| RFC 9020 | SR YANG Data Model | May 2021 |
| Litkowski, et al. | Standards Track | [Page] |
This document defines three YANG data models. The first is for Segment Routing (SR) configuration and operation, which is to be augmented by different Segment Routing data planes. The next is a YANG data model that defines a collection of generic types and groupings for SR. The third module defines the configuration and operational states for the Segment Routing MPLS data plane.¶
This is an Internet Standards Track document.¶
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.¶
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9020.¶
Copyright (c) 2021 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.¶
This document defines three YANG data models [RFC7950]. The first one is for Segment Routing (SR) [RFC8402] configuration and operation. This document does not define the IGP extensions to support SR, but the second module defines generic groupings to be reused by IGP extension modules. The reason for 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 third YANG data model defines a module that is intended to be used on network elements to configure or operate the SR MPLS data plane [RFC8660].¶
The YANG modules in this document conform to the Network Management Datastore Architecture (NMDA) [RFC8342].¶
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.¶
Tree diagrams used in this document follow the notation defined in [RFC8340].¶
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.¶
The ietf-segment-routing YANG module augments the routing container in the ietf-routing model [RFC8349] and defines generic SR configuration and operational state. This module is augmented by modules supporting different data planes.¶
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* []
| +--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
¶
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 SR MPLS data plane.¶
The sr-mpls configuration is split into global configuration and interface configuration.¶
The global configuration includes:¶
Defines Prefix to Segment Identifier (Prefix-SID) mappings. The operator can control advertisement of Prefix-SIDs independently for IPv4 and IPv6. Two types of mappings are available:¶
Support of SR extensions for a particular IGP control plane is achieved by augmenting routing-protocol configuration with SR extensions. This augmentation SHOULD be part of the routing-protocol YANG modules as not to create any dependency for implementations to support SR extensions for all routing protocols.¶
This module defines groupings that SHOULD be used by IGP SR modules.¶
The "sr-control-plane" grouping defines the generic global configuration for the IGP.¶
The "enabled" leaf enables SR 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.¶
The interface configuration is part of the "igp-interface" grouping and includes Adjacency SID (Adj-SID) properties.¶
In case of parallel IP links between routers, an additional Adj-SID [RFC8402] may be advertised representing more than one adjacency (i.e., a bundle of adjacencies). The "advertise-adj-group-sid" configuration controls for which group(s) an additional Adj-SID is advertised.¶
The "advertise-adj-group-sid" is a list of group IDs. Each 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. The operator would like to create Adj-SIDs that represent bundles of links. We can imagine two different bundles: L1/L2 and L3/L4. To achieve this behavior, the operator will configure a "group-id" X for interfaces L1 and L2 and a "group-id" Y for interfaces L3 and L4. This will result in R1 advertising an additional Adj-SID for each adjacency. For example, an Adj-SID with a value of 400 will be added to L1 and L2, and an Adj-SID with a value of 500 will be added to L3 and L4. As L1/L2 and L3/L4 do not share the same "group-id", a different SID value will be allocated.¶
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 unprotected segments.¶
The operational state contains 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 associated source protocol and algorithm.¶
The model defines the following notifications for SR.¶
There are three YANG modules included in this document.¶
The following RFCs 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], [RFC8661], [RFC8665], [RFC8667], [RFC8669], and [RFC8814].¶
<CODE BEGINS> file "ietf-segment-routing@2021-04-01.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://datatracker.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
"This YANG module defines a generic framework for Segment
Routing (SR). It is to be augmented by models for different
SR data planes.
This YANG module conforms to the Network Management
Datastore Architecture (NMDA), as described in RFC 8242.
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.
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 9020;
see the RFC itself for full legal notices.";
reference
"RFC 9020: YANG Data Model for Segment Routing.";
revision 2021-04-01 {
description
"Initial version";
reference
"RFC 9020: YANG Data Model for Segment Routing.";
}
augment "/rt:routing" {
description
"This module augments the 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>¶
<CODE BEGINS> file "ietf-segment-routing-common@2021-04-01.yang"
module ietf-segment-routing-common {
yang-version 1.1;
namespace
"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://datatracker.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
"This YANG module defines a collection of generic types and
groupings for Segment Routing (SR), as described in RFC 8402.
This YANG module conforms to the Network Management
Datastore Architecture (NMDA), as described in RFC 8242.
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.
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 9020;
see the RFC itself for full legal notices.";
reference
"RFC 9020: YANG Data Model for Segment Routing";
revision 2021-04-01 {
description
"Initial version";
reference
"RFC 9020: 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 the 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 {
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
value.";
}
}
default "index";
description
"This leaf defines how the value must be interpreted.";
}
}
grouping prefix-sid {
description
"This grouping defines configuration of a 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 {
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 sid-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>¶
<CODE BEGINS> file "ietf-segment-routing-mpls@2021-04-01.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 9020: YANG Data Model for Segment Routing";
}
import ietf-segment-routing-common {
prefix sr-cmn;
reference
"RFC 9020: YANG Data Model for Segment Routing";
}
organization
"IETF SPRING - SPRING Working Group";
contact
"WG Web: <https://datatracker.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
"This YANG module defines a generic configuration model for
the Segment Routing MPLS data plane.
This YANG module conforms to the Network Management
Datastore Architecture (NMDA), as described in RFC 8242.
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.
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 9020;
see the RFC itself for full legal notices.";
reference
"RFC 9020: YANG Data Model for Segment Routing";
revision 2021-04-01 {
description
"Initial version";
reference
"RFC 9020: 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
(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 an IS-IS system-id using a 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 IS-IS 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"
+ "/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 (Adj-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 Adj-SID, e.g., using
IP Fast Reroute (IPFRR) or MPLS-FRR.";
}
leaf weight {
type uint8;
description
"The load-balancing factor over parallel adjacencies.";
reference
"RFC 8402: Segment Routing Architecture
RFC 8665: OSPF Extensions for Segment Routing
RFC 8667: IS-IS Extensions for Segment
Routing";
}
description
"List of Adj-SIDs and their configuration.";
}
list advertise-adj-group-sid {
key "group-id";
description
"Control advertisement of S-flag 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
Routing, Section 2.2.1";
}
}
}
}
augment "/rt:routing/sr:segment-routing" {
description
"This augments the routing data model (RFC 8349)
with Segment Routing (SR) using 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";
description
"List of mappings of Prefix-SIDs 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.";
}
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
"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
"Local SID.";
}
}
description
"SID scoping.";
}
}
}
}
}
notification segment-routing-srgb-collision {
description
"This notification is sent when SRGB blocks received from
different 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
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
colliding 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 that 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
"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 indexed.";
}
}
}
<CODE ENDS>¶
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 Network Configuration Access Control Model (NACM) [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.¶
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. These are the subtrees and data nodes and their sensitivity/vulnerability:¶
Some of the readable data nodes in these YANG 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. These are the subtrees and data nodes and their sensitivity/vulnerability:¶
This document registers a URI in the "IETF XML Registry" [RFC3688]. Following the format in [RFC3688], the following registration is requested to be made:¶
This document registers YANG modules in the "YANG Module Names" registry [RFC6020].¶
Note: '\' line wrapping per [RFC8792].¶
The following is an XML [W3C.REC-xml11-20060816] example using the SR-MPLS YANG modules with IPv4 addresses.¶
<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.¶
{
"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
}
]
}
}
}
}
}
¶
The following is an XML [W3C.REC-xml11-20060816] example using the SR-MPLS YANG modules with IPv6 addresses.¶
<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.¶
{
"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
}
]
}
}
}
}
}
¶
The authors would like to thank Derek Yeung, Greg Hankins, Hannes Gredler, Uma Chunduri, Jeffrey Zhang, Shradda Hedge, and 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.¶