Internet DRAFT - draft-ietf-spring-sr-yang
draft-ietf-spring-sr-yang
SPRING Working Group S. Litkowski
Internet-Draft Cisco Systems
Intended status: Standards Track Y. Qu
Expires: July 29, 2021 Futurewei
A. Lindem
Cisco Systems
P. Sarkar
Arrcus Networks
J. Tantsura
Apstra
January 25, 2021
YANG Data Model for Segment Routing
draft-ietf-spring-sr-yang-30
Abstract
This document defines a YANG data model for segment routing
configuration and operation, which is to be augmented by different
segment routing data planes. The document also defines a YANG model
that is intended to be used on network elements to configure or
operate the segment routing MPLS data plane, as well as some generic
containers to be reused by IGP protocol modules to support segment
routing.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 29, 2021.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
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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 . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology and Notation . . . . . . . . . . . . . . . . . . 3
2.1. Tree diagram . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Prefixes in Data Node Names . . . . . . . . . . . . . . . 3
3. Design of the Data Model . . . . . . . . . . . . . . . . . . 3
4. Configuration . . . . . . . . . . . . . . . . . . . . . . . . 6
5. IGP Control plane configuration . . . . . . . . . . . . . . . 6
5.1. IGP interface configuration . . . . . . . . . . . . . . . 7
5.1.1. Adjacency SID properties . . . . . . . . . . . . . . 7
5.1.1.1. Bundling . . . . . . . . . . . . . . . . . . . . 7
5.1.1.2. Protection . . . . . . . . . . . . . . . . . . . 8
6. State Data . . . . . . . . . . . . . . . . . . . . . . . . . 8
7. Notifications . . . . . . . . . . . . . . . . . . . . . . . . 8
8. YANG Modules . . . . . . . . . . . . . . . . . . . . . . . . 8
8.1. YANG Module for Segment Routing . . . . . . . . . . . . . 9
8.2. YANG Module for Segment Routing Common Types . . . . . . 10
8.3. YANG Module for Segment Routing MPLS . . . . . . . . . . 16
9. Security Considerations . . . . . . . . . . . . . . . . . . . 27
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 29
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 29
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 30
12.1. Normative References . . . . . . . . . . . . . . . . . . 30
12.2. Informative References . . . . . . . . . . . . . . . . . 32
Appendix A. Configuration examples . . . . . . . . . . . . . . . 32
A.1. SR MPLS with IPv4 . . . . . . . . . . . . . . . . . . . . 32
A.2. SR MPLS with IPv6 . . . . . . . . . . . . . . . . . . . . 35
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 38
1. Introduction
This document defines a YANG data model [RFC7950] for segment routing
[RFC8402] configuration and operation. The document also defines a
YANG model that is intended to be used on network elements to
configure or operate the segment routing MPLS data plane [RFC8660].
This document does not define the IGP extensions to support segment
routing but defines generic groupings to be reused by IGP extension
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modules. The reason of this design choice is to not require
implementations to support all IGP extensions. For example, an
implementation may support the IS-IS extension but not the OSPF
extension.
The YANG modules in this document conform to the Network Management
Datastore Architecture (NMDA) [RFC8342].
2. Terminology and Notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2.1. Tree diagram
Tree diagrams used in this document follow the notation defined in
[RFC8340].
2.2. Prefixes in Data Node Names
In this document, names of data nodes, actions, and other data model
objects are often used without a prefix, as long as it is clear from
the context in which YANG module each name is defined. Otherwise,
names are prefixed using the standard prefix associated with the
corresponding YANG module, as shown in Table 1.
+----------+--------------------+-----------+
| Prefix | YANG module | Reference |
+----------+--------------------+-----------+
| if | ietf-interfaces | [RFC8343] |
| rt | ietf-routing | [RFC8349] |
| rt-types | ietf-routing-types | [RFC8294] |
| yang | ietf-yang-types | [RFC6991] |
| inet | ietf-inet-types | [RFC6991] |
+----------+--------------------+-----------+
Table 1: Prefixes and Corresponding YANG Modules
3. Design of the Data Model
Module ietf-segment-routing augments the routing container in the
ietf-routing model [RFC8349], and defines generic segment routing
configuration and operational state. This module is augmented by
modules supporting different data planes.
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Module ietf-segment-routing-mpls augments ietf-segment-routing, and
supports SR MPLS data plane configuration and operational state.
Module ietf-segment-routing-common defines generic types and
groupings that SHOULD be reused by IGP extension modules.
module: ietf-segment-routing
augment /rt:routing:
+--rw segment-routing
module: ietf-segment-routing-mpls
augment /rt:routing/sr:segment-routing:
+--rw sr-mpls
+--rw bindings
| +--rw mapping-server {mapping-server}?
| | +--rw policy* [name]
| | +--rw name string
| | +--rw entries
| | +--rw mapping-entry* [prefix algorithm]
| | +--rw prefix inet:ip-prefix
| | +--rw value-type? enumeration
| | +--rw start-sid uint32
| | +--rw range? uint32
| | +--rw algorithm identityref
| +--rw connected-prefix-sid-map
| | +--rw connected-prefix-sid* [prefix algorithm]
| | +--rw prefix inet:ip-prefix
| | +--rw value-type? enumeration
| | +--rw start-sid uint32
| | +--rw range? uint32
| | +--rw algorithm identityref
| | +--rw last-hop-behavior? enumeration
| +--rw local-prefix-sid
| +--rw local-prefix-sid* [prefix algorithm]
| +--rw prefix inet:ip-prefix
| +--rw value-type? enumeration
| +--rw start-sid uint32
| +--rw range? uint32
| +--rw algorithm identityref
+--rw srgb
| +--rw srgb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--rw srlb
| +--rw srlb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--ro label-blocks* []
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| +--ro lower-bound? uint32
| +--ro upper-bound? uint32
| +--ro size? uint32
| +--ro free? uint32
| +--ro used? uint32
| +--ro scope? enumeration
+--ro sid-db
+--ro sid* [target sid source source-protocol binding-type]
+--ro target string
+--ro sid uint32
+--ro algorithm? uint8
+--ro source inet:ip-address
+--ro used? boolean
+--ro source-protocol -> /rt:routing
/control-plane-protocols
/control-plane-protocol/name
+--ro binding-type enumeration
+--ro scope? enumeration
notifications:
+---n segment-routing-srgb-collision
| +--ro srgb-collisions* []
| +--ro lower-bound? uint32
| +--ro upper-bound? uint32
| +--ro routing-protocol? -> /rt:routing
| /control-plane-protocols
| /control-plane-protocol/name
| +--ro originating-rtr-id? router-or-system-id
+---n segment-routing-global-sid-collision
| +--ro received-target? string
| +--ro new-sid-rtr-id? router-or-system-id
| +--ro original-target? string
| +--ro original-sid-rtr-id? router-or-system-id
| +--ro index? uint32
| +--ro routing-protocol? -> /rt:routing
| /control-plane-protocols
| /control-plane-protocol/name
+---n segment-routing-index-out-of-range
+--ro received-target? string
+--ro received-index? uint32
+--ro routing-protocol? -> /rt:routing
/control-plane-protocols
/control-plane-protocol/name
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4. Configuration
The module ietf-segment-routing-mpls augments the "/rt:routing/
sr:segment-routing:" with an sr-mpls container. This container
defines all the configuration parameters related to the segment-
routing MPLS data plane.
The sr-mpls configuration is split in global configuration and
interface configuration.
The global configuration includes :
o bindings : Defines prefix to SID mappings. The operator can
control advertisement of Prefix-SID independently for IPv4 and
IPv6. Two types of mappings are available:
* Mapping-server : maps non local prefixes to a segment ID.
Configuration of bindings does not automatically allow
advertisement of those bindings. Advertisement must be
controlled by each routing-protocol instance (see Section 5).
Multiple mapping policies may be defined.
* Connected prefixes : maps connected prefixes to a segment ID.
Advertisement of the mapping will be done by IGP when enabled
for segment routing (see Section 5). The SID value can be
expressed as an index (default), or an absolute value. The
"last-hop-behavior" configuration dictates the MPLS PHP
behavior: "explicit-null", "php", or "non-php".
o SRGB (Segment Routing Global Block): Defines a list of label
blocks represented by a pair of lower-bound/upper-bound labels.
The SRGB is also agnostic to the control plane used. So all
routing-protocol instance will have to advertise the same SRGB.
o SRLB (Segment Routing Local Block): Defines a list of label blocks
represented by a pair of lower-bound/upper-bound labels, reserved
for local SIDs.
5. IGP Control plane configuration
Support of segment-routing extensions for a particular IGP control
plane is done by augmenting routing-protocol configuration with
segment-routing extensions. This augmentation SHOULD be part of
separate YANG modules in order to not create any dependency for
implementations to support all protocol extensions.
This module defines groupings that SHOULD be used by IGP segment
routing modules.
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The "sr-control-plane" grouping defines the generic global
configuration for the IGP.
The "enabled" leaf enables segment-routing extensions for the
routing-protocol instance.
The "bindings" container controls the routing-protocol instance's
advertisement of local bindings and the processing of received
bindings.
5.1. IGP interface configuration
The interface configuration is part of the "igp-interface" grouping
and includes Adjacency SID properties.
5.1.1. Adjacency SID properties
5.1.1.1. Bundling
In case of parallel IP links between routers, an additional Adjacency
SID [RFC8402] may be advertised representing more than one adjacency
(i.e., a bundle of adjacencies). The "advertise-adj-group-sid"
configuration controls controls for which group(s) an additional
adjacency SID is advertised.
The "advertise-adj-group-sid" is a list of "group-id". The "group-
id" will identify interfaces that are bundled together.
+-------+ +------+
| | ------- L1 ---- | |
| R1 | ------- L2 ---- | R2 |
| | ------- L3 ---- | |
| | ------- L4 ---- | |
+-------+ +------+
In the figure above, R1 and R2 are interconnected by four links. A
routing protocol adjacency is established on each link. Operator
would like to create segment-routing Adj-SIDs that represent some
bundles of links. We can imagine two different bundles : L1/L2 and
L3/L4. To achieve this behavior, the service provider will configure
a "group-id" X for both interfaces L1 and L2 and a "group-id" Y for
both interfaces L3 and L4. This will result in R1 advertising an
additional an Adj-SID for each adjacency, for example an Adj-SID with
a value of 400 will be added to L1 and L2. An Adj-SID and a value of
500 will be added to L3 and L4. As L1/L2 and L3/L4 does not share
the same "group-id", a different SID value will be allocated.
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5.1.1.2. Protection
The "advertise-protection" defines how protection for an interface is
advertised. It does not control the activation or deactivation of
protection. If the "single" option is used, a single Adj-SID will be
advertised for the interface. If the interface is protected, the
B-Flag for the Adj-SID advertisement will be set. If the "dual"
option is used and if the interface is protected, two Adj-SIDs will
be advertised for the interface adjacencies. One Adj-SID will always
have the B-Flag set and the other will have the B-Flag clear. This
option is intended to be used in the case of traffic engineering
where a path must use either protected segments or non-protected
segments.
6. State Data
The operational states contain information reflecting the usage of
allocated SRGB labels.
It also includes a list of all global SIDs, their associated
bindings, and other information such as the source protocol and
algorithm.
7. Notifications
The model defines the following notifications for segment-routing.
o segment-routing-srgb-collision: Raised when a control plane
advertised SRGB blocks have conflicts.
o segment-routing-global-sid-collision: Raised when a control plane
advertised index is already associated with another target (in
this version, the only defined targets are IPv4 and IPv6
prefixes).
o segment-routing-index-out-of-range: Raised when a control plane
advertised index falls outside the range of SRGBs configured for
the network device.
8. YANG Modules
There are three YANG modules included in this document.
The following RFCs and drafts are not referenced in the document text
but are referenced in the ietf-segment-routing.yang, ietf-segment-
routing-common.yang, and/or ietf-segment-routing-mpls.yang modules:
[RFC6991], [RFC8294], [RFC8476], [RFC8491], [RFC8665], [RFC8667],
[RFC8669], and [RFC8814].
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8.1. YANG Module for Segment Routing
ietf-segment-routing.yang: This module defines a generic framework
for Segment Routing, and it is to be augmented by models for
different SR data planes.
<CODE BEGINS> file "ietf-segment-routing@2021-01-25.yang"
module ietf-segment-routing {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-segment-routing";
prefix sr;
import ietf-routing {
prefix rt;
reference "RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
organization
"IETF SPRING - SPRING Working Group";
contact
"WG Web: <https://tools.ietf.org/wg/spring/>
WG List: <mailto:spring@ietf.org>
Author: Stephane Litkowski
<mailto:slitkows.ietf@gmail.com>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Pushpasis Sarkar
<mailto:pushpasis.ietf@gmail.com>
Author: Jeff Tantsura
<jefftant.ietf@gmail.com>
";
description
"The YANG module defines a generic framework for Segment
Routing. It is to be augmented by models for different
SR data planes.
This YANG model conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8242.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
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without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX;
see the RFC itself for full legal notices.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
'MAY', and 'OPTIONAL' in this document are to be interpreted as
described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
revision 2021-01-25 {
description
"Initial Version";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
}
augment "/rt:routing" {
description
"This module augments routing data model (RFC 8349)
with Segment Routing (SR).";
container segment-routing {
description
"Segment Routing configuration. This container
is to be augmented by models for different SR
data planes.";
reference "RFC 8402: Segment Routing Architecture.";
}
}
}
<CODE ENDS>
8.2. YANG Module for Segment Routing Common Types
ietf-segment-routing-common.yang: This module defines a collection of
generic types and groupings for SR as defined in [RFC8402].
<CODE BEGINS> file "ietf-segment-routing-common@2021-01-25.yang"
module ietf-segment-routing-common {
yang-version 1.1;
namespace
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"urn:ietf:params:xml:ns:yang:ietf-segment-routing-common";
prefix sr-cmn;
import ietf-inet-types {
prefix inet;
reference "RFC 6991: Common YANG Data Types";
}
organization
"IETF SPRING - SPRING Working Group";
contact
"WG Web: <https://tools.ietf.org/wg/spring/>
WG List: <mailto:spring@ietf.org>
Author: Stephane Litkowski
<mailto:slitkows.ietf@gmail.com>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Pushpasis Sarkar
<mailto:pushpasis.ietf@gmail.com>
Author: Jeff Tantsura
<jefftant.ietf@gmail.com>
";
description
"The YANG module defines a collection of generic types and
groupings for Segment Routing (SR) as described in RFC 8402.
This YANG model conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8242.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX;
see the RFC itself for full legal notices.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
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NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
'MAY', and 'OPTIONAL' in this document are to be interpreted as
described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
revision 2021-01-25 {
description
"Initial version";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
}
feature sid-last-hop-behavior {
description
"Configurable last hop behavior.";
reference "RFC 8660: Segment Routing with the MPLS Data Plane";
}
identity prefix-sid-algorithm {
description
"Base identity for prefix-sid algorithm.";
reference "RFC 8402: Segment Routing Architecture";
}
identity prefix-sid-algorithm-shortest-path {
base prefix-sid-algorithm;
description
"Shortest Path First (SPF) prefix-sid algorithm. This
is the default algorithm.";
}
identity prefix-sid-algorithm-strict-spf {
base prefix-sid-algorithm;
description
"This algorithm mandates that the packet is forwarded
according to ECMP-aware SPF algorithm.";
}
grouping srlr {
description
"Grouping for SR Label Range configuration.";
leaf lower-bound {
type uint32;
description
"Lower value in the label range.";
}
leaf upper-bound {
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type uint32;
must "../lower-bound < ../upper-bound" {
error-message
"The upper-bound must be greater than the lower-bound.";
description
"The value must be greater than 'lower-bound'.";
}
description
"Upper value in the label range.";
}
}
grouping srgb {
description
"Grouping for SR Global Label range.";
list srgb {
key "lower-bound upper-bound";
ordered-by user;
description
"List of global blocks to be advertised.";
uses srlr;
}
}
grouping srlb {
description
"Grouping for SR Local Block range.";
list srlb {
key "lower-bound upper-bound";
ordered-by user;
description
"List of SRLBs.";
uses srlr;
}
}
grouping sid-value-type {
description
"Defines how the SID value is expressed.";
leaf value-type {
type enumeration {
enum "index" {
description
"The value will be interpreted as an index.";
}
enum "absolute" {
description
"The value will become interpreted as an absolute
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value.";
}
}
default "index";
description
"This leaf defines how value must be interpreted.";
}
}
grouping prefix-sid {
description
"This grouping defines cfg of prefix SID.";
leaf prefix {
type inet:ip-prefix;
description
"connected prefix sid.";
}
uses prefix-sid-attributes;
}
grouping ipv4-sid {
description
"Grouping for an IPv4 prefix SID.";
leaf prefix {
type inet:ipv4-prefix;
description
"Connected IPv4 prefix sid.";
}
uses prefix-sid-attributes;
}
grouping ipv6-sid {
description
"Grouping for an IPv6 prefix SID.";
leaf prefix {
type inet:ipv6-prefix;
description
"Connected ipv6 prefix sid.";
}
uses prefix-sid-attributes;
}
grouping last-hop-behavior {
description
"Defines last hop behavior";
leaf last-hop-behavior {
if-feature "sid-last-hop-behavior";
type enumeration {
enum "explicit-null" {
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description
"Use explicit-null for the SID.";
}
enum "no-php" {
description
"Do not use MPLS Penultimate Hop Popping (PHP)
for the SID.";
}
enum "php" {
description
"Use MPLS PHP for the SID.";
}
}
description
"Configure last hop behavior.";
}
}
grouping prefix-sid-attributes {
description
"Grouping for Segment Routing (SR) prefix attributes.";
uses sid-value-type;
leaf start-sid {
type uint32;
mandatory true;
description
"Value associated with prefix. The value must be
interpreted in the context of value-type.";
}
leaf range {
type uint32;
description
"Indicates how many SIDs can be allocated.";
}
leaf algorithm {
type identityref {
base prefix-sid-algorithm;
}
description
"Prefix-sid algorithm.";
}
}
}
<CODE ENDS>
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8.3. YANG Module for Segment Routing MPLS
ietf-segment-routing-mpls.yang: This module defines the configuration
and operational states for the Segment Routing MPLS data plane.
<CODE BEGINS> file "ietf-segment-routing-mpls@2021-01-25.yang"
module ietf-segment-routing-mpls {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls";
prefix sr-mpls;
import ietf-inet-types {
prefix inet;
reference "RFC 6991: Common YANG Data Types";
}
import ietf-routing {
prefix rt;
reference "RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-routing-types {
prefix rt-types;
reference "RFC 8294: Common YANG Data Types for the
Routing Area";
}
import ietf-segment-routing {
prefix sr;
reference "RFC XXXX: YANG Data Model for Segment Routing.";
}
import ietf-segment-routing-common {
prefix sr-cmn;
reference "RFC XXXX: YANG Data Model for Segment Routing.";
}
organization
"IETF SPRING - SPRING Working Group";
contact
"WG Web: <https://tools.ietf.org/wg/spring/>
WG List: <mailto:spring@ietf.org>
Author: Stephane Litkowski
<mailto:slitkows.ietf@gmail.com>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Pushpasis Sarkar
<mailto:pushpasis.ietf@gmail.com>
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Author: Jeff Tantsura
<jefftant.ietf@gmail.com>
";
description
"The YANG module defines a generic configuration model for
the Segment Routing MPLS data plane.
This YANG model conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8242.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX;
see the RFC itself for full legal notices.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
'MAY', and 'OPTIONAL' in this document are to be interpreted as
described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
revision 2021-01-25 {
description
"Initial Version";
reference "RFC XXXX: YANG Data Model for Segment Routing.";
}
feature mapping-server {
description
"Support for Segment Routing Mapping Server (SRMS).";
reference "RFC 8661: Segment Routing MPLS Interworking
with LDP";
}
feature protocol-srgb {
description
"Support for per-protocol Segment Routing Global Block
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(SRGB) configuration.";
reference "RFC 8660: Segment Routing with the MPLS
Data Plane";
}
typedef system-id {
type string {
pattern
'[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}';
}
description
"This type defines IS-IS system-id using pattern,
An example system-id is 0143.0438.AEF0";
}
typedef router-or-system-id {
type union {
type rt-types:router-id;
type system-id;
}
description
"OSPF/BGP router-id or ISIS system ID.";
}
grouping sr-control-plane {
description
"Defines protocol configuration.";
container segment-routing {
description
"Segment Routing global configuration.";
leaf enabled {
type boolean;
default "false";
description
"Enables segment-routing control-plane protocol
extensions.";
}
container bindings {
if-feature mapping-server;
description
"Control of binding advertisement and reception.";
container advertise {
description
"Control advertisement of local mappings
in binding TLVs.";
leaf-list policies {
type leafref {
path "/rt:routing/sr:segment-routing/sr-mpls:sr-mpls"
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+ "/sr-mpls:bindings/sr-mpls:mapping-server"
+ "/sr-mpls:policy/sr-mpls:name";
}
description
"List of binding advertisement policies.";
}
}
leaf receive {
type boolean;
default "true";
description
"Allow the reception and usage of binding TLVs.";
}
}
}
}
grouping igp-interface {
description
"Grouping for IGP interface configuration.";
container segment-routing {
description
"Container for SR interface configuration.";
container adjacency-sid {
description
"Adjacency SID configuration.";
reference "RFC 8660: Segment Routing with the MPLS
Data Plane";
list adj-sids {
key "value";
uses sr-cmn:sid-value-type;
leaf value {
type uint32;
description
"Value of the Adj-SID.";
}
leaf protected {
type boolean;
default false;
description
"It is used to protect the manual adj-SID, e.g. using
IPFRR or MPLS-FRR.";
}
leaf weight {
type uint8;
description
"The load-balancing factor over parallel adjacencies.";
reference "RFC 8402: Segment Routing Architecture
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RFC 8665: OSPF Extensions for Segment Routing
RFC 8667: IS-IS Extensions for Segment
Routing";
}
description
"List of adj-sid configuration.";
}
list advertise-adj-group-sid {
key "group-id";
description
"Control advertisement of S or G flag. Enable
advertisement of a common Adj-SID for parallel
links.";
reference "RFC 8665: OSPF Extensions for Segment Routing
Section 6.1
RFC 8667: IS-IS Extensions for Segment
Routing Section 2.2.1";
leaf group-id {
type uint32;
description
"The value is an internal value to identify a
group-ID. Interfaces with the same group-ID
will be bundled together.";
}
}
leaf advertise-protection {
type enumeration {
enum "single" {
description
"A single Adj-SID is associated with the adjacency
and reflects the protection configuration.";
}
enum "dual" {
description
"Two Adj-SIDs will be associated with the adjacency
if the interface is protected. In this case, one
Adj-SID will be advertised with the backup-flag set
and the other with the backup-flag clear. In the
case where protection is not configured, a single
Adj-SID will be advertised with the backup-flag
clear.";
}
}
description
"If set, the Adj-SID refers to a protected adjacency.";
reference "RFC 8665: OSPF Extensions for Segment Routing
Section 6.1
RFC 8667: IS-IS Extensions for Segment
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Routing Section 2.2.1";
}
}
}
}
augment "/rt:routing/sr:segment-routing" {
description
"This augments routing data model (RFC 8349)
with Segment Routing (SR) with the MPLS Data Plane.";
container sr-mpls {
description
"Segment Routing global configuration and
operational state.";
container bindings {
description
"List of bindings.";
container mapping-server {
if-feature "mapping-server";
description
"Configuration of mapping-server local entries.";
list policy {
key "name";
description
"List mapping-server policies.";
leaf name {
type string;
description
"Name of the mapping policy.";
}
container entries {
description
"IPv4/IPv6 mapping entries.";
list mapping-entry {
key "prefix algorithm";
description
"Mapping entries.";
uses sr-cmn:prefix-sid;
}
}
}
}
container connected-prefix-sid-map {
description
"Prefix SID configuration.";
list connected-prefix-sid {
key "prefix algorithm";
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description
"List of prefix SID mapped to IPv4/IPv6
local prefixes.";
uses sr-cmn:prefix-sid;
uses sr-cmn:last-hop-behavior;
}
}
container local-prefix-sid {
description
"Local sid configuration.";
list local-prefix-sid {
key "prefix algorithm";
description
"List of local IPv4/IPv6 prefix-sids.";
uses sr-cmn:prefix-sid;
}
}
}
container srgb {
description
"Global SRGB configuration.";
uses sr-cmn:srgb;
}
container srlb {
description
"Segment Routing Local Block (SRLB) configuration.";
uses sr-cmn:srlb;
}
list label-blocks {
config false;
description
"List of label blocks currently in use.";
leaf lower-bound {
type uint32;
description
"Lower bound of the label block.";
}
leaf upper-bound {
type uint32;
description
"Upper bound of the label block.";
}
leaf size {
type uint32;
description
"Number of indexes in the block.";
}
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leaf free {
type uint32;
description
"Number of free indexes in the block.";
}
leaf used {
type uint32;
description
"Number of indexes in use in the block.";
}
leaf scope {
type enumeration {
enum "global" {
description
"Global SID.";
}
enum "local" {
description
"Local SID.";
}
}
description
"Scope of this label block.";
}
}
container sid-db {
config false;
description
"List of prefix and SID associations.";
list sid {
key "target sid source source-protocol binding-type";
ordered-by system;
description
"SID Binding.";
leaf target {
type string;
description
"Defines the target of the binding. It can be a
prefix or something else.";
}
leaf sid {
type uint32;
description
"Index associated with the prefix.";
}
leaf algorithm {
type uint8;
description
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"Algorithm to be used for the prefix SID.";
reference "RFC 8665: OSPF Extensions for Segment Routing
RFC 8667: IS-IS Extensions for Segment
Routing
RFC 8669: Segment Routing Prefix Segment
Identifier Extensions to BGP";
}
leaf source {
type inet:ip-address;
description
"IP address of the router that owns the binding.";
}
leaf used {
type boolean;
description
"Indicates if the binding is installed in the
forwarding plane.";
}
leaf source-protocol {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
description
"Routing protocol that owns the binding";
}
leaf binding-type {
type enumeration {
enum "prefix-sid" {
description
"Binding is learned from a prefix SID.";
}
enum "binding-tlv" {
description
"Binding is learned from a binding TLV.";
}
}
description
"Type of binding.";
}
leaf scope {
type enumeration {
enum "global" {
description
"Global SID.";
}
enum "local" {
description
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"Local SID.";
}
}
description
"SID scoping.";
}
}
}
}
}
notification segment-routing-srgb-collision {
description
"This notification is sent when SRGB blocks received from
routers collide.";
list srgb-collisions {
description
"List of SRGB blocks that collide.";
leaf lower-bound {
type uint32;
description
"Lower value in the block.";
}
leaf upper-bound {
type uint32;
description
"Upper value in the block.";
}
leaf routing-protocol {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
description
"Routing protocol reference for SRGB collision.";
}
leaf originating-rtr-id {
type router-or-system-id;
description
"Originating Router ID of this SRGB block.";
}
}
}
notification segment-routing-global-sid-collision {
description
"This notification is sent when a new mapping is learned
containing a mapping where the SID is already used.
The notification generation must be throttled with at least
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a 5 second gap between notifications.";
leaf received-target {
type string;
description
"Target received in the router advertisement that caused
the SID collision.";
}
leaf new-sid-rtr-id {
type router-or-system-id;
description
"Router ID that advertised the colliding SID.";
}
leaf original-target {
type string;
description
"Target already available in the database with the same SID
as the received target.";
}
leaf original-sid-rtr-id {
type router-or-system-id;
description
"Router-ID for the router that originally advertised the
conlliding SID, i.e., the instance in the database.";
}
leaf index {
type uint32;
description
"Value of the index used by two different prefixes.";
}
leaf routing-protocol {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
description
"Routing protocol reference for colliding SID.";
}
}
notification segment-routing-index-out-of-range {
description
"This notification is sent when a binding is received
containing a segment index which is out of the local
configured ranges. The notification generation must be
throttled with at least a 5 second gap between
notifications.";
leaf received-target {
type string;
description
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"A human-readable string representing the target
received in the protocol-specific advertisement
corresponding to the out-of-range index.";
}
leaf received-index {
type uint32;
description
"Value of the index received.";
}
leaf routing-protocol {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
description
"Routing protocol reference for out-of-range indexd.";
}
}
}
<CODE ENDS>
9. Security Considerations
The YANG modules specified in this document define a schema for data
that 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
[RFC8446].
The NETCONF access control model [RFC8341] provides the means to
restrict access for particular NETCONF or RESTCONF users to a pre-
configured subset of all available NETCONF or RESTCONF protocol
operations and content.
There are a number of data nodes defined in the modules that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. Writable data nodes represent
configuration of the router's bindings and the global and local label
blocks. These correspond to the following schema nodes:
/segment-routing
/segment-routing/mpls
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/segment-routing/mpls/bindings - Modification to the local
bindings could result in a Denial of Service (DoS) attack. An
attacker may also try to create segment conflicts (using the same
segment identifier for different purposes) to redirect traffic
within the trusted domain. However, the traffic will remain
within the trusted domain. Redirection could be used to route the
traffic to compromised nodes within the trusted domain or to avoid
certain security functions (e.g., firewall). Refer to section 8.1
of [RFC8402] for a discussion of the SR-MPLS trusted domain.
/segment-routing/mpls/srgb - Modification of the Segment Routing
Global Block (SRGB) could be used to mount a DoS attack. For
example, if the SRGB size is reduced to a very small value, a lot
of existing segments could no longer be installed leading to a
traffic disruption.
/segment-routing/mpls/srlb - Modification of the Segment Routing
Local Block (SRLB) could be used to mount a DoS attacks similar to
those applicable to the SRGB.
Some of the readable data nodes in the modules may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
notification) to these data nodes. The exposure of either the local
bindings or SID database would provide an attacker the segment
routing paths and related topology information. These correspond to
the following schema nodes:
/segment-routing/mpls/bindings - Knowledge of these data nodes can
be used to attack the local router with a Denial of Service (DoS)
attack.
/segment-routing/mpls/sid-db - Knowledge of these data nodes can
be used to attack the other routers in the segment routing domain
with either a a Denial of Service (DoS) attack or redirection
traffic destined for those routers.
Furthermore exposure the node's capabilities may be useful in
mounting a Denial-of-Service (DOS) attack by sending the node SR
packets that the router can't process. These correspond to the
following schema nodes:
/segment-routing/mpls/node-capabilities
/segment-routing/mpls/msd
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10. Acknowledgements
The authors would like to thank Derek Yeung, Greg Hankins, Hannes
Gredler, Uma Chunduri, Jeffrey Zhang, Shradda Hedge, Les Ginsberg for
their contributions.
Thanks to Ladislav Lhotka and Tom Petch for their thorough reviews
and helpful comments.
The authors would like to thank Benjamin Kaduk, Alvaro Retana, and
Roman Danyliw for IESG review and comments.
11. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688].
Following the format in [RFC3688], the following registration is
requested to be made:
URI: urn:ietf:params:xml:ns:yang:ietf-segment-routing-commmon
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-segment-routing
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-segment-routing-common
namespace: urn:ietf:params:xml:ns:yang:ietf-segment-routing-common
prefix: sr-cmn
reference: RFC XXXX
name: ietf-segment-routing
namespace: urn:ietf:params:xml:ns:yang:ietf-segment-routing
prefix: sr
reference: RFC XXXX
name: ietf-segment-routing-mpls
namespace: urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls
prefix: sr-mpls
reference: RFC XXXX
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12. References
12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[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>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[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>.
[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>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8294] Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger,
"Common YANG Data Types for the Routing Area", RFC 8294,
DOI 10.17487/RFC8294, December 2017,
<https://www.rfc-editor.org/info/rfc8294>.
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[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>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[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>.
[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>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476,
DOI 10.17487/RFC8476, December 2018,
<https://www.rfc-editor.org/info/rfc8476>.
[RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491,
DOI 10.17487/RFC8491, November 2018,
<https://www.rfc-editor.org/info/rfc8491>.
[RFC8660] Bashandy, A., Ed., Filsfils, C., Ed., Previdi, S.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing with the MPLS Data Plane", RFC 8660,
DOI 10.17487/RFC8660, December 2019,
<https://www.rfc-editor.org/info/rfc8660>.
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[RFC8665] Psenak, P., Ed., Previdi, S., Ed., Filsfils, C., Gredler,
H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", RFC 8665,
DOI 10.17487/RFC8665, December 2019,
<https://www.rfc-editor.org/info/rfc8665>.
[RFC8667] Previdi, S., Ed., Ginsberg, L., Ed., Filsfils, C.,
Bashandy, A., Gredler, H., and B. Decraene, "IS-IS
Extensions for Segment Routing", RFC 8667,
DOI 10.17487/RFC8667, December 2019,
<https://www.rfc-editor.org/info/rfc8667>.
[RFC8669] Previdi, S., Filsfils, C., Lindem, A., Ed., Sreekantiah,
A., and H. Gredler, "Segment Routing Prefix Segment
Identifier Extensions for BGP", RFC 8669,
DOI 10.17487/RFC8669, December 2019,
<https://www.rfc-editor.org/info/rfc8669>.
[RFC8814] Tantsura, J., Chunduri, U., Talaulikar, K., Mirsky, G.,
and N. Triantafillis, "Signaling Maximum SID Depth (MSD)
Using the Border Gateway Protocol - Link State", RFC 8814,
DOI 10.17487/RFC8814, August 2020,
<https://www.rfc-editor.org/info/rfc8814>.
12.2. Informative References
[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>.
[RFC8792] Watsen, K., Auerswald, E., Farrel, A., and Q. Wu,
"Handling Long Lines in Content of Internet-Drafts and
RFCs", RFC 8792, DOI 10.17487/RFC8792, June 2020,
<https://www.rfc-editor.org/info/rfc8792>.
Appendix A. Configuration examples
Note: '\' line wrapping per [RFC8792].
A.1. SR MPLS with IPv4
The following is an XML example using the SR MPLS YANG modules with
IPv4 addresses.
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<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<segment-routing
xmlns="urn:ietf:params:xml:ns:yang:ietf-segment-routing">
<sr-mpls
xmlns="urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls">
<bindings>
<mapping-server>
<policy>
<name>mapping 1</name>
<entries>
<mapping-entry>
<prefix>198.51.100.0/24</prefix>
<algorithm xmlns:sr-cmn="urn:ietf:params:xml:ns:yang\
:ietf-segment-routing-common">\
sr-cmn:prefix-sid-algorithm-shortest-path\
</algorithm>
<start-sid>200</start-sid>
<range>100</range>
</mapping-entry>
</entries>
</policy>
</mapping-server>
<connected-prefix-sid-map>
<connected-prefix-sid>
<prefix>192.0.2.0/24</prefix>
<algorithm xmlns:sr-cmn="urn:ietf:params:xml:ns:yang:\
ietf-segment-routing-common">\
sr-cmn:prefix-sid-algorithm-strict-spf</algorithm>
<start-sid>100</start-sid>
<range>1</range>
<last-hop-behavior>php</last-hop-behavior>
</connected-prefix-sid>
</connected-prefix-sid-map>
</bindings>
<srgb>
<srgb>
<lower-bound>45000</lower-bound>
<upper-bound>55000</upper-bound>
</srgb>
</srgb>
</sr-mpls>
</segment-routing>
</routing>
The following is the same example using JSON format.
{
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"ietf-routing:routing": {
"ietf-segment-routing:segment-routing": {
"ietf-segment-routing-mpls:sr-mpls": {
"bindings": {
"mapping-server": {
"policy": [
{
"name": "mapping 1",
"entries": {
"mapping-entry": [
{
"prefix": "198.51.100.0/24",
"algorithm": "ietf-segment-routing-common:\
prefix-sid-algorithm-shortest-path",
"start-sid": 200,
"range": 100
}
]
}
}
]
},
"connected-prefix-sid-map": {
"connected-prefix-sid": [
{
"prefix": "192.0.2.0/24",
"algorithm": "ietf-segment-routing-common:\
prefix-sid-algorithm-strict-spf",
"start-sid": 100,
"range": 1,
"last-hop-behavior": "php"
}
]
}
},
"srgb": {
"srgb": [
{
"lower-bound": 45000,
"upper-bound": 55000
}
]
}
}
}
}
}
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A.2. SR MPLS with IPv6
The following is an XML example using the SR MPLS YANG modules with
IPv6 addresses.
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<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<segment-routing
xmlns="urn:ietf:params:xml:ns:yang:ietf-segment-routing">
<sr-mpls
xmlns="urn:ietf:params:xml:ns:yang:ietf-segment-routing-mpls">
<bindings>
<mapping-server>
<policy>
<name>mapping 1</name>
<entries>
<mapping-entry>
<prefix>2001:db8:aaaa:bbbb::/64</prefix>
<algorithm xmlns:sr-cmn="urn:ietf:params:xml:ns:yang\
:ietf-segment-routing-common">\
sr-cmn:prefix-sid-algorithm-shortest-path\
</algorithm>
<start-sid>200</start-sid>
<range>100</range>
</mapping-entry>
</entries>
</policy>
</mapping-server>
<connected-prefix-sid-map>
<connected-prefix-sid>
<prefix>2001:db8:aaaa:cccc::/64</prefix>
<algorithm xmlns:sr-cmn="urn:ietf:params:xml:ns:yang:\
ietf-segment-routing-common">\
sr-cmn:prefix-sid-algorithm-strict-spf</algorithm>
<start-sid>100</start-sid>
<range>1</range>
<last-hop-behavior>php</last-hop-behavior>
</connected-prefix-sid>
</connected-prefix-sid-map>
</bindings>
<srgb>
<srgb>
<lower-bound>45000</lower-bound>
<upper-bound>55000</upper-bound>
</srgb>
</srgb>
</sr-mpls>
</segment-routing>
</routing>
The following is the same example using JSON format.
{
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"ietf-routing:routing": {
"ietf-segment-routing:segment-routing": {
"ietf-segment-routing-mpls:sr-mpls": {
"bindings": {
"mapping-server": {
"policy": [
{
"name": "mapping 1",
"entries": {
"mapping-entry": [
{
"prefix": "2001:db8:aaaa:bbbb::/64",
"algorithm": "ietf-segment-routing-common:\
prefix-sid-algorithm-shortest-path",
"start-sid": 200,
"range": 100
}
]
}
}
]
},
"connected-prefix-sid-map": {
"connected-prefix-sid": [
{
"prefix": "2001:db8:aaaa:cccc::/64",
"algorithm": "ietf-segment-routing-common:\
prefix-sid-algorithm-strict-spf",
"start-sid": 100,
"range": 1,
"last-hop-behavior": "php"
}
]
}
},
"srgb": {
"srgb": [
{
"lower-bound": 45000,
"upper-bound": 55000
}
]
}
}
}
}
}
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Authors' Addresses
Stephane Litkowski
Cisco Systems
Email: slitkows.ietf@gmail.com
Yingzhen Qu
Futurewei
Email: yingzhen.qu@futurewei.com
Acee Lindem
Cisco Systems
301 Mindenhall Way
Cary, NC 27513
US
Email: acee@cisco.com
Pushpasis Sarkar
Arrcus Networks
Email: pushpasis.ietf@gmail.com
Jeff Tantsura
Apstra
Email: jefftant.ietf@gmail.com
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