-E/MAP-T feature
through the capability exchange mechanism when a NETCONF
session is established.";
leaf enable {
Cui, et al. Expires October 7, 2018 [Page 29]
Internet-Draft YANG Modules for A+P Softwires April 2018
type boolean;
description
"Enable/disable an individual MAP-E or MAP-T rule.";
}
container algo-versioning {
description "algorithm's version";
leaf version {
type uint64;
description "Incremental version number for the algorithm";
}
leaf date {
type yang:date-and-time;
description "Timestamp to the algorithm";
}
}
leaf name {
type string;
description "The name for the instance.";
}
choice data-plane {
description "Selects MAP-E (encapsulation) or MAP-T
(translation)";
case encapsulation {
description "encapsulation for MAP-E";
leaf br-ipv6-addr {
type inet:ipv6-address;
mandatory true;
description
"The IPv6 address of the MAP-E BR.";
}
}
case translation {
description "translation for MAP-T";
leaf dmr-ipv6-prefix {
type inet:ipv6-prefix;
description
"The IPv6 prefix of the MAP-T BR.";
}
}
}
leaf ea-len {
type uint8;
mandatory true;
description
"Embedded Address (EA) bits are the IPv4 EA-bits in the IPv6
address identify an IPv4 prefix/address (or part thereof) or
a shared IPv4 address (or part thereof) and a port-set
identifier. The length of the EA-bits is defined as part of
Cui, et al. Expires October 7, 2018 [Page 30]
Internet-Draft YANG Modules for A+P Softwires April 2018
a MAP rule for a MAP domain.";
}
leaf rule-ipv6-prefix {
type inet:ipv6-prefix;
mandatory true;
description
"The Rule IPv6 prefix defined in the mapping rule.";
}
leaf rule-ipv4-prefix {
type inet:ipv4-prefix;
mandatory true;
description
"The Rule IPv4 prefix defined in the mapping rule.";
}
leaf forwarding {
type boolean;
mandatory true;
description
"This parameter specifies whether the rule may be used for
forwarding (FMR). If set, this rule is used as an FMR;
if not set, this rule is a Basic Mapping Rule (BMR) only
and must not be used for forwarding.";
}
}
grouping traffic-stat {
description "Traffic statistics";
leaf sent-ipv4-packets {
type yang:zero-based-counter64;
description "Number of decapsulated and forwarded IPv4 packets.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf sent-ipv4-bytes {
type yang:zero-based-counter64;
description "Decapsulated/translated IPv4 traffic sent, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf sent-ipv6-packets {
type yang:zero-based-counter64;
description "Number of encapsulated IPv6 packets sent.
Cui, et al. Expires October 7, 2018 [Page 31]
Internet-Draft YANG Modules for A+P Softwires April 2018
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf sent-ipv6-bytes {
type yang:zero-based-counter64;
description "Encapsulated IPv6 traffic sent, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf rcvd-ipv4-packets {
type yang:zero-based-counter64;
description "Number of incoming IPv4 packets at the
Internet-facing interface.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf rcvd-ipv4-bytes {
type yang:zero-based-counter64;
description "IPv4 traffic received for processing, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf rcvd-ipv6-packets {
type yang:zero-based-counter64;
description "Number of IPv4-in-IPv6 packets received
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf rcvd-ipv6-bytes {
type yang:zero-based-counter64;
description "IPv4-in-IPv6 traffic received, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
Cui, et al. Expires October 7, 2018 [Page 32]
Internet-Draft YANG Modules for A+P Softwires April 2018
other times as indicated by the value of
'discontinuity-time'.";
}
leaf dropped-ipv4-packets {
type yang:zero-based-counter64;
description "Number of IPv4 packets dropped at the
Internet-facing interface.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf dropped-ipv4-bytes {
type yang:zero-based-counter64;
description "IPv4 traffic dropped at the Internet-facing
interface, in bytes.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf dropped-ipv6-packets {
type yang:zero-based-counter64;
description "Number of IPv4-in-IPv6 packets dropped.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf dropped-ipv6-bytes {
type yang:zero-based-counter64;
description "IPv4-in-IPv6 traffic dropped, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf dropped-ipv4-fragments {
type yang:zero-based-counter64;
description "Number of fragmented IPv4 packets dropped
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
Cui, et al. Expires October 7, 2018 [Page 33]
Internet-Draft YANG Modules for A+P Softwires April 2018
'discontinuity-time'.";
}
leaf dropped-ipv4-fragment-bytes {
type yang:zero-based-counter64;
description "Fragmented IPv4 traffic dropped, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf ipv6-fragments-reassembled {
type yang:zero-based-counter64;
description "Number of IPv6 fragments successfully reassembled
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf ipv6-fragments-bytes-reassembled {
type yang:zero-based-counter64;
description "IPv6 fragments successfully reassembled, in bytes
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf out-icmpv4-error-packets {
type yang:zero-based-counter64;
description "Internally generated ICMPv4 error packets.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf out-icmpv4-error-bytes {
type yang:zero-based-counter64;
description "Internally generated ICMPv4 error messages, in bytes.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf out-icmpv6-error-packets {
Cui, et al. Expires October 7, 2018 [Page 34]
Internet-Draft YANG Modules for A+P Softwires April 2018
type yang:zero-based-counter64;
description "Internally generated ICMPv6 error packets.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
leaf out-icmpv6-error-bytes {
type yang:zero-based-counter64;
description "Internally generated ICMPv6 error messages, in bytes.
Discontinuities in the value of this counter can occur
at re-initialization of the management system, and at
other times as indicated by the value of
'discontinuity-time'.";
}
}
}
<CODE ENDS>
8. Security Considerations
The YANG module defined in this document is designed to be accessed
via network management protocols such as NETCONF [RFC6241] or
RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport
layer, and the mandatory-to-implement secure transport is Secure
Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the
mandatory-to-implement secure transport is TLS [RFC5246].
The NETCONF access control model [RFC8341] provides the means to
restrict access for particular NETCONF or RESTCONF users to a
preconfigured subset of all available NETCONF or RESTCONF protocol
operations and content.
All data nodes defined in the YANG modules which can be created,
modified, and deleted (i.e., config true, which is the default) are
considered sensitive. Write operations (e.g., edit-config) applied
to these data nodes without proper protection can negatively affect
network operations.
9. IANA Considerations
This document requests IANA to register the following URIs in the
"IETF XML Registry" [RFC3688].
Cui, et al. Expires October 7, 2018 [Page 35]
Internet-Draft YANG Modules for A+P Softwires April 2018
URI: urn:ietf:params:xml:ns:yang:softwire-ce
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:softwire-br
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:softwire-common
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
This document requests that IANA registers the following YANG modules
in the "YANG Module Names" registry [RFC7950].
name: ietf-softwire-ce
namespace: urn:ietf:params:xml:ns:yang:softwire-ce
prefix: softwire-ce
reference: RFC XXXX
name: ietf-softwire-br
namespace: urn:ietf:params:xml:ns:yang:softwire-br
prefix: softwire-br
reference: RFC XXXX
name: ietf-softwire-common
namespace: urn:ietf:params:xml:ns:yang:softwire-common
prefix: softwire-br
reference: RFC XXXX
10. Acknowledgements
The authors would like to thank Lishan Li, Bert Wijnen, Giles Heron,
Ole Troan, Andy Wingo and Leo Tietz for their contributions to this
work.
11. Contributors
The following individuals contributed to this document:
Hao Wang
Tsinghua University
Beijing 100084
P.R.China
Phone: +86-10-6278-5822
Email: wangh13@mails.tsinghua.edu.cn
Cui, et al. Expires October 7, 2018 [Page 36]
Internet-Draft YANG Modules for A+P Softwires April 2018
12. References
12.1. Normative References
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC7596] Cui, Y., Sun, Q., Boucadair, M., Tsou, T., Lee, Y., and I.
Farrer, "Lightweight 4over6: An Extension to the Dual-
Stack Lite Architecture", RFC 7596, DOI 10.17487/RFC7596,
July 2015, <https://www.rfc-editor.org/info/rfc7596>.
[RFC7597] Troan, O., Ed., Dec, W., Li, X., Bao, C., Matsushima, S.,
Murakami, T., and T. Taylor, Ed., "Mapping of Address and
Port with Encapsulation (MAP-E)", RFC 7597,
DOI 10.17487/RFC7597, July 2015,
<https://www.rfc-editor.org/info/rfc7597>.
[RFC7598] Mrugalski, T., Troan, O., Farrer, I., Perreault, S., Dec,
W., Bao, C., Yeh, L., and X. Deng, "DHCPv6 Options for
Configuration of Softwire Address and Port-Mapped
Clients", RFC 7598, DOI 10.17487/RFC7598, July 2015,
<https://www.rfc-editor.org/info/rfc7598>.
[RFC7599] Li, X., Bao, C., Dec, W., Ed., Troan, O., Matsushima, S.,
and T. Murakami, "Mapping of Address and Port using
Translation (MAP-T)", RFC 7599, DOI 10.17487/RFC7599, July
2015, <https://www.rfc-editor.org/info/rfc7599>.
[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>.
Cui, et al. Expires October 7, 2018 [Page 37]
Internet-Draft YANG Modules for A+P Softwires April 2018
[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>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
12.2. Informative References
[I-D.ietf-opsawg-nat-yang]
Boucadair, M., Sivakumar, S., Jacquenet, C., Vinapamula,
S., and Q. Wu, "A YANG Module for Network Address
Translation (NAT) and Network Prefix Translation (NPT)",
draft-ietf-opsawg-nat-yang-14 (work in progress), March
2018.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[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>.
[RFC8344] Bjorklund, M., "A YANG Data Model for IP Management",
RFC 8344, DOI 10.17487/RFC8344, March 2018,
<https://www.rfc-editor.org/info/rfc8344>.
[RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
Routing Management (NMDA Version)", RFC 8349,
DOI 10.17487/RFC8349, March 2018,
<https://www.rfc-editor.org/info/rfc8349>.
Appendix A. Configutation Examples
The following sections provide examples of how the softwire YANG
modules can be used for configuring softwire elements.
Cui, et al. Expires October 7, 2018 [Page 38]
Internet-Draft YANG Modules for A+P Softwires April 2018
A.1. Configuration Example for a lw4o6 BR Binding-Table
The lwAFTR maintains an address binding table which contains the
following 3-tuples:
o IPv6 Address for a single lwB4
o Public IPv4 Address
o Restricted port-set
The entry has two functions: the IPv6 encapsulation of inbound IPv4
packets destined to the lwB4 and the validation of outbound IPv4-in-
IPv6 packets received from the lwB4 for de-capsulation.
Consider an example for the following lw4o6 binding table entry:
lwB4 Binding IPv6 Address: 2001:db8::1
lwB4 Binding IPv4 Address: 192.0.2.1
lwB4 IPv6 Address: 123
lwB4 PSID Length 8
BR IPv6 Address: 2001:db8:1::2
Cui, et al. Expires October 7, 2018 [Page 39]
Internet-Draft YANG Modules for A+P Softwires April 2018
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<softwire-config xmlns="urn:ietf:params:xml:ns:yang:ietf-softwire-br">
<br-instances>
<binding>
<br-instance>
<id>1</id>
<binding-table>
<binding-entry>
<binding-ipv6info>2001:db8::1</binding-ipv6info>
<binding-ipv4-addr>192.0.2.1</binding-ipv4-addr>
<port-set>
<psid>123</psid>
<psid-len>8</psid-len>
</port-set>
<br-ipv6-addr>2001:db8:1::2</br-ipv6-addr>
</binding-entry>
</binding-table>
<softwire-num-threshold>1024</softwire-num-threshold>
<softwire-path-mru>1540</softwire-path-mru>
<softwire-payload-mtu>1500</softwire-payload-mtu>
</br-instance>
</binding>
</br-instances>
</softwire-config>
</config>
Figure 3: lw4o6 Binding-Table Configuration XML
A.2. Configuration Example for a MAP-E BR
A MAP-E BR is configured with forward mapping rules for the clients
it is serving. In this example (taken from [RFC7597], Appendix A,
Example 2), the following parameters are required:
o Rule IPv6 Prefix
o Rule IPv4 Prefix
o Rule EA-bit bit length
o IPv6 Address of MAP-BR
The mapping rule has two functions: identifying the destination CE
IPv6 address for encapsulating inbound IPv4 packets and the
validation of outbound IPv4-in-IPv6 packets received from the CE for
de-capsulation.
Cui, et al. Expires October 7, 2018 [Page 40]
Internet-Draft YANG Modules for A+P Softwires April 2018
The transport type for the data plane also needs to be configured for
encapsulation to enable MAP-E and forwarding needs to be enabled.
Consider an example for the following MAP-E Forwarding Mapping Rule:
Data plane: encapsulation
Rule IPv6 Prefix: 2001:db8::/40
Rule IPv4 Prefix: 192.0.2.0/24
Rule EA-bit Length: 16
BR IPv6 Address: 2001:db8:ffff::1
Here is the example MAP-E BR configuration xml:
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<softwire-config xmlns="urn:ietf:params:xml:ns:yang:ietf-softwire-br">
<br-instances>
<algorithm>
<algo-instance>
<id>42</id>
<algo-instances>
<algo-instance>
<id>1234</id>
<data-plane>encapsulation</data-plane>
<ea-len>16</ea-len>
<rule-ipv4-prefix>192.0.2.0/24</rule-ipv4-prefix>
<rule-ipv6-prefix>2001:db8::/40</rule-ipv6-prefix>
<forwarding>true</forwarding>
<br-ipv6-addr>2001:db8:ffff::1</br-ipv6-addr>
<psid-offset>6</psid-offset>
<psid-len>8</psid-len>
</algo-instance>
</algo-instances>
</algo-instance>
</algorithm>
</br-instances>
</softwire-config>
</config>
Figure 4: MAP-E FMR Configuration XML
Cui, et al. Expires October 7, 2018 [Page 41]
Internet-Draft YANG Modules for A+P Softwires April 2018
A.3. lw4o6 CE Configuration Example
The following section provides XML examples for configuring a lw4o6
CE. Examples for routing and NAT44 are also provided for
convienience.
Consider an example for the following lw4o6 CE Configuration:
lwB4 Binding IPv6 Address: 2001:db8::1
lwB4 Binding IPv4 Address: 192.0.2.1
lwB4 IPv6 Address: 123
lwB4 PSID Length 8
BR IPv6 Address: 2001:db8:1::2
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface>
<name>lw4o6-wan</name>
<type
xmlns:iana="urn:ietf:params:xml:ns:yang:iana-if-type">
iana:tunnel
</type>
<ce-interface
xmlns="urn:ietf:params:xml:ns:yang:ietf-softwire-ce">
<br-ipv6-addr>2001:db8:1::2</br-ipv6-addr>
<binding-ipv6info>2001:db8::1</binding-ipv6info>
</ce-interface>
</interface>
</interfaces>
</config>
Figure 5: lw4o6 CE Configuration XML
In the above example, the interface name is defined for the softwire
tunnel. This name is then referenced by the routing configuration
for the IPv4 route. The following section provides example
configuration for the CE's IPv4 routing, using the YANG module
described in [RFC8349].
Cui, et al. Expires October 7, 2018 [Page 42]
Internet-Draft YANG Modules for A+P Softwires April 2018
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type>static</type>
<name>v4</name>
<static-routes>
<ipv4
xmlns="urn:ietf:params:xml:ns:yang:ietf-ipv4-unicast-routing">
<route>
<destination-prefix>0.0.0.0/0</destination-prefix>
<next-hop>
<outgoing-interface>lw4o6-wan</outgoing-interface>
</next-hop>
</route>
</ipv4>
</static-routes>
</control-plane-protocol>
</control-plane-protocols>
</routing>
</config>
Figure 6: lw4o6 CE Routing Configuration XML
The following section provides example configuration for the CE's
NAPT44 function, using the YANG module described in
[I-D.ietf-opsawg-nat-yang].
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<nat xmlns="urn:ietf:params:xml:ns:yang:ietf-nat">
<instances>
<instance>
<id>1</id>
<policy>
<policy-id>1</policy-id>
<external-ip-address-pool>
<pool-id>1</pool-id>
<external-ip-pool>192.0.2.1</external-ip-pool>
</external-ip-address-pool>
<port-set-restrict>
<port-set-algo>
<psid-offset>6</psid-offset>
<psid-len>8</psid-len>
<psid>52</psid>
</port-set-algo>
</port-set-restrict>
<notify-pool-usage>
<pool-id>1</pool-id>
Cui, et al. Expires October 7, 2018 [Page 43]
Internet-Draft YANG Modules for A+P Softwires April 2018
<high-threshold>80</high-threshold>
</notify-pool-usage>
</policy>
<mapping-limits>
<limit-per-protocol>
<protocol-id>1</protocol-id>
<limit>8</limit>
</limit-per-protocol>
<limit-per-protocol>
<protocol-id>6</protocol-id>
<limit>32</limit>
</limit-per-protocol>
<limit-per-protocol>
<protocol-id>17</protocol-id>
<limit>16</limit>
</limit-per-protocol>
</mapping-limits>
<mapping-table>
<mapping-entry>
<index>1</index>
<external-src-address>192.0.2.1/32</external-src-address>
<internal-src-address>192.168.1.0/24</internal-src-address>
<transport-protocol>6</transport-protocol>
</mapping-entry>
<mapping-entry>
<index>2</index>
<external-src-address>192.0.2.1/32</external-src-address>
<internal-src-address>192.168.1.0/24</internal-src-address>
<transport-protocol>17</transport-protocol>
</mapping-entry>
<mapping-entry>
<index>3</index>
<external-src-address>192.0.2.1/32</external-src-address>
<internal-src-address>192.168.1.0/24</internal-src-address>
<transport-protocol>1</transport-protocol>
</mapping-entry>
</mapping-table>
</instance>
</instances>
</nat>
</config>
Figure 7: lw4o6 NAT Configuration XML
Cui, et al. Expires October 7, 2018 [Page 44]
Internet-Draft YANG Modules for A+P Softwires April 2018
Authors' Addresses
Yong Cui
Tsinghua University
Beijing 100084
P.R. China
Phone: +86-10-6260-3059
Email: yong@csnet1.cs.tsinghua.edu.cn
Ian Farrer
Deutsche Telekom AG
CTO-ATI,Landgrabenweg 151
Bonn, NRW 53227
Germany
Email: ian.farrer@telekom.de
Mohamed Boucadair
Orange
Rennes 35000
France
Email: mohamed.boucadair@orange.com
Qi Sun
Tsinghua University
Beijing 100084
P.R. China
Phone: +86-10-6278-5822
Email: sunqi.ietf@gmail.com
Linhui Sun
Tsinghua University
Beijing 100084
P.R. China
Phone: +86-10-6278-5822
Email: lh.sunlinh@gmail.com
Cui, et al. Expires October 7, 2018 [Page 45]
Internet-Draft YANG Modules for A+P Softwires April 2018
Sladjana Zechlin
Deutsche Telekom AG
Landgrabenweg 151
Bonn, NRW 53227
Germany
Email: sladjana.zechlin@telekom.de
Rajiv Asati
Cisco Systems, Inc.
7025 Kit Creek Rd.
RTP, NC 27709
USA
Email: Rajiva@cisco.com
Cui, et al. Expires October 7, 2018 [Page 46]