IS-IS Working Group S. Litkowski
Internet-Draft Cisco Systems
Intended status: Standards Track Y. Qu
Expires: February 17, 2022 Futurewei
P. Sarkar
Individual
I. Chen
The MITRE Corporation
J. Tantsura
Microsoft
August 16, 2021
YANG Data Model for IS-IS Segment Routing
draft-ietf-isis-sr-yang-11
Abstract
This document defines a YANG data module that can be used to
configure and manage IS-IS Segment Routing, as well as a YANG data
module for the management of Signaling Maximum SID Depth (MSD) Using
IS-IS.
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 February 17, 2022.
Copyright Notice
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
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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. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
2. IS-IS MSD . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. IS-IS MSD YANG Module . . . . . . . . . . . . . . . . . . 4
3. IS-IS Segment Routing . . . . . . . . . . . . . . . . . . . . 7
3.1. IS-IS Segment Routing configuration . . . . . . . . . . . 10
3.1.1. Segment Routing activation . . . . . . . . . . . . . 10
3.1.2. Advertising mapping server policy . . . . . . . . . . 10
3.1.3. IP Fast reroute . . . . . . . . . . . . . . . . . . . 11
3.2. IS-IS Segment Routing YANG Module . . . . . . . . . . . . 11
4. Security Considerations . . . . . . . . . . . . . . . . . . . 26
5. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 27
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 27
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27
8. Normative References . . . . . . . . . . . . . . . . . . . . 28
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29
1. Overview
YANG [RFC6020] [RFC7950] is a data definition language used to define
the contents of a conceptual data store that allows networked devices
to be managed using NETCONF [RFC6241]. YANG is proving relevant
beyond its initial confines, as bindings to other interfaces (e.g.,
ReST) and encodings other than XML (e.g., JSON) are being defined.
Furthermore, YANG data models can be used as the basis for
implementation of other interfaces, such as CLI and programmatic
APIs.
This document defines a YANG data module that can be used to
configure and manage IS-IS Segment Routing [RFC8667] and it is an
augmentation to the IS-IS YANG data model.
This document also defines a YANG data module for the management of
Signaling Maximum SID Depth (MSD) Using IS-IS [RFC8491], which
augments the base IS-IS YANG data model.
The YANG modules in this document conform to the Network Management
Datastore Architecture (NMDA) [RFC8342].
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1.1. Requirements Language
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.
1.2. Tree Diagrams
This document uses the graphical representation of data models
defined in [RFC8340].
2. IS-IS MSD
This document defines a model for Signaling Maximum SID Depth (MSD)
Using IS-IS[RFC8667]. It is an augmentation of the IS-IS base model.
The figure below describes the overall structure of the isis-msd YANG
module:
module: ietf-isis-msd
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:router-capabilities:
+--ro node-msd-tlv
+--ro node-msds* [msd-type]
+--ro msd-type identityref
+--ro msd-value? uint8
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:extended-is-neighbor
/isis:neighbor:
+--ro link-msd-sub-tlv
+--ro link-msds* [msd-type]
+--ro msd-type identityref
+--ro msd-value? uint8
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:mt-is-neighbor/isis:neighbor:
+--ro link-msd-sub-tlv
+--ro link-msds* [msd-type]
+--ro msd-type identityref
+--ro msd-value? uint8
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2.1. IS-IS MSD YANG Module
<CODE BEGINS> file "ietf-isis-msd@2021-08-15.yang"
module ietf-isis-msd {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-isis-msd";
prefix isis-msd;
import ietf-routing {
prefix rt;
reference "RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-isis {
prefix isis;
}
import ietf-mpls-msd {
prefix mpls-msd;
}
organization
"IETF LSR - LSR Working Group";
contact
"WG Web: <https://tools.ietf.org/wg/mpls/>
WG List: <mailto:mpls@ietf.org>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Stephane Litkowski
<mailto:slitkows.ietf@gmail.com>
Author: Jeff Tantsura
<mailto:jefftant.ietf@gmail.com>
";
description
"The YANG module augments the base ISIS model to
manage different types of MSDs.
This YANG model conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8342.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
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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 OSPF MSD.";
revision 2021-08-15 {
description
"Initial Version";
reference "RFC XXXX: YANG Data Model for ISIS MSD.";
}
grouping link-msd-sub-tlv {
description
"Link Maximum SID Depth (MSD) grouping for an interface.";
container link-msd-sub-tlv {
list link-msds {
key "msd-type";
leaf msd-type {
type identityref {
base mpls-msd:msd-base-type;
}
description
"MSD-Types";
}
leaf msd-value {
type uint8;
description
"MSD value, in the range of 0-255.";
}
description
"List of link MSDs";
}
description
"Link MSD sub-tlvs.";
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}
}
/* Node MSD TLV */
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:router-capabilities" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB router capability.";
container node-msd-tlv {
list node-msds {
key "msd-type";
leaf msd-type {
type identityref {
base mpls-msd:msd-base-type;
}
description
"MSD-Types";
}
leaf msd-value {
type uint8;
description
"MSD value, in the range of 0-255.";
}
description
"Node MSD is the smallest link MSD supported by
the node.";
}
description
"Node MSD is the number of SIDs supported by a node.";
reference
"RFC 8476: Signaling Maximum SID Depth (MSD) Using OSPF";
}
}
/* link MSD sub-tlv */
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:extended-is-neighbor/isis:neighbor" {
when "/rt:routing/rt:control-plane-protocols/"+
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"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB neighbor with
Link MSD sub-TLV.";
uses link-msd-sub-tlv;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:mt-is-neighbor/isis:neighbor" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB neighbor.";
uses link-msd-sub-tlv;
}
}
<CODE ENDS>
3. IS-IS Segment Routing
This document defines a model for IS-IS Segment Routing feature. It
is an augmentation of the IS-IS base model.
The IS-IS SR YANG module requires support for the base segment
routing module [I-D.ietf-spring-sr-yang], which defines the global
segment routing configuration independent of any specific routing
protocol configuration, and support of IS-IS base model
[I-D.ietf-isis-yang-isis-cfg] which defines basic IS-IS configuration
and state.
The figure below describes the overall structure of the isis-sr YANG
module:
module: ietf-isis-sr
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis:
+--rw segment-routing
| +--rw enabled? boolean
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| +--rw bindings
| +--rw advertise
| | +--rw policies* string
| +--rw receive? boolean
+--rw protocol-srgb {sr-mpls:protocol-srgb}?
+--rw srgb* [lower-bound upper-bound]
+--rw lower-bound uint32
+--rw upper-bound uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:interfaces
/isis:interface:
+--rw segment-routing
+--rw adjacency-sid
+--rw adj-sids* [value]
| +--rw value-type? enumeration
| +--rw value uint32
| +--rw protected? boolean
+--rw advertise-adj-group-sid* [group-id]
| +--rw group-id uint32
+--rw advertise-protection? enumeration
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:interfaces
/isis:interface/isis:fast-reroute:
+--rw ti-lfa {ti-lfa}?
+--rw enable? boolean
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:interfaces
/isis:interface/isis:fast-reroute/isis:lfa/isis:remote-lfa:
+--rw use-segment-routing-path? boolean {remote-lfa-sr}?
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:interfaces
/isis:interface/isis:adjacencies/isis:adjacency:
+--ro adjacency-sid* [value]
+--ro af? iana-rt-types:address-family
+--ro value uint32
+--ro weight? uint8
+--ro protection-requested? boolean
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:router-capabilities:
+--ro sr-capability
| +--ro sr-capability
| | +--ro sr-capability-bits* identityref
| +--ro global-blocks
| +--ro global-block* []
| +--ro range-size? uint32
| +--ro sid-sub-tlv
| +--ro sid? uint32
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+--ro sr-algorithms
| +--ro sr-algorithm* uint8
+--ro local-blocks
| +--ro local-block* []
| +--ro range-size? uint32
| +--ro sid-sub-tlv
| +--ro sid? uint32
+--ro srms-preference
+--ro preference? uint8
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database/isis:levels
/isis:lsp/isis:extended-is-neighbor/isis:neighbor:
+--ro sid-list* [value]
+--ro adj-sid-flags
| +--ro bits* identityref
+--ro weight? uint8
+--ro neighbor-id? isis:system-id
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:mt-is-neighbor/isis:neighbor:
+--ro sid-list* [value]
+--ro adj-sid-flags
| +--ro bits* identityref
+--ro weight? uint8
+--ro neighbor-id? isis:system-id
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:extended-ipv4-reachability
/isis:prefixes:
+--ro sid-list* [value]
+--ro perfix-sid-flags
| +--ro bits* identityref
+--ro algorithm? uint8
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:mt-extended-ipv4-reachability
/isis:prefixes:
+--ro sid-list* [value]
+--ro perfix-sid-flags
| +--ro bits* identityref
+--ro algorithm? uint8
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:ipv6-reachability/isis:prefixes:
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+--ro sid-list* [value]
+--ro perfix-sid-flags
| +--ro bits* identityref
+--ro algorithm? uint8
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp/isis:mt-ipv6-reachability/isis:prefixes:
+--ro sid-list* [value]
+--ro perfix-sid-flags
| +--ro bits* identityref
+--ro algorithm? uint8
+--ro value uint32
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/isis:isis/isis:database
/isis:levels/isis:lsp:
+--ro segment-routing-bindings* [fec range]
+--ro fec string
+--ro range uint16
+--ro sid-binding-flags
| +--ro bits* identityref
+--ro binding
+--ro prefix-sid
+--ro sid-list* [value]
+--ro perfix-sid-flags
| +--ro bits* identityref
+--ro algorithm? uint8
+--ro value uint32
3.1. IS-IS Segment Routing configuration
3.1.1. Segment Routing activation
Activation of segment-routing IS-IS is done by setting the "enable"
leaf to true. This triggers advertisement of segment-routing
extensions based on the configuration parameters that have been setup
using the base segment routing module.
3.1.2. Advertising mapping server policy
The base segment routing module defines mapping server policies. By
default, IS-IS will not advertise nor receive any mapping server
entry. The IS-IS segment-routing module allows to advertise one or
multiple mapping server policies through the "bindings/advertise/
policies" leaf-list. The "bindings/receive" leaf allows to enable
the reception of mapping server entries.
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3.1.3. IP Fast reroute
IS-IS SR model augments the fast-reroute container under interface.
It brings the ability to activate TI-LFA (topology independent LFA)
and also enhances remote LFA to use segment-routing tunneling instead
of LDP.
3.2. IS-IS Segment Routing YANG Module
<CODE BEGINS> file "ietf-isis-sr@2021-01-11.yang"
module ietf-isis-sr {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:"
+ "yang:ietf-isis-sr";
prefix isis-sr;
import ietf-routing {
prefix "rt";
reference "RFC 8349 - A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-segment-routing-common {
prefix "sr-cmn";
}
import ietf-segment-routing-mpls {
prefix "sr-mpls";
}
import ietf-isis {
prefix "isis";
}
import iana-routing-types {
prefix "iana-rt-types";
reference "RFC 8294 - Common YANG Data Types for the
Routing Area";
}
organization
"IETF LSR - LSR Working Group";
contact
"WG List: <mailto:lsr@ietf.org>
Editor: Stephane Litkowski
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<mailto:stephane.litkowski@orange.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>
Author: Pushpasis Sarkar
<mailto:pushpasis.ietf@gmail.com>
Author: Ing-Wher Chen
<mailto:ingwherchen@mitre.org>
Author: Jeff Tantsura
<mailto:jefftant.ietf@gmail.com>
";
description
"The YANG module defines a generic configuration model for
Segment routing ISIS extensions common across all of the vendor
implementations.
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
(https://www.rfc-editor.org/info/rfcXXXX); 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.
This version of this YANG module is part of RFC XXXX;
see the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2021-01-11 {
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description
"Initial revision.";
reference "RFC XXXX";
}
/* Identities */
identity sr-capability {
description
"Base identity for ISIS SR-Capabilities sub-TLV flgs";
}
identity mpls-ipv4 {
base sr-capability;
description
"If set, then the router is capable of
processing SR MPLS encapsulated IPv4 packets
on all interfaces.";
}
identity mpls-ipv6 {
base sr-capability;
description
"If set, then the router is capable of
processing SR MPLS encapsulated IPv6 packets
on all interfaces.";
}
identity prefix-sid-bit {
description
"Base identity for prefix sid sub-tlv bits.";
}
identity r-bit {
base prefix-sid-bit;
description
"Re-advertisement Flag.";
}
identity n-bit {
base prefix-sid-bit;
description
"Node-SID Flag.";
}
identity p-bit {
base prefix-sid-bit;
description
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"No-PHP (No Penultimate Hop-Popping) Flag.";
}
identity e-bit {
base prefix-sid-bit;
description
"Explicit NULL Flag.";
}
identity v-bit {
base prefix-sid-bit;
description
"Value Flag.";
}
identity l-bit {
base prefix-sid-bit;
description
"Local Flag.";
}
identity adj-sid-bit {
description
"Base identity for adj sid sub-tlv bits.";
}
identity f-bit {
base adj-sid-bit;
description
"Address-Family flag.";
}
identity b-bit {
base adj-sid-bit;
description
"Backup flag.";
}
identity vi-bit {
base adj-sid-bit;
description
"Value/Index flag.";
}
identity lo-bit {
base adj-sid-bit;
description
"Local flag.";
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}
identity s-bit {
base adj-sid-bit;
description
"Group flag.";
}
identity pe-bit {
base adj-sid-bit;
description
"Persistent flag.";
}
identity sid-binding-bit {
description
"Base identity for sid binding tlv bits.";
}
identity af-bit {
base sid-binding-bit;
description
"Address-Family flag.";
}
identity m-bit {
base sid-binding-bit;
description
"Mirror Context flag.";
}
identity sf-bit {
base sid-binding-bit;
description
"S flag. If set, the binding label tlv should be flooded
across the entire routing domain.";
}
identity d-bit {
base sid-binding-bit;
description
"Leaking flag.";
}
identity a-bit {
base sid-binding-bit;
description
"Attached flag.";
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}
/* Features */
feature remote-lfa-sr {
description
"Enhance rLFA to use SR path.";
}
feature ti-lfa {
description
"Enhance IPFRR with ti-lfa
support";
}
/* Groupings */
grouping sid-sub-tlv {
description "SID/Label sub-TLV grouping.";
container sid-sub-tlv {
description
"Used to advertise the SID/Label associated with a
prefix or adjacency.";
leaf sid {
type uint32;
description
"Segment Identifier (SID) - A 20 bit label or
32 bit SID.";
}
}
}
grouping sr-capability {
description
"SR capability grouping.";
container sr-capability {
description
"Segment Routing capability.";
container sr-capability {
leaf-list sr-capability-bits {
type identityref {
base sr-capability;
}
description "SR Capbility sub-tlv flags list.";
}
description
"SR Capability Flags.";
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}
container global-blocks {
description
"Segment Routing Global Blocks.";
list global-block {
description "Segment Routing Global Block.";
leaf range-size {
type uint32;
description "The SID range.";
}
uses sid-sub-tlv;
}
}
}
}
grouping sr-algorithm {
description
"SR algorithm grouping.";
container sr-algorithms {
description "All SR algorithms.";
leaf-list sr-algorithm {
type uint8;
description
"The Segment Routing (SR) algorithms that the router is
currently using.";
}
}
}
grouping srlb {
description
"SR Local Block grouping.";
container local-blocks {
description "List of SRLBs.";
list local-block {
description "Segment Routing Local Block.";
leaf range-size {
type uint32;
description "The SID range.";
}
uses sid-sub-tlv;
}
}
}
grouping srms-preference {
description "The SRMS preference TLV is used to advertise
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a preference associated with the node that acts
as an SR Mapping Server.";
container srms-preference {
description "SRMS Preference TLV.";
leaf preference {
type uint8 {
range "0 .. 255";
}
description "SRMS preference TLV, vlaue from 0 to 255.";
}
}
}
grouping adjacency-state {
description
"This group will extend adjacency state.";
list adjacency-sid {
key value;
config false;
leaf af {
type iana-rt-types:address-family;
description
"Address-family associated with the
segment ID";
}
leaf value {
type uint32;
description
"Value of the Adj-SID.";
}
leaf weight {
type uint8;
description
"Weight associated with
the adjacency SID.";
}
leaf protection-requested {
type boolean;
description
"Describe if the adjacency SID
must be protected.";
}
description
"List of adjacency Segment IDs.";
}
}
grouping prefix-segment-id {
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description
"This group defines segment routing extensions
for prefixes.";
list sid-list {
key value;
container perfix-sid-flags {
leaf-list bits {
type identityref {
base prefix-sid-bit;
}
description
"Prefix SID Sub-TLV flag bits list.";
}
description
"Describes flags associated with the
segment ID.";
}
leaf algorithm {
type uint8;
description
"Algorithm to be used for path computation.";
}
leaf value {
type uint32;
description
"Value of the prefix-SID.";
}
description
"List of segments.";
}
}
grouping adjacency-segment-id {
description
"This group defines segment routing extensions
for adjacencies.";
list sid-list {
key value;
container adj-sid-flags {
leaf-list bits {
type identityref {
base adj-sid-bit;
}
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description "Adj sid sub-tlv flags list.";
}
description "Adj-sid sub-tlv flags.";
}
leaf weight {
type uint8;
description
"The value represents the weight of the Adj-SID
for the purpose of load balancing.";
}
leaf neighbor-id {
type isis:system-id;
description
"Describes the system ID of the neighbor
associated with the SID value. This is only
used on LAN adjacencies.";
}
leaf value {
type uint32;
description
"Value of the Adj-SID.";
}
description
"List of segments.";
}
}
grouping segment-routing-binding-tlv {
list segment-routing-bindings {
key "fec range";
leaf fec {
type string;
description
"IP (v4 or v6) range to be bound to SIDs.";
}
leaf range {
type uint16;
description
"Describes number of elements to assign
a binding to.";
}
container sid-binding-flags {
leaf-list bits {
type identityref {
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base sid-binding-bit;
}
description
"SID Binding TLV flag bits list.";
}
description
"Binding flags.";
}
container binding {
container prefix-sid {
uses prefix-segment-id;
description
"Binding prefix SID to the range.";
}
description
"Bindings associated with the range.";
}
description
"This container describes list of SID/Label bindings.
ISIS reference is TLV 149.";
}
description
"Defines binding TLV for database.";
}
/* Cfg */
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol configuration
with segment routing.";
uses sr-mpls:sr-control-plane;
container protocol-srgb {
if-feature sr-mpls:protocol-srgb;
uses sr-cmn:srgb;
description
"Per-protocol SRGB.";
}
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}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:interfaces/isis:interface" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol configuration
with segment routing.";
uses sr-mpls:igp-interface;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:interfaces/isis:interface"+
"/isis:fast-reroute" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS IP FRR with TILFA.";
container ti-lfa {
if-feature ti-lfa;
leaf enable {
type boolean;
description
"Enables TI-LFA computation.";
}
description
"TILFA configuration.";
}
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:interfaces/isis:interface"+
"/isis:fast-reroute/isis:lfa/isis:remote-lfa" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
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"This augment ISIS routing protocol when used";
}
description
"This augments ISIS remoteLFA config with
use of segment-routing path.";
leaf use-segment-routing-path {
if-feature remote-lfa-sr;
type boolean;
description
"force remote LFA to use segment routing
path instead of LDP path.";
}
}
/* Operational states */
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:interfaces/isis:interface" +
"/isis:adjacencies/isis:adjacency" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol configuration
with segment routing.";
uses adjacency-state;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:router-capabilities" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB router capability.";
uses sr-capability;
uses sr-algorithm;
uses srlb;
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uses srms-preference;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:extended-is-neighbor/isis:neighbor" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB neighbor.";
uses adjacency-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:mt-is-neighbor/isis:neighbor" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB neighbor.";
uses adjacency-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:extended-ipv4-reachability/isis:prefixes" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB prefix.";
uses prefix-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
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"/isis:mt-extended-ipv4-reachability/isis:prefixes" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB prefix.";
uses prefix-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:ipv6-reachability/isis:prefixes" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB prefix.";
uses prefix-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp"+
"/isis:mt-ipv6-reachability/isis:prefixes" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
"This augments ISIS protocol LSDB prefix.";
uses prefix-segment-id;
}
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:database/isis:levels/isis:lsp" {
when "/rt:routing/rt:control-plane-protocols/"+
"rt:control-plane-protocol/rt:type = 'isis:isis'" {
description
"This augment ISIS routing protocol when used";
}
description
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"This augments ISIS protocol LSDB.";
uses segment-routing-binding-tlv;
}
/* Notifications */
}
<CODE ENDS>
4. Security Considerations
The YANG module specified in this document defines 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 (NACM) [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 this YANG module 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:
/isis:isis/segment-routing
/isis:isis/protocol-srgb
/isis:isis/isis:interfaces/isis:interface/segment-routing
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.
/isis:router-capabilities/sr-capability
/isis:router-capabilities/sr-algorithms
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/isis:router-capabilities/local-blocks
/isis:router-capabilities/srms-preference
/isis:router-capabilities/node-msd-tlv
And the augmentations to the ISIS link state database.
Unauthorized access to any data node of these subtrees can disclose
the operational state information of IS-IS protocol on this device.
5. Contributors
Authors would like to thank Derek Yeung, Acee Lindem, Yi Yang for
their major contributions to the draft.
6. Acknowledgements
MITRE has approved this document for Public Release, Distribution
Unlimited, with Public Release Case Number 19-3033.
7. IANA Considerations
The IANA is requested to assign two new URIs from the IETF XML
registry ([RFC3688]). Authors are suggesting the following URI:
URI: urn:ietf:params:xml:ns:yang:ietf-isis-sr
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace
URI: urn:ietf:params:xml:ns:yang:ietf-isis-msd
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace
This document also requests one new YANG module name in the YANG
Module Names registry ([RFC6020]) with the following suggestion :
name: ietf-isis-sr
namespace: urn:ietf:params:xml:ns:yang:ietf-isis-sr
prefix: isis-sr
reference: RFC XXXX
name: ietf-isis-msd
namespace: urn:ietf:params:xml:ns:yang:ietf-isis-msd
prefix: isis-msd
reference: RFC XXXX
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8. Normative References
[I-D.ietf-isis-yang-isis-cfg]
Litkowski, S., Yeung, D., Lindem, A., Zhang, J., and L.
Lhotka, "YANG Data Model for IS-IS Protocol", draft-ietf-
isis-yang-isis-cfg-42 (work in progress), October 2019.
[I-D.ietf-spring-sr-yang]
Litkowski, S., Qu, Y., Sarkar, P., and J. Tantsura, "YANG
Data Model for Segment Routing", draft-ietf-spring-sr-
yang-15 (work in progress), December 2017.
[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>.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536,
DOI 10.17487/RFC6536, March 2012,
<https://www.rfc-editor.org/info/rfc6536>.
[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>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[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>.
[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>.
[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>.
[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>.
[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>.
Authors' Addresses
Stephane Litkowski
Cisco Systems
Email: slitkows.ietf@gmail.com
Yinghzen Qu
Futurewei
Email: yingzhen.qu@futurewei.com
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Pushpasis Sarkar
Individual
Email: pushpasis.ietf@gmail.com
Ing-Wher Chen
The MITRE Corporation
Email: ingwherchen@mitre.org
Jeff Tantsura
Microsoft
Email: jefftant.ietf@gmail.com
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