RFC 9130
YANG Data Model for the IS-IS Protocol
RFC 9130: YANG Data Model for the IS-IS Protocol 🎀
Okay bestie, let's start with the basics 💅. This is RFC 9130, a Standards Track document, so it's the real deal and not just a vibe. It came out in October 2022 and is part of the ISSN 2070-1721 series. The editor is S. Litkowski (Ed.) from Cisco Systems, and the other authors are D. Yeung from Arrcus, Inc., A. Lindem from Cisco Systems, J. Zhang from Juniper Networks, and L. Lhotka from CZ.NIC. The title block doesn't list anything it obsoletes or updates, so there's no drama there ✨.
Abstract 💜
Okay so the abstract is short and sweet: this doc defines a YANG data model that you can use to configure and manage the IS-IS protocol on network elements 🧚.
Status of This Memo 📜
This is an Internet Standards Track document 🌈.
It's a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community, it got public review, and the Internet Engineering Steering Group (IESG) approved it for publication. For more on Internet Standards, check out Section 2 of RFC 7841 🙈.
If you want the latest on this doc's status, any errata, or how to send feedback, go to https://www.rfc-editor.org/info/rfc9130 🔗.
Copyright Notice ©️
Copyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved 💖.
This doc is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) as they stand on the publication date. Please read these carefully, bestie, because they spell out your rights and restrictions for this document. Code Components pulled out of this document must include the Revised BSD License text described in Section 4.e of the Trust Legal Provisions, and they come without warranty, as the Revised BSD License describes 🫶.
Table of Contents 🗂️
1. Introduction
1.1. Requirements Language
2. Design of the Data Model
2.1. IS-IS Configuration
2.2. Multi-Topology Parameters
2.3. Per-Level Parameters
2.4. Per-Interface Parameters
2.5. Authentication Parameters
2.6. IGP/LDP Synchronization
2.7. ISO Parameters
2.8. IP FRR
2.9. Operational States
3. RPC Operations
4. Notifications
5. Interactions with Other YANG Modules
6. IS-IS YANG Module
7. Security Considerations
8. IANA Considerations
9. References
9.1. Normative References
9.2. Informative References
Appendix A. Example of IS-IS Configuration in XML
Acknowledgments
Contributors
Authors' Addresses1. Introduction ✨
This doc defines a YANG data model [RFC7950] for the IS-IS routing protocol 🦋.
The data model covers configuring an IS-IS routing protocol instance, and it also covers retrieving IS-IS operational states 💅.
A simplified tree representation of the data model shows up in Section 2. The tree diagrams in this doc follow the notation defined in [RFC8340] 🌸.
The module in this doc is designed according to the Network Management Datastore Architecture (NMDA) [RFC8342] 👑.
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 doc are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here 🧠.
2. Design of the Data Model 🍓
The IS-IS YANG module augments the "control-plane-protocol" list in the "ietf-routing" module [RFC8349] with specific IS-IS parameters 💜.
Here's the diagram showing the overall structure of the "ietf-isis" YANG module defined in this doc. Heads up: the '' line wrapping follows [RFC8792] 🙈.
module: ietf-isis
augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route:
+--ro metric? uint32
+--ro tag* uint64
+--ro route-type? enumeration
augment /if:interfaces/if:interface:
+--rw clns-mtu? uint16 {osi-interface}?
augment /rt:routing/rt:control-plane-protocols/rt:
control-plane-protocol:
+--rw isis
+--rw enabled? boolean {admin-control}?
+--rw level-type? level
+--rw system-id? system-id
+--rw maximum-area-addresses? \
uint8 {maximum-area-addresses}?
+--rw area-address* area-address
+--rw lsp-mtu? uint16
+--rw lsp-lifetime? uint16
+--rw lsp-refresh? rt-types:timer-value-seconds16
| {lsp-refresh}?
+--rw poi-tlv? boolean {poi-tlv}?
+--rw graceful-restart {graceful-restart}?
| +--rw enabled? boolean
| +--rw restart-interval? rt-types:timer-value-seconds16
| +--rw helper-enabled? boolean
+--rw nsr {nsr}?
| +--rw enabled? boolean
+--rw node-tags {node-tag}?
| +--rw node-tag* [tag]
| ...
+--rw metric-type
| +--rw value? enumeration
| +--rw level-1
| | ...
| +--rw level-2
| ...
+--rw default-metric
| +--rw value? wide-metric
| +--rw level-1
| | ...
| +--rw level-2
| ...
+--rw auto-cost {auto-cost}?
| +--rw enabled? boolean
| +--rw reference-bandwidth? uint32
+--rw authentication
| +--rw (authentication-type)?
| | ...
| +--rw level-1
| | ...
| +--rw level-2
| ...
+--rw address-families {nlpid-control}?
| +--rw address-family-list* [address-family]
| ...
+--rw mpls
| +--rw te-rid {te-rid}?
| | ...
| +--rw ldp
| ...
+--rw spf-control
| +--rw paths? uint16 {max-ecmp}?
| +--rw ietf-spf-delay {ietf-spf-delay}?
| ...
+--rw fast-reroute {fast-reroute}?
| +--rw lfa {lfa}?
+--rw preference
| +--rw (granularity)?
| ...
+--rw overload
| +--rw status? boolean
+--rw overload-max-metric {overload-max-metric}?
| +--rw timeout? rt-types:timer-value-seconds16
+--ro spf-log
| +--ro event* [id]
| ...
+--ro lsp-log
| +--ro event* [id]
| ...
+--ro hostnames
| +--ro hostname* [system-id]
| ...
+--ro database
| +--ro levels* [level]
| ...
+--ro local-rib
| +--ro route* [prefix]
| ...
+--ro system-counters
| +--ro level* [level]
| ...
+--ro protected-routes
| +--ro address-family-stats* \
| [address-family prefix alternate]
| ...
+--ro unprotected-routes
| +--ro prefixes* [address-family prefix]
| ...
+--ro protection-statistics* [frr-protection-method]
| +--ro frr-protection-method identityref
| +--ro address-family-stats* [address-family]
| ...
+--rw discontinuity-time? yang:date-and-time
+--rw topologies {multi-topology}?
| +--rw topology* [name]
| ...
+--rw interfaces
+--rw interface* [name]
...
rpcs:
+---x clear-adjacency
| +---w input
| +---w routing-protocol-instance-name -> /rt:routing/
| | control-plane-\
| | protocols/
| | control-plane-\
| | protocol/name
| +---w level? level
| +---w interface? if:interface-ref
+---x clear-database
+---w input
+---w routing-protocol-instance-name -> /rt:routing/
| control-plane-\
| protocols/
| control-plane-\
| protocol/name
+---w level? level notifications:
+---n database-overload
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro overload? enumeration
+---n lsp-too-large
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro pdu-size? uint32
| +--ro lsp-id? lsp-id
+---n if-state-change
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro state? if-state-type
+---n corrupted-lsp-detected
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro lsp-id? lsp-id
+---n attempt-to-exceed-max-sequence
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro lsp-id? lsp-id
+---n id-len-mismatch
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro pdu-field-len? uint8
| +--ro raw-pdu? binary
+---n max-area-addresses-mismatch
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro max-area-addresses? uint8
| +--ro raw-pdu? binary
+---n own-lsp-purge
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro lsp-id? lsp-id
+---n sequence-number-skipped
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro lsp-id? lsp-id
+---n authentication-type-failure
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro raw-pdu? binary
+---n authentication-failure
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro raw-pdu? binary
+---n version-skew
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro protocol-version? uint8
| +--ro raw-pdu? binary
+---n area-mismatch
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro raw-pdu? binary
+---n rejected-adjacency
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro raw-pdu? binary
| +--ro reason? string
+---n protocols-supported-mismatch
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro raw-pdu? binary
| +--ro protocols* uint8
+---n lsp-error-detected
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro lsp-id? lsp-id
| +--ro raw-pdu? binary
| +--ro error-offset? uint32
| +--ro tlv-type? uint8
+---n adjacency-state-change
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro neighbor? string
| +--ro neighbor-system-id? system-id
| +--ro state? adj-state-type
| +--ro reason? string
+---n lsp-received
| +--ro routing-protocol-name? -> /rt:routing/
| | control-plane-protocols/
| | control-plane-protocol/name
| +--ro isis-level? level
| +--ro interface-name? if:interface-ref
| +--ro interface-level? level
| +--ro extended-circuit-id? extended-circuit-id
| +--ro lsp-id? lsp-id
| +--ro sequence? uint32
| +--ro received-timestamp? yang:timestamp
| +--ro neighbor-system-id? system-id
+---n lsp-generation
+--ro routing-protocol-name? -> /rt:routing/
| control-plane-protocols/
| control-plane-protocol/name
+--ro isis-level? level
+--ro lsp-id? lsp-id
+--ro sequence? uint32
+--ro send-timestamp? yang:timestamp2.1. IS-IS Configuration 💖
okay so the IS-IS configuration is split into two buckets ✨:
- Global parameters 🌍
- Per-interface configuration (see Section 2.4) 🎀
want more parameters? you can make additional modules to support them 🧚, but these additional modules MUST augment the "ietf-isis" module. no skipping that part bestie 🫶
the model has optional features too, and the config data nodes for those are optional as well 🦋. for example, being able to control the administrative state of a particular IS-IS instance is optional. if a device advertises the feature "admin-control", it's basically telling the client "hey, I can shut down a particular IS-IS instance" 🙈 that's a whole main character move ngl.
the global config holds the usual IS-IS vibes, like "lsp-mtu", "lsp-lifetime", "lsp-refresh", and "default-metric" 🌸
2.2. Multi-Topology Parameters 🌈
the model supports Multi-Topology (MT) IS-IS as defined in [RFC5120] 💜
the "topologies" container is what turns on support for the MT extensions. it's giving on/off switch energy 💅
the "name" used in the topology list should refer to an existing Routing Information Base (RIB) defined for the device [RFC8349] 🍓
some specific parameters can be set per topology, at both the global level and the interface level. for example, an interface metric can be defined per topology. so iconic 😭🔥
multiple address families (like IPv4 or IPv6) can also be enabled within the default topology. you do this with the "address-families" container, and it requires the "nlpid-control" feature to be supported 👑
2.3. Per-Level Parameters ✨
Okay so some parameters let you set a different value for level 1 and level 2 💖 For those, the parameter gets modeled as a container with three configuration locations:
- A top-level container 🌈 this one corresponds to "level-all", so whatever's set here applies to both levels.
- A level-1 container 🎀 for stuff that's specific to level 1.
- A level-2 container 🦋 for stuff that's specific to level 2.
+--rw priority
| +--rw value? uint8
| +--rw level-1
| | +--rw value? uint8
| +--rw level-2
| +--rw value? uint8Example:
<priority>
<value>250</value>
<level-1>
<value>100</value>
</level-1>
</priority>Here's the tea 🫖 an implementation MUST prefer a level-specific parameter over a top-level one. So if the priority is 100 for level 1 and 250 at the top level, the implementation has to use 100 for the level-1 priority and 250 for the level-2 priority. Main character energy for the specific setting, bestie 👑
Some parameters, like "overload bit" and "route preference", are not modeled to support per-level configuration 🙈 But if an implementation does support per-level configuration for those, it MUST augment the current model by adding both level-1 and level-2 containers, and it MUST reuse the existing configuration groupings. No reinventing the wheel, periodt 💅
Example of augmentation:
augment "/rt:routing/" +
"rt:control-plane-protocols/rt:control-plane-protocol"+
"/isis:isis/isis:overload" {
when "rt:type = 'isis:isis'" {
description
"This augments the IS-IS routing protocol when used.";
}
description
"This augments the IS-IS overload configuration
with per-level configuration.";
container level-1 {
uses isis:overload-global-cfg;
description
"Level-1 configuration.";
}
container level-2 {
uses isis:overload-global-cfg;
description
"Level-2 configuration.";
}
}If an implementation does not support per-level configuration for a parameter that's modeled with per-level configuration, it should advertise a deviation to announce that it doesn't support the level-1 and level-2 containers 🧚
And finally 🎀 if an implementation supports per-level configuration but doesn't support the "level-all" configuration, it should also advertise a deviation. Iykyk 😭
2.4. Per-Interface Parameters ✨
Okay, the per-interface section of the IS-IS instance is where all the interface-specific parameters live 🦋 The interface is modeled as a reference to an existing interface, as defined in the "ietf-interfaces" YANG module [RFC8343]. Bestie, just point at the interface you already have, no need to rebuild it 🌸
Each interface has some interface-specific parameters that can have a different per-level value, like we just talked about in the previous section. Here's the big rule 🔥 an interface-specific parameter MUST be preferred over an IS-IS global parameter. The interface wins, no cap.
Some parameters, like "hello-padding", are defined as containers so vendors can easily extend them with their own modules 💜
+--rw interfaces
+--rw interface* [name]
+--rw name if:interface-ref
+--rw enabled? boolean {admin-control}?
+--rw level-type? level
+--rw lsp-pacing-interval? rt-types:
| timer-value-\
| milliseconds
+--rw lsp-retransmit-interval? rt-types:
| timer-value-seconds16
+--rw passive? boolean
+--rw csnp-interval? rt-types:
| timer-value-seconds16
+--rw hello-padding
| +--rw enabled? boolean
+--rw mesh-group-enabled? mesh-group-state
+--rw mesh-group? uint8
+--rw interface-type? interface-type
+--rw tag* uint32 {prefix-tag}?
+--rw tag64* uint64 {prefix-tag64}?
+--rw node-flag? boolean {node-flag}?
+--rw hello-authentication
| +--rw (authentication-type)?
| | +--:(key-chain) {key-chain}?
| | | +--rw key-chain? key-chain:key-chain-ref
| | +--:(password)
| | +--rw key? string
| | +--rw crypto-algorithm? identityref
| +--rw level-1
| | +--rw (authentication-type)?
| | +--:(key-chain) {key-chain}?
| | | +--rw key-chain? key-chain:\
| | | key-chain-ref
| | +--:(password)
| | +--rw key? string
| | +--rw crypto-algorithm? identityref
| +--rw level-2
| +--rw (authentication-type)?
| +--:(key-chain) {key-chain}?
| | +--rw key-chain? key-chain:\
| | key-chain-ref
| +--:(password)
| +--rw key? string
| +--rw crypto-algorithm? identityref
+--rw hello-interval
| +--rw value? rt-types:timer-value-seconds16
| +--rw level-1
| | +--rw value? rt-types:timer-value-seconds16
| +--rw level-2
| +--rw value? rt-types:timer-value-seconds16
+--rw hello-multiplier
| +--rw value? uint16
| +--rw level-1
| | +--rw value? uint16
| +--rw level-2
| +--rw value? uint16
+--rw priority
| +--rw value? uint8
| +--rw level-1
| | +--rw value? uint8
| +--rw level-2
| +--rw value? uint8
+--rw metric
| +--rw value? wide-metric
| +--rw level-1
| | +--rw value? wide-metric
| +--rw level-2
| +--rw value? wide-metric
+--rw bfd {bfd}?
| +--rw enabled? boolean
| +--rw local-multiplier? multiplier
| | {client-base-cfg-parms}?
| +--rw (interval-config-type)? {client-base-cfg-parms}?
| +--:(tx-rx-intervals)
| | +--rw desired-min-tx-interval? uint32
| | +--rw required-min-rx-interval? uint32
| +--:(single-interval) {single-minimum-interval}?
| +--rw min-interval? uint32
+--rw address-families {nlpid-control}?
| +--rw address-family-list* [address-family]
| +--rw address-family iana-rt-types:address-family
+--rw mpls
| +--rw ldp
| +--rw igp-sync? boolean {ldp-igp-sync}?
+--rw fast-reroute {fast-reroute}?
| +--rw lfa {lfa}?
| +--rw candidate-enabled? boolean
| +--rw enabled? boolean
| +--rw remote-lfa {remote-lfa}?
| | +--rw enabled? boolean
| +--rw level-1
| | +--rw candidate-enabled? boolean
| | +--rw enabled? boolean
| | +--rw remote-lfa {remote-lfa}?
| | +--rw enabled? boolean
| +--rw level-2
| +--rw candidate-enabled? boolean
| +--rw enabled? boolean
| +--rw remote-lfa {remote-lfa}?
| +--rw enabled? boolean
+--ro adjacencies
| +--ro adjacency* []
| +--ro neighbor-sys-type? level
| +--ro neighbor-sysid? system-id
| +--ro neighbor-extended-circuit-id? extended-\
| | circuit-id
| +--ro neighbor-snpa? snpa
| +--ro usage? level
| +--ro hold-timer? rt-types:
| | timer-value-\
| | seconds16
| +--ro neighbor-priority? uint8
| +--ro lastuptime? yang:timestamp
| +--ro state? adj-state-type
+--ro event-counters
| +--ro adjacency-changes? uint32
| +--ro adjacency-number? uint32
| +--ro init-fails? uint32
| +--ro adjacency-rejects? uint32
| +--ro id-len-mismatch? uint32
| +--ro max-area-addresses-mismatch? uint32
| +--ro authentication-type-fails? uint32
| +--ro authentication-fails? uint32
| +--ro lan-dis-changes? uint32
+--ro packet-counters
| +--ro level* [level]
| +--ro level level-number
| +--ro iih
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro ish
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro esh
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro lsp
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro psnp
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro csnp
| | +--ro in? uint32
| | +--ro out? uint32
| +--ro unknown
| +--ro in? uint32
+--rw discontinuity-time? yang:date-and-time
+--rw topologies {multi-topology}?
+--rw topology* [name]
+--rw name ->
| ../../../../../../../../rt:\
| ribs/rib/name
+--rw metric
+--rw value? wide-metric
+--rw level-1
| +--rw value? wide-metric
+--rw level-2
+--rw value? wide-metric2.5. Authentication Parameters ✨
Okay, authentication 🔐 The module defined in this document lets you configure authentication through the "ietf-key-chain" module [RFC8177]. The IS-IS module imports "ietf-key-chain" and reuses some of its groupings, so you can set authentication both globally and per interface 💅
Here's the vibe 🌈 if global authentication is configured, an implementation SHOULD authenticate PSNPs (Partial Sequence Number PDUs), CSNPs (Complete Sequence Number PDUs), and LSPs (Link State PDUs) with the authentication parameters that were supplied. Hello PDUs (Protocol Data Units) are a different story, since their authentication can be activated on a per-interface basis 🦋
2.6. IGP/LDP Synchronization 🔗✨
okay so bestie, [RFC5443] is the spec that makes the IGP (the Interior Gateway Protocol) and LDP (the Label Distribution Protocol) actually talk to each other and stay in sync 🫶 and this model handles it with an "ldp-igp-sync" feature! 💖
the way it works: the mpls/ldp/igp-sync leaf under interface is what switches the feature on for a given interface 🎀 the mpls/ldp/igp-sync container in the global config is intentionally EMPTY 💅 it's not needed to turn anything on. it's just there as a placeholder so other stuff (like timers) can be bolted on later 🧚
2.7. ISO Parameters 🌸
okay so IS-IS is built on the ISO protocol suite, which means some ISO parameters might be needed 👑 no cap, that's the whole reason this section exists 💜
this module augments the "ietf-interfaces" module config so you can set selected ISO parameters 🦋
the clns-mtu parameter can be configured per interface 💖
2.8. IP FRR ⚡
the YANG module in this doc supports LFAs (Loop-Free Alternates) [RFC5286] and remote LFAs [RFC7490] as IP Fast Reroute (FRR) techniques 🔥 it's giving backup route realness 😭
other models can augment the "fast-reroute" container to add other FRR flavors 🌈 like Maximally Redundant Trees (MRTs) from [RFC7812], and Topology Independent LFA (TI-LFA) FRR from [SR-TI-LFA], etc. ✨
right now LFAs and remote LFAs can only be turned on at the interface level 🎯 the global "lfa" container is there but kept empty so vendors can add their own stuff on top, like policies 💅
remote LFAs are considered an extension of LFAs, so remote LFAs cannot be enabled if LFAs are not enabled 🙈 no LFA, no rLFA, periodt 💀
the "candidate-enabled" data leaf says that an interface can be used as a backup 🫶
2.9. Operational States 📊
okay the operational states are defined in the "ietf-isis" module, spread across a bunch of containers at different levels 💜 here's the tea 🍓
system-counters: gives you stats about the global system 📈
interface: gives you config state info for each interface 🎀
adjacencies: gives you state info about current IS-IS adjacencies 🤝
spf-log: logs SPF (Shortest Path First) events for an IS-IS instance 🧠 this SHOULD be implemented as a wrapping buffer 🔁
lsp-log: logs LSP events for an IS-IS instance, meaning an LSP getting received or a local LSP getting modified 📝 this SHOULD be implemented as a wrapping buffer 🔁 and the implementation MAY optionally log LSP refreshes ✨
local-rib: the IS-IS internal routing table 🗺️
database: the contents of the current Link State Database (LSDB) 🗂️
hostnames: system-ID-to-hostname mappings [RFC5301] 🏷️
fast-reroute: IP FRR state info 🔥
3. RPC Operations 🎬
the "ietf-isis" module defines two RPC operations 🎀
clear-database: resets the contents of a particular IS-IS database and restarts database synchronization with all neighbors 🔄
clear-adjacency: restarts a particular set of IS-IS adjacencies 💫
4. Notifications 🔔
the "ietf-isis" module defines these notifications, so buckle up 😭🫶
database-overload: this one gets sent when the IS-IS node's overload condition changes 🚨
lsp-too-large: this one gets sent when the system tries to propagate a PDU that is too large 📦💀
if-state-change: this one gets sent when an interface's state changes 🔌
corrupted-lsp-detected: this one gets sent when the IS-IS node discovers that an LSP that was previously stored in the LSDB, i.e., local memory, has become corrupted 🫠
attempt-to-exceed-max-sequence: this one gets sent when the system wraps the 32-bit sequence counter of an LSP 🔢
id-len-mismatch: this one gets sent when a PDU with a different value for the system ID length is received 🆔
max-area-addresses-mismatch: this one gets sent when a PDU with a different value for the Maximum Area Addresses is received 🗺️
own-lsp-purge: this one gets sent when the system receives a PDU with its own system ID and zero age 🧹
sequence-number-skipped: this one gets sent when the system receives a PDU with its own system ID and different contents 👀 the system has to reissue the LSP with a higher sequence number 📈
authentication-type-failure: this one gets sent when the system receives a PDU with the wrong authentication type field 🔐
authentication-failure: this one gets sent when the system receives a PDU with the wrong authentication information 🚫
version-skew: this one gets sent when the system receives a PDU with a different protocol version number 🆚
area-mismatch: this one gets sent when the system receives a Hello PDU from an IS that does not share any area address 🌍
rejected-adjacency: this one gets sent when the system receives a Hello PDU from an IS but does not establish an adjacency for some reason 🙅
protocols-supported-mismatch: this one gets sent when the system receives a non-pseudonode LSP that has no matching protocol supported 🤷
lsp-error-detected: this one gets sent when the system receives an LSP with a parse error 🧩
adjacency-state-change: this one gets sent when an IS-IS adjacency moves to the "up" state or the "down" state 🔀
lsp-received: this one gets sent when an LSP is received 📬
lsp-generation: this one gets sent when an LSP is regenerated 🔁
5. Interactions with Other YANG Modules 🤝
the "isis" container augments the "/rt:routing/rt:control-plane-protocols/control-plane-protocol" container of the "ietf-routing" module [RFC8349] with IS-IS-specific parameters 🧩
the "ietf-isis" module augments "/if:interfaces/if:interface" as defined by [RFC8343] with ISO-specific parameters 🔌
some IS-IS-specific route attributes get added to route objects in the "ietf-routing" module by augmenting "/rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route" 🛣️
the module in this doc uses some groupings from "ietf-keychain" [RFC8177] 🔑
the module reuses types from [RFC6991] and [RFC8294] 🎀
to support Bidirectional Forwarding Detection (BFD) for fast detection, the module relies on [RFC9314] ⚡
6. IS-IS YANG Module 💎
the following specifications are referenced in this module: [ISO-10589], [RFC1195], [RFC4090], [RFC5029], [RFC5120], [RFC5130], [RFC5286], [RFC5301], [RFC5302], [RFC5305], [RFC5307], [RFC5308], [RFC5443], [RFC5880], [RFC5881], [RFC6119], [RFC6232], [RFC6241], [RFC6991], [RFC7490], [RFC7794], [RFC7917], [RFC7981], [RFC8177], [RFC8294], [RFC8342], [RFC8343], [RFC8349], [RFC8405], [RFC8570], [RFC8706], and [RFC9314] 📚
<CODE BEGINS> file "ietf-isis@2022-10-19.yang"
module ietf-isis {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-isis";
prefix isis;
import ietf-routing {
prefix rt;
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA Version)";
}
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-key-chain {
prefix key-chain;
reference
"RFC 8177: YANG Data Model for Key Chains";
}
import ietf-routing-types {
prefix rt-types;
reference
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import iana-routing-types {
prefix iana-rt-types;
reference
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import ietf-bfd-types {
prefix bfd-types;
reference
"RFC 9314: YANG Data Model for Bidirectional Forwarding
Detection (BFD)";
}
organization
"IETF LSR Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/lsr/>
WG List: <mailto:lsr@ietf.org>
Editor: Stephane Litkowski
<mailto:slitkows.ietf@gmail.com>
Author: Derek Yeung
<mailto:derek@arrcus.com>
Author: Acee Lindem
<mailto:acee@cisco.com>
Author: Jeffrey Zhang
<mailto:zzhang@juniper.net>
Author: Ladislav Lhotka
<mailto:ladislav.lhotka@nic.cz>";
description
"This YANG module defines the generic configuration and
operational states for the IS-IS protocol common to all
vendor implementations. It is intended that the module
will be extended by vendors to define vendor-specific
IS-IS configuration parameters and policies -
for example, route maps or route policies.
This YANG data model conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8342.
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) 2022 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 Revised 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 9130; see the
RFC itself for full legal notices.";
reference
"RFC 8342: Network Management Datastore Architecture (NMDA)";
revision 2022-10-19 {
description
"Initial revision.";
reference
"RFC 9130: YANG Data Model for the IS-IS Protocol";
}
/* Identities */
identity isis {
base rt:routing-protocol;
description
"Identity for the IS-IS routing protocol.";
}
identity lsp-log-reason {
description
"Base identity for a Link State PDU (LSP)
change log reason.";
}
identity refresh {
base lsp-log-reason;
description
"Identity used when the LSP log reason is that an LSP
refresh was received.";
}
identity content-change {
base lsp-log-reason;
description
"Identity used when the LSP log reason is
a change in the contents of the LSP.";
}
identity frr-protection-method {
description
"Base identity for a Fast Reroute protection method.";
}
identity frr-protection-method-lfa {
base frr-protection-method;
description
"Loop-Free Alternate as defined in RFC 5286.";
reference
"RFC 5286: Basic Specification for IP Fast Reroute:
Loop-Free Alternates";
}
identity frr-protection-method-rlfa {
base frr-protection-method;
description
"Remote Loop-Free Alternate as defined in RFC 7490.";
reference
"RFC 7490: Remote Loop-Free Alternate (LFA)
Fast Reroute (FRR)";
}okay bestie, we're still deep in the YANG module and it's giving identities 💖 Here's the next batch of FRR protection methods and alternate types 🦋
identity frr-protection-method-rsvpte {
base frr-protection-method;
description
"RSVP-TE as defined in RFC 4090.";
reference
"RFC 4090: Fast Reroute Extensions to RSVP-TE for
LSP Tunnels";
}
identity frr-protection-available-type {
description
"Base identity for Fast Reroute protection types
provided by an alternate path.";
}
identity frr-protection-available-node-type {
base frr-protection-available-type;
description
"Node protection is provided by the alternate.";
}
identity frr-protection-available-link-type {
base frr-protection-available-type;
description
"Link protection is provided by the alternate.";
}
identity frr-protection-available-srlg-type {
base frr-protection-available-type;
description
"Shared Risk Link Group (SRLG) protection is provided by
the alternate.";
}
identity frr-protection-available-downstream-type {
base frr-protection-available-type;
description
"The alternate is downstream of the node in the path.";
}
identity frr-protection-available-other-type {
base frr-protection-available-type;
description
"The level of protection is unknown.";
}
identity frr-alternate-type {
description
"Base identity for the IP Fast Reroute alternate type.";
}
identity frr-alternate-type-equal-cost {
base frr-alternate-type;
description
"ECMP-based alternate.";
}
identity frr-alternate-type-lfa {
base frr-alternate-type;
description
"LFA-based alternate.";
}
identity frr-alternate-type-remote-lfa {
base frr-alternate-type;
description
"Remote-LFA-based alternate.";
}
identity frr-alternate-type-tunnel {
base frr-alternate-type;
description
"Tunnel-based alternate (such as RSVP-TE or GRE).";
}
identity frr-alternate-mrt {
base frr-alternate-type;
description
"MRT-based alternate.";
}
identity frr-alternate-tilfa {
base frr-alternate-type;
description
"TI-LFA-based alternate.";
}
identity frr-alternate-other {
base frr-alternate-type;
description
"Other type of alternate.";
}next up: the delay, loss and TLV flags 🌸 the "A" bit keeps showing up everywhere, so I'm just gonna let it be the main character 💅
identity unidirectional-link-delay-subtlv-flag {
description
"Base identity for the flag corresponding to the
Unidirectional Link Delay sub-TLV as defined in RFC 8570.";
reference
"RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
}
identity unidirectional-link-delay-subtlv-a-flag {
base unidirectional-link-delay-subtlv-flag;
description
"The 'A' bit field represents the Anomalous (A) bit.
The A bit is set when the measured value of
this parameter exceeds its configured
maximum threshold.
The A bit is cleared when the measured value
falls below its configured reuse threshold.
If the A bit is clear,
the value represents steady-state link performance.";
}
identity min-max-unidirectional-link-delay-subtlv-flag {
description
"Base identity for the flag corresponding to the Min/Max
Unidirectional Link Delay sub-TLV as defined in RFC 8570.";
reference
"RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
}
identity min-max-unidirectional-link-delay-subtlv-a-flag {
base min-max-unidirectional-link-delay-subtlv-flag;
description
"The 'A' bit field represents the Anomalous (A) bit.
The A bit is set when the measured value of
this parameter exceeds its configured
maximum threshold.
The A bit is cleared when the measured value
falls below its configured reuse threshold.
If the A bit is clear,
the value represents steady-state link performance.";
}
identity unidirectional-link-loss-subtlv-flag {
description
"Base identity for the flag corresponding to the
Unidirectional Link Loss sub-TLV as defined in RFC 8570.";
reference
"RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
}
identity unidirectional-link-loss-subtlv-a-flag {
base unidirectional-link-loss-subtlv-flag;
description
"The 'A' bit field represents the Anomalous (A) bit.
The A bit is set when the measured value of
this parameter exceeds its configured
maximum threshold.
The A bit is cleared when the measured value
falls below its configured reuse threshold.
If the A bit is clear,
the value represents steady-state link performance.";
}
identity tlv229-flag {
description
"Base identity for the flag corresponding to TLV 229
(M-Topologies) as defined in RFC 5120.";
reference
"RFC 5120: M-ISIS: Multi Topology (MT) Routing in
Intermediate System to Intermediate Systems (IS-ISs)";
}
identity tlv229-overload-flag {
base tlv229-flag;
description
"If set, the originator is overloaded
and must be avoided in the path calculation.";
}
identity tlv229-attached-flag {
base tlv229-flag;
description
"If set, the originator is attached to
another area using the referred metric.";
}
identity router-capability-flag {
description
"Base identity for the flag corresponding to the
Router Capability TLV as defined in RFC 7981.";
reference
"RFC 7981: IS-IS Extensions for Advertising Router
Information";
}
identity router-capability-flooding-flag {
base router-capability-flag;
description
"Quote from RFC 7981:
'If the S bit is set(1), the IS-IS Router CAPABILITY TLV
MUST be flooded across the entire routing domain. If the
S bit is not set(0), the TLV MUST NOT be leaked between
levels. This bit MUST NOT be altered during the TLV
leaking.'";
}
identity router-capability-down-flag {
base router-capability-flag;
description
"Quote from RFC 7981:
'When the IS-IS Router CAPABILITY TLV is leaked from
Level 2 (L2) to Level 1 (L1), the D bit MUST be set.
Otherwise, this bit MUST be clear. IS-IS Router
CAPABILITY TLVs with the D bit set MUST NOT be leaked from
Level 1 to Level 2. This is to prevent TLV looping.'";
}ngl the LSP flags are a whole lot of "set when" energy 🧚 these are the ISO 10589 attributes, so the vibes are very old-school but iconic 🍓
identity lsp-flag {
description
"Base identity for LSP attributes as defined in ISO 10589.";
reference
"ISO 10589: Intermediate System to Intermediate System
intra-domain routeing information exchange protocol
for use in conjunction with the protocol for providing
the connectionless-mode network service (ISO 8473)";
}
identity lsp-partitioned-flag {
base lsp-flag;
description
"Originator partition repair supported.";
}
identity lsp-attached-error-metric-flag {
base lsp-flag;
description
"Set when the originator is attached to
another area using the error metric.";
}
identity lsp-attached-delay-metric-flag {
base lsp-flag;
description
"Set when the originator is attached to
another area using the delay metric.";
}
identity lsp-attached-expense-metric-flag {
base lsp-flag;
description
"Set when the originator is attached to
another area using the expense metric.";
}
identity lsp-attached-default-metric-flag {
base lsp-flag;
description
"Set when the originator is attached to
another area using the default metric.";
}
identity lsp-overload-flag {
base lsp-flag;
description
"If set, the originator is overloaded
and must be avoided in the path calculation.";
}
identity lsp-l1-system-flag {
base lsp-flag;
description
"Set when the Intermediate System has an L1 type.";
}
identity lsp-l2-system-flag {
base lsp-flag;
description
"Set when the Intermediate System has an L2 type.";
}and now the feature definitions, where the module flexes its on/off switches 🎀 each one is a capability that an implementation may or may not support 🌈
/* Feature definitions */
feature osi-interface {
description
"Support of OSI-specific parameters on an interface.";
}
feature poi-tlv {
description
"Support of the Purge Originator Identification (POI) TLV.";
reference
"RFC 6232: Purge Originator Identification TLV for IS-IS";
}
feature ietf-spf-delay {
description
"Support for the IETF SPF delay algorithm.";
reference
"RFC 8405: Shortest Path First (SPF) Back-Off Delay Algorithm
for Link-State IGPs";
}
feature bfd {
description
"Support for detection of IS-IS neighbor reachability
via BFD.";
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD)
RFC 5881: Bidirectional Forwarding Detection (BFD)
for IPv4 and IPv6 (Single Hop)";
}
feature key-chain {
description
"Support of key chains for authentication.";
reference
"RFC 8177: YANG Data Model for Key Chains";
}
feature node-flag {
description
"Support for node flags for IS-IS prefixes.";
reference
"RFC 7794: IS-IS Prefix Attributes for Extended IPv4 and IPv6
Reachability";
}
feature node-tag {
description
"Support for node administrative tags for IS-IS
routing instances.";
reference
"RFC 7917: Advertising Node Administrative Tags in IS-IS";
}
feature ldp-igp-sync {
description
"Support for LDP IGP synchronization.";
reference
"RFC 5443: LDP IGP Synchronization";
}
feature fast-reroute {
description
"Support for IP Fast Reroute (IP FRR).";
}
feature nsr {
description
"Support for Non-Stop-Routing (NSR). The IS-IS NSR feature
allows a router with redundant control-plane capability
(e.g., dual Route Processor (RP) cards) to maintain its
state and adjacencies during planned and unplanned
IS-IS instance restarts. It differs from graceful restart
or Non-Stop Forwarding (NSF) in that no protocol signaling
or assistance from adjacent IS-IS neighbors is required to
recover control-plane state.";
}
feature lfa {
description
"Support for Loop-Free Alternates (LFAs).";
reference
"RFC 5286: Basic Specification for IP Fast Reroute:
Loop-Free Alternates";
}
feature remote-lfa {
description
"Support for remote LFAs (R-LFAs).";
reference
"RFC 7490: Remote Loop-Free Alternate (LFA)
Fast Reroute (FRR)";
}
feature overload-max-metric {
description
"Support of overload by setting all links to the maximum
link metric. In IS-IS, the overload bit is usually used to
signal that a node cannot be used as a transit node. The
'overload-max-metric' feature provides similar behavior,
also setting all the link metrics to MAX_METRIC.";
}
feature prefix-tag {
description
"Support for 32-bit prefix tags.";
reference
"RFC 5130: A Policy Control Mechanism in IS-IS Using
Administrative Tags";
}Okay bestie, the feature flags are up first 💖 Each feature is just a switch the module can turn on or off. Some of them point back to RFCs, so you can see where the idea came from 🦋
feature prefix-tag64 {
description
"Support for 64-bit prefix tags.";
reference
"RFC 5130: A Policy Control Mechanism in IS-IS Using
Administrative Tags";
}
feature auto-cost {
description
"Support for an IS-IS interface metric computation
according to a reference bandwidth.";
}
feature te-rid {
description
"Traffic Engineering router ID.";
reference
"RFC 5305: IS-IS Extensions for Traffic Engineering
RFC 6119: IPv6 Traffic Engineering in IS-IS";
}
feature max-ecmp {
description
"Sets the maximum number of ECMP paths.";
}
feature multi-topology {
description
"Support for Multi-Topology (MT) Routing.";
reference
"RFC 5120: M-ISIS: Multi Topology (MT) Routing in
Intermediate System to Intermediate Systems (IS-ISs)";
}
feature nlpid-control {
description
"Support for the advertisement of a Network Layer
Protocol Identifier within an IS-IS configuration.";
}
feature graceful-restart {
description
"Support for IS-IS graceful restart.";
reference
"RFC 8706: Restart Signaling for IS-IS";
}
feature lsp-refresh {
description
"Configuration of the LSP refresh interval.";
}
feature maximum-area-addresses {
description
"Support for 'maximum-area-addresses' configuration.";
}
feature admin-control {
description
"Administrative control of the protocol state.";
}Next up are the typedefs, which are the custom types the module uses for things like circuit IDs, levels, and system IDs. They're the building blocks for everything else, so they're giving foundation ✨
/* Type definitions */
typedef circuit-id {
type uint8;
description
"This type defines the circuit ID
associated with an interface.";
}
typedef extended-circuit-id {
type uint32;
description
"This type defines the extended circuit ID
associated with an interface.";
}
typedef interface-type {
type enumeration {
enum broadcast {
description
"Broadcast interface type.";
}
enum point-to-point {
description
"Point-to-point interface type.";
}
}
description
"This type defines the type of adjacency
to be established for the interface.
'interface-type' determines the type
of Hello message that is used.";
}
typedef level {
type enumeration {
enum level-1 {
description
"This enum indicates L1-only capability.";
}
enum level-2 {
description
"This enum indicates L2-only capability.";
}
enum level-all {
description
"This enum indicates capability for both levels.";
}
}
default "level-all";
description
"This type defines the IS-IS level of an object.";
}
typedef adj-state-type {
type enumeration {
enum up {
description
"This state indicates that the adjacency is established.";
}
enum down {
description
"This state indicates that the adjacency is
NOT established.";
}
enum init {
description
"This state indicates that the adjacency is being
established.";
}
enum failed {
description
"This state indicates that the adjacency has failed.";
}
}
description
"This type defines the states of an adjacency.";
}
typedef if-state-type {
type enumeration {
enum up {
description
"'up' state.";
}
enum down {
description
"'down' state.";
}
}
description
"This type defines the state of an interface.";
}
typedef level-number {
type uint8 {
range "1 .. 2";
}
description
"This type defines the current IS-IS level.";
}
typedef lsp-id {
type string {
pattern '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]'
+ '{4}\.[0-9][0-9]-[0-9][0-9]';
}
description
"This type defines the IS-IS LSP ID format using a
pattern. An example LSP ID is '0143.0438.AEF0.02-01'.";
}
typedef area-address {
type string {
pattern '[0-9A-Fa-f]{2}(\.[0-9A-Fa-f]{4}){0,6}';
}
description
"This type defines the area address format.";
}
typedef snpa {
type string {
length "0 .. 20";
}
description
"This type defines the Subnetwork Point of Attachment (SNPA)
format. The SNPA should be encoded according to the rules
specified for the particular type of subnetwork being used.
As an example, for an Ethernet subnetwork, the SNPA is
encoded as a Media Access Control (MAC) address, such as
'00aa.bbcc.ddee'.";
}
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 the IS-IS system ID by using a pattern.
An example system ID is '0143.0438.AEF0'.";
}
typedef extended-system-id {
type string {
pattern '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.'
+ '[0-9][0-9]';
}
description
"This type defines the IS-IS system ID using a pattern.
'extended-system-id' contains the pseudonode number
in addition to the system ID.
An example extended system ID is '0143.0438.AEF0.00'.";
}
typedef wide-metric {
type uint32 {
range "0 .. 16777215";
}
description
"This type defines the wide-style format of an IS-IS metric.";
}
typedef std-metric {
type uint8 {
range "0 .. 63";
}
description
"This type defines the old-style format of the IS-IS metric.";
}
typedef mesh-group-state {
type enumeration {
enum mesh-inactive {
description
"The interface is not part of a mesh group.";
}
enum mesh-set {
description
"The interface is part of a mesh group.";
}
enum mesh-blocked {
description
"LSPs must not be flooded over this interface.";
}
}
description
"This type describes the mesh group state of an interface.";
}Now we're onto the notification groupings 🔔 These bundle up the instance and interface info that gets attached to notifications, so you always know which IS-IS instance and interface you're looking at 👑
/* Grouping for notifications */
grouping notification-instance-hdr {
description
"Instance-specific IS-IS notification data grouping.";
leaf routing-protocol-name {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
description
"Name of the IS-IS instance.";
}
leaf isis-level {
type level;
description
"IS-IS level of the instance.";
}
}
grouping notification-interface-hdr {
description
"Interface-specific IS-IS notification data grouping.";
leaf interface-name {
type if:interface-ref;
description
"IS-IS interface name.";
}
leaf interface-level {
type level;
description
"IS-IS level of the interface.";
}
leaf extended-circuit-id {
type extended-circuit-id;
description
"Extended circuit ID of the interface.";
}
}Last bit for this stretch is the IP Fast Reroute groupings 🚀 They cover the global config, then the per-interface LFA settings, including remote LFA. Lots of little on/off switches here, so it's giving very organised energy 🧚
/* Groupings for IP Fast Reroute */
grouping instance-fast-reroute-config {
description
"This group defines the global configuration of IP
Fast Reroute (FRR).";
container fast-reroute {
if-feature "fast-reroute";
description
"This container may be augmented with global
parameters for IP FRR.";
container lfa {
if-feature "lfa";
description
"This container may be augmented with
global parameters for Loop-Free Alternates (LFAs).
The creation of this container has no effect on
LFA activation.";
}
}
}
grouping interface-lfa-config {
leaf candidate-enabled {
type boolean;
default "true";
description
"Enables the interface to be used as a backup.";
}
leaf enabled {
type boolean;
default "false";
description
"Activates the LFA. Per-prefix LFA computation is assumed.";
}
container remote-lfa {
if-feature "remote-lfa";
leaf enabled {
type boolean;
default "false";
description
"Activates the remote LFA (R-LFA).";
}
description
"Remote LFA configuration.";
}
description
"Grouping for LFA interface configuration.";
}
grouping interface-fast-reroute-config {
description
"This group defines the interface configuration of IP FRR.";
container fast-reroute {
if-feature "fast-reroute";
container lfa {
if-feature "lfa";
uses interface-lfa-config;
container level-1 {
uses interface-lfa-config;
description
"LFA level-1 configuration.";
}
container level-2 {
uses interface-lfa-config;
description
"LFA level-2 configuration.";
}
description
"LFA configuration.";
}
description
"Interface IP FRR configuration.";
}
}Okay so the IP FRR grouping is up next, and it's a whole vibe 🦋 It's all operational state (config false), so it's basically the stats board for protected and unprotected routes ✨
grouping instance-fast-reroute-state {
description
"IP FRR state data grouping.";
container protected-routes {
config false;
list address-family-stats {
key "address-family prefix alternate";
leaf address-family {
type iana-rt-types:address-family;
description
"Address family.";
}
leaf prefix {
type inet:ip-prefix;
description
"Protected prefix.";
}
leaf alternate {
type inet:ip-address;
description
"Alternate next hop for the prefix.";
}
leaf alternate-type {
type identityref {
base frr-alternate-type;
}
description
"Type of alternate.";
}
leaf best {
type boolean;
description
"Set when the alternate is the preferred alternate;
clear otherwise.";
}
leaf non-best-reason {
type string {
length "1..255";
}
description
"Information field that explains why the alternate
is not the best alternate. The length should be
limited to 255 Unicode characters. The expected format
is a single line of text.";
}
container protection-available {
leaf-list protection-types {
type identityref {
base frr-protection-available-type;
}
description
"This list contains a set of protection
types defined as identities.
An identity must be added for each type of
protection provided by the alternate.
As an example, if an alternate provides
SRLG, node, and link protection, three
identities must be added in this list:
one for SRLG protection, one for node
protection, and one for link protection.";
}
description
"Protection types provided by the alternate.";
}
leaf alternate-metric-1 {
type uint32;
description
"Metric from the Point of Local Repair (PLR) to the
destination through the alternate path.";
}
leaf alternate-metric-2 {
type uint32;
description
"Metric from the PLR to the alternate node.";
}
leaf alternate-metric-3 {
type uint32;
description
"Metric from the alternate node to the destination.";
}
description
"Per-address-family protected prefix statistics.";
}
description
"List of prefixes that are protected.";
}
container unprotected-routes {
config false;
list prefixes {
key "address-family prefix";
leaf address-family {
type iana-rt-types:address-family;
description
"Address family.";
}
leaf prefix {
type inet:ip-prefix;
description
"Unprotected prefix.";
}
description
"Per-address-family unprotected prefix statistics.";
}
description
"List of prefixes that are not protected.";
}
list protection-statistics {
key "frr-protection-method";
config false;
leaf frr-protection-method {
type identityref {
base frr-protection-method;
}
description
"Protection method used.";
}
list address-family-stats {
key "address-family";
leaf address-family {
type iana-rt-types:address-family;
description
"Address family.";
}
leaf total-routes {
type yang:gauge32;
description
"Total prefixes.";
}
leaf unprotected-routes {
type yang:gauge32;
description
"Total prefixes that are not protected.";
}
leaf protected-routes {
type yang:gauge32;
description
"Total prefixes that are protected.";
}
leaf link-protected-routes {
type yang:gauge32;
description
"Total prefixes that are link protected.";
}
leaf node-protected-routes {
type yang:gauge32;
description
"Total prefixes that are node protected.";
}
description
"Per-address-family protected prefix statistics.";
}
description
"Global protection statistics.";
}
}So the protected-routes list is keyed on address family, prefix, and alternate, which means each protected prefix gets an entry per alternate 💜 The protection-available container is where you list every kind of protection an alternate brings (SRLG, node, link, whatever applies), one identity each, and the three metrics cover the PLR-to-destination path, the PLR-to-alternate-node hop, and the alternate-node-to-destination hop 🧚
Next up are the routing table and local RIB groupings, plus the route properties grouping that rides along with them 🌸
/* Routing table and local Routing Information Base (RIB)
groupings */
grouping local-rib {
description
"Local RIB: RIB for routes computed by the local IS-IS
routing instance.";
container local-rib {
config false;
description
"Local RIB.";
list route {
key "prefix";
description
"Routes.";
leaf prefix {
type inet:ip-prefix;
description
"Destination prefix.";
}
container next-hops {
description
"Next hops for the route.";
list next-hop {
key "next-hop";
description
"List of next hops for the route.";
leaf outgoing-interface {
type if:interface-ref;
description
"Name of the outgoing interface.";
}
leaf next-hop {
type inet:ip-address;
description
"Next-hop address.";
}
}
}
leaf metric {
type uint32;
description
"Metric for this route.";
}
leaf level {
type level-number;
description
"Level number for this route.";
}
leaf route-tag {
type uint32;
description
"Route tag for this route.";
}
}
}
}
grouping route-content {
description
"IS-IS protocol-specific route properties grouping.";
leaf metric {
type uint32;
description
"IS-IS metric of a route.";
}
leaf-list tag {
type uint64;
description
"List of tags associated with the route. This list
provides a consolidated view of both 32-bit and 64-bit
tags (RFC 5130) available for the prefix.";
reference
"RFC 5130: A Policy Control Mechanism in IS-IS Using
Administrative Tags";
}
leaf route-type {
type enumeration {
enum l2-intra-area {
description
"Level-2 internal route. As per RFC 5302,
the prefix is directly connected to the
advertising router. It cannot be
distinguished from an L1->L2 inter-area
route.";
reference
"RFC 5302: Domain-Wide Prefix Distribution with
Two-Level IS-IS";
}
enum l1-intra-area {
description
"Level-1 internal route. As per RFC 5302,
the prefix is directly connected to the
advertising router.";
}
enum l2-external {
description
"Level-2 external route. As per RFC 5302,
such a route is learned from other IGPs.
It cannot be distinguished from an L1->L2
inter-area external route.";
}
enum l1-external {
description
"Level-1 external route. As per RFC 5302,
such a route is learned from other IGPs.";
}
enum l1-inter-area {
description
"These prefixes are learned via L2 routing.";
}
enum l1-inter-area-external {
description
"These prefixes are learned via L2 routing
towards a level-2 external route.";
}
}
description
"IS-IS route type.";
}
}The local-rib is the RIB the local IS-IS instance computed, keyed by prefix, with each route carrying its next hops, metric, level, and route tag 🎀 And route-content is the IS-IS-specific bit: metric, tags (both 32-bit and 64-bit ones, per RFC 5130 🏷️), and a route-type enum that leans on RFC 5302 for its definitions 💅
Now the adjacency state grouping, which is basically the neighbor roster 👑
/* Grouping definitions for configuration and operational states */
grouping adjacency-state {
container adjacencies {
config false;
list adjacency {
leaf neighbor-sys-type {
type level;
description
"Level capability of the neighboring system.";
}
leaf neighbor-sysid {
type system-id;
description
"The system ID of the neighbor.";
}
leaf neighbor-extended-circuit-id {
type extended-circuit-id;
description
"The circuit ID of the neighbor.";
}
leaf neighbor-snpa {
type snpa;
description
"The SNPA of the neighbor.";
}
leaf usage {
type level;
description
"Defines the level(s) activated for the adjacency.
On a point-to-point link, this might be level 1 and
level 2, but on a LAN, the usage will be level 1
between neighbors at level 1 or level 2 between
neighbors at level 2.";
}
leaf hold-timer {
type rt-types:timer-value-seconds16;
units "seconds";
description
"The holding time (in seconds) for this adjacency.
This value is based on received Hello PDUs and the
elapsed time since receipt.";
}
leaf neighbor-priority {
type uint8 {
range "0 .. 127";
}
description
"Priority of the neighboring IS for becoming the
Designated Intermediate System (DIS).";
}
leaf lastuptime {
type yang:timestamp;
description
"When the adjacency most recently entered the
'up' state, measured in hundredths of a
second since the last reinitialization of
the network management subsystem.
The value is 0 if the adjacency has never
been in the 'up' state.";
}
leaf state {
type adj-state-type;
description
"This leaf describes the state of the interface.";
}
description
"List of operational adjacencies.";
}
description
"This container lists the adjacencies of
the local node.";
}
description
"Adjacency state.";
}Each adjacency entry tells you the neighbor's level capability, system ID, circuit ID, and SNPA, plus how the adjacency is being used, its hold timer, its DIS priority, when it last came up, and its current state 🦋
Last but not least, the admin control grouping, which is the on/off switch for the whole protocol 🔥
grouping admin-control {
leaf enabled {
if-feature "admin-control";
type boolean;
default "true";
description
"Enables or disables the protocol.";
}
description
"Grouping for administrative control.";
}The enabled leaf only shows up when the admin-control feature is in play, and it defaults to "true" 💖
okay bestie, this part is all about the reusable YANG groupings: timers, authentication, metrics, overload, route preference, Hello settings and DIS priority 💅🫶
grouping ietf-spf-delay {
leaf initial-delay {
type rt-types:timer-value-milliseconds;
units "msec";
default "50";
description
"Delay used while in the QUIET state (milliseconds).";
}
leaf short-delay {
type rt-types:timer-value-milliseconds;
units "msec";
default "200";
description
"Delay used while in the SHORT_WAIT state (milliseconds).";
}
leaf long-delay {
type rt-types:timer-value-milliseconds;
units "msec";
default "5000";
description
"Delay used while in the LONG_WAIT state (milliseconds).";
}
leaf hold-down {
type rt-types:timer-value-milliseconds;
units "msec";
default "10000";
description
"This timer value defines the period without any changes
for the IGP to be considered stable (in milliseconds).";
}
leaf time-to-learn {
type rt-types:timer-value-milliseconds;
units "msec";
default "500";
description
"Duration used to learn all the IGP events
related to a single network event (milliseconds).";
}
leaf current-state {
type enumeration {
enum quiet {
description
"QUIET state.";
}
enum short-wait {
description
"SHORT_WAIT state.";
}
enum long-wait {
description
"LONG_WAIT state.";
}
}
config false;
description
"Current SPF Back-Off algorithm state.";
}
leaf remaining-time-to-learn {
type rt-types:timer-value-milliseconds;
units "msec";
config false;
description
"Remaining time until the time-to-learn timer fires.";
}
leaf remaining-hold-down {
type rt-types:timer-value-milliseconds;
units "msec";
config false;
description
"Remaining time until the hold-down timer fires.";
}
leaf last-event-received {
type yang:timestamp;
config false;
description
"Time of the last IGP event received.";
}
leaf next-spf-time {
type yang:timestamp;
config false;
description
"Time when the next SPF has been scheduled.";
}
leaf last-spf-time {
type yang:timestamp;
config false;
description
"Time of the last SPF computation.";
}
description
"Grouping for IETF SPF delay configuration and state.";
reference
"RFC 8405: Shortest Path First (SPF) Back-Off Delay Algorithm
for Link-State IGPs";
}
grouping node-tag-config {
description
"IS-IS node tag configuration state.";
container node-tags {
if-feature "node-tag";
list node-tag {
key "tag";
leaf tag {
type uint32;
description
"Node tag value.";
}
description
"List of tags.";
}
description
"Container for node administrative tags.";
}
}
grouping authentication-global-cfg {
choice authentication-type {
case key-chain {
if-feature "key-chain";
leaf key-chain {
type key-chain:key-chain-ref;
description
"Reference to a key chain.";
}
}
case password {
leaf key {
type string;
description
"This leaf specifies the authentication key. The
length of the key may be dependent on the
cryptographic algorithm.";
}
leaf crypto-algorithm {
type identityref {
base key-chain:crypto-algorithm;
}
description
"Cryptographic algorithm associated with a key.";
}
}
description
"Choice of authentication.";
}
description
"Grouping for global authentication configuration.";
}
grouping metric-type-global-cfg {
leaf value {
type enumeration {
enum wide-only {
description
"Advertises the new metric style only (RFC 5305).";
reference
"RFC 5305: IS-IS Extensions for Traffic Engineering";
}
enum old-only {
description
"Advertises the old metric style only (RFC 1195).";
reference
"RFC 1195: Use of OSI IS-IS for routing in TCP/IP and
dual environments";
}
enum both {
description
"Advertises both metric styles.";
}
}
description
"Type of metric to be generated:
- 'wide-only' means that only a new metric style
is generated.
- 'old-only' means that only an old metric style
is generated.
- 'both' means that both are advertised.
This leaf only affects IPv4 metrics.";
}
description
"Grouping for global metric style configuration.";
}
grouping metric-type-global-cfg-with-default {
leaf value {
type enumeration {
enum wide-only {
description
"Advertises the new metric style only (RFC 5305).";
reference
"RFC 5305: IS-IS Extensions for Traffic Engineering";
}
enum old-only {
description
"Advertises the old metric style only (RFC 1195).";
reference
"RFC 1195: Use of OSI IS-IS for routing in TCP/IP and
dual environments";
}
enum both {
description
"Advertises both metric styles.";
}
}
default "wide-only";
description
"Type of metric to be generated:
- 'wide-only' means that only a new metric style
is generated.
- 'old-only' means that only an old metric style
is generated.
- 'both' means that both are advertised.
This leaf only affects IPv4 metrics.";
}
description
"Grouping for global metric style configuration.";
}
grouping default-metric-global-cfg {
leaf value {
type wide-metric;
description
"Value of the metric.";
}
description
"Global default metric configuration grouping.";
}
grouping default-metric-global-cfg-with-default {
leaf value {
type wide-metric;
default "10";
description
"Value of the metric.";
}
description
"Global default metric configuration grouping.";
}
grouping overload-global-cfg {
leaf status {
type boolean;
default "false";
description
"This leaf specifies the overload status.";
}
description
"Grouping for overload bit configuration.";
}
grouping overload-max-metric-global-cfg {
leaf timeout {
type rt-types:timer-value-seconds16;
units "seconds";
description
"Timeout (in seconds) of the overload condition.";
}
description
"Overload maximum metric configuration grouping.";
}
grouping route-preference-global-cfg {
choice granularity {
case detail {
leaf internal {
type uint8;
description
"Protocol preference for internal routes.";
}
leaf external {
type uint8;
description
"Protocol preference for external routes.";
}
}
case coarse {
leaf default {
type uint8;
description
"Protocol preference for all IS-IS routes.";
}
}
description
"Choice for implementation of route preference.";
}
description
"Global route preference grouping.";
}
grouping hello-authentication-cfg {
choice authentication-type {
case key-chain {
if-feature "key-chain";
leaf key-chain {
type key-chain:key-chain-ref;
description
"Reference to a key chain.";
}
}
case password {
leaf key {
type string;
description
"Authentication key specification. The length of the
key may be dependent on the cryptographic algorithm.";
}
leaf crypto-algorithm {
type identityref {
base key-chain:crypto-algorithm;
}
description
"Cryptographic algorithm associated with a key.";
}
}
description
"Choice of authentication.";
}
description
"Grouping for Hello authentication.";
}
grouping hello-interval-cfg {
leaf value {
type rt-types:timer-value-seconds16;
units "seconds";
description
"Interval (in seconds) between successive Hello
messages.";
}
description
"Interval between Hello messages.";
}
grouping hello-interval-cfg-with-default {
leaf value {
type rt-types:timer-value-seconds16;
units "seconds";
default "10";
description
"Interval (in seconds) between successive Hello
messages.";
}
description
"Interval between Hello messages.";
}
grouping hello-multiplier-cfg {
leaf value {
type uint16;
description
"Number of missed Hello messages prior to
declaring the adjacency down.";
}
description
"Grouping for the number of missed Hello messages prior to
declaring the adjacency down.";
}
grouping hello-multiplier-cfg-with-default {
leaf value {
type uint16;
default "3";
description
"Number of missed Hello messages prior to
declaring the adjacency down.";
}
description
"Grouping for the number of missed Hello messages prior to
declaring the adjacency down.";
}
grouping priority-cfg {
leaf value {
type uint8 {
range "0 .. 127";
}
description
"Priority of the interface for DIS election.";
}
description
"Interface DIS election priority grouping.";
}
grouping priority-cfg-with-default {
leaf value {
type uint8 {
range "0 .. 127";
}
default "64";
description
"Priority of the interface for DIS election.";
}
description
"Interface DIS election priority grouping.";
}
grouping metric-cfg {
leaf value {
type wide-metric;
description
"Metric value.";
}
description
"Interface metric grouping.";
}
grouping metric-cfg-with-default {
leaf value {
type wide-metric;
default "10";
description
"Metric value.";
}
description
"Interface metric grouping.";
}Okay bestie, we're deep in the YANG module now 💅🎀 Every grouping here is a little reusable bundle of config and state, and the IS-IS instance pulls them all together like a bento box 🍱✨ Let's start with the global metric stuff 📏
grouping metric-parameters {
container metric-type {
uses metric-type-global-cfg-with-default;
container level-1 {
uses metric-type-global-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses metric-type-global-cfg;
description
"Configuration specific to level 2.";
}
description
"Metric style global configuration.";
}
container default-metric {
uses default-metric-global-cfg-with-default;
container level-1 {
uses default-metric-global-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses default-metric-global-cfg;
description
"Configuration specific to level 2.";
}
description
"Default metric global configuration.";
}
container auto-cost {
if-feature "auto-cost";
description
"Interface auto-cost configuration state.";
leaf enabled {
type boolean;
description
"Enables or disables interface auto-cost.";
}
leaf reference-bandwidth {
when "../enabled = 'true'" {
description
"Only when auto-cost is enabled.";
}
type uint32 {
range "1..4294967";
}
units "Mbits";
description
"Configures the reference bandwidth used to automatically
determine the interface cost (Mbits). The cost is the
reference bandwidth divided by the interface speed,
with 1 being the minimum cost.";
}
}
description
"Grouping for global metric parameters.";
}Next up is the high-availability bundle 🫶 It's got graceful restart and NSR, and graceful restart is the feature that keeps the routing going while the router is restarting, so it's giving reliability realness 🔥
grouping high-availability-parameters {
container graceful-restart {
if-feature "graceful-restart";
leaf enabled {
type boolean;
default "false";
description
"Enables graceful restart.";
}
leaf restart-interval {
type rt-types:timer-value-seconds16;
units "seconds";
description
"Interval (in seconds) to attempt graceful restart prior
to failure.";
}
leaf helper-enabled {
type boolean;
default "true";
description
"Enables a local IS-IS router as a graceful restart
helper.";
}
description
"Configuration of graceful restart.";
}
container nsr {
if-feature "nsr";
description
"Non-Stop Routing (NSR) configuration.";
leaf enabled {
type boolean;
default "false";
description
"Enables or disables NSR.";
}
}
description
"Grouping for high-availability parameters.";
}Now authentication 🔐 This one is main character energy because it wraps the global config for both LSPs and SNPs, and each level gets its own copy 💖
grouping authentication-parameters {
container authentication {
uses authentication-global-cfg;
container level-1 {
uses authentication-global-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses authentication-global-cfg;
description
"Configuration specific to level 2.";
}
description
"Authentication global configuration for
both LSPs and Sequence Number PDUs (SNPs).";
}
description
"Grouping for authentication parameters.";
}Address families are next 🌈 This is where you switch on which address families the instance is actually running, and it's gated behind the nlpid-control feature, so it only shows up if you've got that feature turned on ✨
grouping address-family-parameters {
container address-families {
if-feature "nlpid-control";
list address-family-list {
key "address-family";
leaf address-family {
type iana-rt-types:address-family;
description
"Address family.";
}
leaf enabled {
type boolean;
description
"Activates the address family.";
}
description
"List of address families and whether or not they
are activated.";
}
description
"Address family configuration.";
}
description
"Grouping for address family parameters.";
}Now the MPLS bits 🧚 There's a Traffic Engineering router ID for IPv4 and IPv6, which feeds into TLV 134 and TLV 140 respectively, plus a container for LDP IGP synchronization that's waiting to be augmented 🦋
grouping mpls-parameters {
container mpls {
container te-rid {
if-feature "te-rid";
description
"Stable IS-IS router IP address used for Traffic
Engineering.";
leaf ipv4-router-id {
type inet:ipv4-address;
description
"Router ID value that would be used in TLV 134.";
}
leaf ipv6-router-id {
type inet:ipv6-address;
description
"Router ID value that would be used in TLV 140.";
}
}
container ldp {
container igp-sync {
if-feature "ldp-igp-sync";
description
"This container may be augmented with global
parameters for LDP IGP synchronization.";
}
description
"LDP configuration.";
}
description
"MPLS configuration.";
}
description
"Grouping for MPLS global parameters.";
}LSP parameters are the knobs for the link state PDUs themselves 📦 We've got the maximum PDU size (defaulting to 1492 bytes), the lifetime, the refresh interval, and the Purge Originator Identification TLV toggle, which is iconic 👑
grouping lsp-parameters {
leaf lsp-mtu {
type uint16;
units "bytes";
default "1492";
description
"Maximum size of an LSP PDU in bytes.";
}
leaf lsp-lifetime {
type uint16 {
range "1..65535";
}
units "seconds";
description
"Lifetime of the router's LSPs in seconds.";
}
leaf lsp-refresh {
if-feature "lsp-refresh";
type rt-types:timer-value-seconds16;
units "seconds";
description
"Refresh interval of the router's LSPs in seconds.";
}
leaf poi-tlv {
if-feature "poi-tlv";
type boolean;
default "false";
description
"Enables the advertisement of the IS-IS Purge Originator
Identification TLV.";
}
description
"Grouping for LSP global parameters.";
}SPF parameters 🧮 This is where you cap the number of Equal-Cost Multi-Path paths and tune the IETF SPF delay algorithm, so the path calculation doesn't get overly chaotic 🌸
grouping spf-parameters {
container spf-control {
leaf paths {
if-feature "max-ecmp";
type uint16 {
range "1..65535";
}
description
"Maximum number of Equal-Cost Multi-Path (ECMP) paths.";
}
container ietf-spf-delay {
if-feature "ietf-spf-delay";
uses ietf-spf-delay;
description
"IETF SPF delay algorithm configuration.";
}
description
"SPF calculation control.";
}
description
"Grouping for SPF global parameters.";
}Now the big one 💅 instance-config is the whole IS-IS global configuration grouping, and it pulls in basically every bundle we just went through, plus the level type, system ID, area addresses, route preference, and overload settings. It's the main character of the whole module, no cap 👑
grouping instance-config {
description
"IS-IS global configuration grouping.";
uses admin-control;
leaf level-type {
type level;
default "level-all";
description
"Level of an IS-IS node. Can be 'level-1', 'level-2', or
'level-all'.";
}
leaf system-id {
type system-id;
description
"System ID of the node.";
}
leaf maximum-area-addresses {
if-feature "maximum-area-addresses";
type uint8;
default "3";
description
"Maximum areas supported.";
}
leaf-list area-address {
type area-address;
description
"List of areas supported by the protocol instance.";
}
uses lsp-parameters;
uses high-availability-parameters;
uses node-tag-config;
uses metric-parameters;
uses authentication-parameters;
uses address-family-parameters;
uses mpls-parameters;
uses spf-parameters;
uses instance-fast-reroute-config;
container preference {
uses route-preference-global-cfg;
description
"Router preference configuration for IS-IS
protocol instance route installation.";
}
container overload {
uses overload-global-cfg;
description
"Router protocol instance overload state configuration.";
}
container overload-max-metric {
if-feature "overload-max-metric";
uses overload-max-metric-global-cfg;
description
"Router protocol instance overload maximum
metric advertisement configuration.";
}
}Next is the state side of things 📊 instance-state brings together the SPF and LSP logs, the hostname database, the LSDB, the local RIB, the system counters and FRR state, plus a discontinuity timestamp that tells you the last time any counter got reset, or when the instance was created if nothing's happened since 🕰️
grouping instance-state {
description
"IS-IS instance operational state.";
uses spf-log;
uses lsp-log;
uses hostname-db;
uses lsdb;
uses local-rib;
uses system-counters;
uses instance-fast-reroute-state;
leaf discontinuity-time {
type yang:date-and-time;
description
"The time of the most recent occasion at which any one
or more of this IS-IS instance's counters suffered a
discontinuity. If no such discontinuities have occurred
since the IS-IS instance was last reinitialized, then
this node contains the time the IS-IS instance was
reinitialized, which normally occurs when it was
created.";
}
}Last but not least, multi-topology config 🗺️ Each topology gets its own default metric (with level-specific overrides) and its own node tags, so you can run different topologies side by side without them stepping on each other 🦋
grouping multi-topology-config {
description
"Per-topology configuration.";
container default-metric {
uses default-metric-global-cfg;
container level-1 {
uses default-metric-global-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses default-metric-global-cfg;
description
"Configuration specific to level 2.";
}
description
"Default metric per-topology configuration.";
}
uses node-tag-config;
}okay bestie, now we're in the good part: the groupings that set up interface config and the counters. the interface-config grouping is the big one, so let's look at it first 🎀
grouping interface-config {
description
"Interface configuration grouping.";
uses admin-control;
leaf level-type {
type level;
default "level-all";
description
"IS-IS level of the interface.";
}
leaf lsp-pacing-interval {
type rt-types:timer-value-milliseconds;
units "milliseconds";
default "33";
description
"Interval (in milliseconds) between LSP transmissions.";
}
leaf lsp-retransmit-interval {
type rt-types:timer-value-seconds16;
units "seconds";
description
"Interval (in seconds) between LSP retransmissions.";
}
leaf passive {
type boolean;
default "false";
description
"Indicates whether the interface is in passive mode (IS-IS
is not running, but the network is advertised).";
}
leaf csnp-interval {
type rt-types:timer-value-seconds16;
units "seconds";
default "10";
description
"Interval (in seconds) between Complete Sequence Number
Packet (CSNP) messages.";
}
container hello-padding {
leaf enabled {
type boolean;
default "true";
description
"IS-IS Hello padding activation. Enabled by default.";
}
description
"IS-IS Hello padding configuration.";
}
leaf mesh-group-enabled {
type mesh-group-state;
description
"IS-IS interface mesh group state.";
}
leaf mesh-group {
when "../mesh-group-enabled = 'mesh-set'" {
description
"Only valid when 'mesh-group-enabled' equals 'mesh-set'.";
}
type uint8;
description
"IS-IS interface mesh group ID.";
}
leaf interface-type {
type interface-type;
default "broadcast";
description
"Type of adjacency to be established for the interface.
This dictates the type of Hello messages that are used.";
}
leaf-list tag {
if-feature "prefix-tag";
type uint32;
description
"List of tags associated with the interface.";
}
leaf-list tag64 {
if-feature "prefix-tag64";
type uint64;
description
"List of 64-bit tags associated with the interface.";
}
leaf node-flag {
if-feature "node-flag";
type boolean;
default "false";
description
"Sets the prefix as a node representative prefix.";
}
container hello-authentication {
uses hello-authentication-cfg;
container level-1 {
uses hello-authentication-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses hello-authentication-cfg;
description
"Configuration specific to level 2.";
}
description
"Authentication type to be used in Hello messages.";
}
container hello-interval {
uses hello-interval-cfg-with-default;
container level-1 {
uses hello-interval-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses hello-interval-cfg;
description
"Configuration specific to level 2.";
}
description
"Interval between Hello messages.";
}
container hello-multiplier {
uses hello-multiplier-cfg-with-default;
container level-1 {
uses hello-multiplier-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses hello-multiplier-cfg;
description
"Configuration specific to level 2.";
}
description
"Hello multiplier configuration.";
}
container priority {
must '../interface-type = "broadcast"' {
error-message "Priority only applies to broadcast "
+ "interfaces.";
description
"Checks for a broadcast interface.";
}
uses priority-cfg-with-default;
container level-1 {
uses priority-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses priority-cfg;
description
"Configuration specific to level 2.";
}
description
"Priority for DIS election.";
}
container metric {
uses metric-cfg-with-default;
container level-1 {
uses metric-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses metric-cfg;
description
"Configuration specific to level 2.";
}
description
"Metric configuration.";
}
container bfd {
if-feature "bfd";
description
"BFD interface configuration.";
uses bfd-types:client-cfg-parms;
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD)
RFC 5881: Bidirectional Forwarding Detection
(BFD) for IPv4 and IPv6 (Single Hop)
RFC 9314: YANG Data Model for Bidirectional Forwarding
Detection (BFD)";
}
container address-families {
if-feature "nlpid-control";
list address-family-list {
key "address-family";
leaf address-family {
type iana-rt-types:address-family;
description
"Address family.";
}
description
"List of address families.";
}
description
"Interface address families.";
}
container mpls {
container ldp {
leaf igp-sync {
if-feature "ldp-igp-sync";
type boolean;
default "false";
description
"Enables IGP/LDP synchronization.";
}
description
"Configuration related to LDP.";
}
description
"MPLS configuration for IS-IS interfaces.";
}
uses interface-fast-reroute-config;
}the multi-topology version of the interface config is a much smaller bundle, just the metric knobs, and it's giving very focused energy 💅
grouping multi-topology-interface-config {
description
"IS-IS interface topology configuration.";
container metric {
uses metric-cfg;
container level-1 {
uses metric-cfg;
description
"Configuration specific to level 1.";
}
container level-2 {
uses metric-cfg;
description
"Configuration specific to level 2.";
}
description
"Metric IS-IS interface configuration.";
}
}next up is the interface state grouping, which is where the operational data lives 🦋
grouping interface-state {
description
"IS-IS interface operational state.";
uses adjacency-state;
uses event-counters;
uses packet-counters;
leaf discontinuity-time {
type yang:date-and-time;
description
"The time of the most recent occasion at which any one
or more of this IS-IS interface's counters suffered a
discontinuity. If no such discontinuities have occurred
since the IS-IS interface was last reinitialized, then
this node contains the time the IS-IS interface was
reinitialized, which normally occurs when it was
created.";
}
}
/* Grouping for the hostname database */
grouping hostname-db {
container hostnames {
config false;
list hostname {
key "system-id";
leaf system-id {
type system-id;
description
"System ID associated with the hostname.";
}
leaf hostname {
type string {
length "1..255";
}
description
"Hostname associated with the system ID
as defined in RFC 5301.";
reference
"RFC 5301: Dynamic Hostname Exchange Mechanism
for IS-IS";
}
description
"List of system ID / hostname associations.";
}
description
"Hostname-to-system-ID mapping database.";
}
description
"Grouping for hostname-to-system-ID mapping database.";
}
/* Groupings for counters */
grouping system-counters {
container system-counters {
config false;
list level {
key "level";
leaf level {
type level-number;
description
"IS-IS level.";
}
leaf corrupted-lsps {
type uint32;
description
"Number of corrupted in-memory LSPs detected.
LSPs received from the wire with a bad
checksum are silently dropped and not counted.
LSPs received from the wire with parse errors
are counted by 'lsp-errors'.";
}
leaf authentication-type-fails {
type uint32;
description
"Number of authentication type mismatches.";
}
leaf authentication-fails {
type uint32;
description
"Number of authentication key failures.";
}
leaf database-overload {
type uint32;
description
"Number of times the database has become
overloaded.";
}
leaf own-lsp-purge {
type uint32;
description
"Number of times a zero-aged copy of the system's
own LSP is received from some other IS-IS node.";
}
leaf manual-address-drop-from-area {
type uint32;
description
"Number of times a manual address
has been dropped from the area.";
}
leaf max-sequence {
type uint32;
description
"Number of times the system has attempted
to exceed the maximum sequence number.";
}
leaf sequence-number-skipped {
type uint32;
description
"Number of times a sequence number skip has
occurred.";
}
leaf id-len-mismatch {
type uint32;
description
"Number of times a PDU is received with a
different value for the ID field length
than that of the receiving system.";
}
leaf partition-changes {
type uint32;
description
"Number of partition changes detected.";
}
leaf lsp-errors {
type uint32;
description
"Number of LSPs received with errors.";
}
leaf spf-runs {
type uint32;
description
"Number of times SPF was run at this level.";
}
description
"List of supported levels.";
}
description
"List of counters for the IS-IS protocol instance.";
}
description
"Grouping for IS-IS system counters.";
}the hostname database maps system IDs to hostnames, and the counters track every "oops" the protocol instance has seen per level. the vibes are very much "we keep receipts" 🧾💜
okay bestie, the interface counters are next 📊 these are the stats that tell you what your IS-IS interface has been through, and every single field is a uint32 counter 💅
grouping event-counters {
container event-counters {
config false;
leaf adjacency-changes {
type uint32;
description
"The number of times an adjacency state change has
occurred on this interface.";
}
leaf adjacency-number {
type uint32;
description
"The number of adjacencies on this interface.";
}
leaf init-fails {
type uint32;
description
"The number of times initialization of this interface has
failed. This counts events such as Point-to-Point
Protocol (PPP) Network Control Protocol (NCP) failures.
Failures to form an adjacency are counted by
'adjacency-rejects'.";
}
leaf adjacency-rejects {
type uint32;
description
"The number of times an adjacency has been
rejected on this interface.";
}
leaf id-len-mismatch {
type uint32;
description
"The number of times an IS-IS PDU with an ID
field length different from that for this
system has been received on this interface.";
}
leaf max-area-addresses-mismatch {
type uint32;
description
"The number of times an IS-IS PDU has been
received on this interface with the
max area address field differing from that of
this system.";
}
leaf authentication-type-fails {
type uint32;
description
"Number of authentication type mismatches.";
}
leaf authentication-fails {
type uint32;
description
"Number of authentication key failures.";
}
leaf lan-dis-changes {
type uint32;
description
"The number of times the DIS has changed on this
interface at this level. If the interface type is
'point-to-point', the count is zero.";
}
description
"IS-IS interface event counters.";
}
description
"Grouping for IS-IS interface event counters.";
}next up: the packet counters, which count every single type of PDU per level, IIH, ISH, ESH, LSP, PSNP, CSNP and unknown, in and out 🧚
grouping packet-counters {
container packet-counters {
config false;
list level {
key "level";
leaf level {
type level-number;
description
"IS-IS level.";
}
container iih {
leaf in {
type uint32;
description
"Received IS-IS Hello (IIH) PDUs.";
}
leaf out {
type uint32;
description
"Sent IIH PDUs.";
}
description
"Number of IIH PDUs received/sent.";
}
container ish {
leaf in {
type uint32;
description
"Received Intermediate System Hello (ISH) PDUs.";
}
leaf out {
type uint32;
description
"Sent ISH PDUs.";
}
description
"ISH PDUs received/sent.";
}
container esh {
leaf in {
type uint32;
description
"Received End System Hello (ESH) PDUs.";
}
leaf out {
type uint32;
description
"Sent ESH PDUs.";
}
description
"Number of ESH PDUs received/sent.";
}
container lsp {
leaf in {
type uint32;
description
"Received Link State PDU (LSP) PDUs.";
}
leaf out {
type uint32;
description
"Sent LSP PDUs.";
}
description
"Number of LSP PDUs received/sent.";
}
container psnp {
leaf in {
type uint32;
description
"Received Partial Sequence Number PDU (PSNP) PDUs.";
}
leaf out {
type uint32;
description
"Sent PSNP PDUs.";
}
description
"Number of PSNP PDUs received/sent.";
}
container csnp {
leaf in {
type uint32;
description
"Received Complete Sequence Number PDU (CSNP) PDUs.";
}
leaf out {
type uint32;
description
"Sent CSNP PDUs.";
}
description
"Number of CSNP PDUs received/sent.";
}
container unknown {
leaf in {
type uint32;
description
"Received unknown PDUs.";
}
description
"Number of unknown PDUs received.";
}
description
"List of packet counters for supported levels.";
}
description
"Packet counters per IS-IS level.";
}
description
"Grouping for packet counters per IS-IS level.";
}the log buffers are up next, and they're giving "wrapping buffer" energy: the newest events always get the biggest ID 🔁
/* Groupings for various log buffers */
grouping spf-log {
container spf-log {
config false;
list event {
key "id";
leaf id {
type yang:counter32;
description
"Event identifier. A purely internal value.
The most recent events are expected to have a bigger
ID number.";
}
leaf spf-type {
type enumeration {
enum full {
description
"Full SPF computation.";
}
enum route-only {
description
"SPF computation of route reachability
only.";
}
}
description
"Type of SPF computation performed.";
}
leaf level {
type level-number;
description
"IS-IS level number for the SPF computation.";
}
leaf schedule-timestamp {
type yang:timestamp;
description
"Timestamp of when the SPF computation was
scheduled.";
}
leaf start-timestamp {
type yang:timestamp;
description
"Timestamp of when the SPF computation started.";
}
leaf end-timestamp {
type yang:timestamp;
description
"Timestamp of when the SPF computation ended.";
}
list trigger-lsp {
key "lsp";
leaf lsp {
type lsp-id;
description
"LSP ID of the LSP that triggered the SPF
computation.";
}
leaf sequence {
type uint32;
description
"Sequence number of the LSP that triggered the SPF
computation.";
}
description
"This list includes the LSPs that triggered the
SPF computation.";
}
description
"List of computation events. Implemented as a
wrapping buffer.";
}
description
"This container lists the SPF computation events.";
}
description
"Grouping for SPF log events.";
}
grouping lsp-log {
container lsp-log {
config false;
list event {
key "id";
leaf id {
type yang:counter32;
description
"Event identifier. A purely internal value.
The most recent events are expected to have a bigger
ID number.";
}
leaf level {
type level-number;
description
"IS-IS level number for the LSP.";
}
container lsp {
leaf lsp {
type lsp-id;
description
"LSP ID of the LSP.";
}
leaf sequence {
type uint32;
description
"Sequence number of the LSP.";
}
description
"LSP identification container for either the received
LSP or the locally generated LSP.";
}
leaf received-timestamp {
type yang:timestamp;
description
"This is the timestamp when the LSP was received.
In the case of a local LSP update, the timestamp refers
to the LSP origination time.";
}
leaf reason {
type identityref {
base lsp-log-reason;
}
description
"Type of LSP change.";
}
description
"List of LSP events. Implemented as a wrapping buffer.";
}
description
"This container lists the LSP log.
Local LSP modifications are also included in the list.";
}
description
"Grouping for the LSP log.";
}and now the LSDB stuff 🍓 the TLV grouping and the unknown-TLVs grouping mean that anything your implementation doesn't recognise can still get carried around as raw hex, which is honestly iconic of it
/* Groupings for the Link State Database (LSDB) descriptions */
/* Unknown TLV and sub-TLV descriptions */
grouping tlv {
description
"Type-Length-Value (TLV).";
leaf type {
type uint16;
description
"TLV type.";
}
leaf length {
type uint16;
description
"TLV length (octets).";
}
leaf value {
type yang:hex-string;
description
"TLV value.";
}
}
grouping unknown-tlvs {
description
"Unknown TLVs grouping. Used for unknown TLVs or
unknown sub-TLVs.";
container unknown-tlvs {
description
"All unknown TLVs.";
list unknown-tlv {
description
"Unknown TLV.";
uses tlv;
}
}
}last bit of this chunk: the prefix reachability groupings 🌸 these hold the extended attributes for IPv4 and IPv6 prefixes, plus the source router IDs for each
/* TLVs and sub-TLVs for prefixes */
grouping prefix-reachability-attributes {
description
"Grouping for extended reachability attributes of an
IPv4 or IPv6 prefix.";
leaf external-prefix-flag {
type boolean;
description
"External prefix flag.";
}
leaf readvertisement-flag {
type boolean;
description
"Re-advertisement flag.";
}
leaf node-flag {
type boolean;
description
"Node flag.";
}
}
grouping prefix-ipv4-source-router-id {
description
"Grouping for the IPv4 source router ID of a prefix
advertisement.";
leaf ipv4-source-router-id {
type inet:ipv4-address;
description
"IPv4 source router ID address.";
}
}
grouping prefix-ipv6-source-router-id {
description
"Grouping for the IPv6 source router ID of a prefix
advertisement.";
leaf ipv6-source-router-id {
type inet:ipv6-address;
description
"IPv6 source router ID address.";
}
}Okay so the prefix groupings are up next, and they're giving organized 💅 Each one bundles up the attributes for a prefix, and the neighbor stuff comes right after. Let's go 🦋
grouping prefix-attributes-extension {
description
"Prefix extended attributes as defined in RFC 7794.";
reference
"RFC 7794: IS-IS Prefix Attributes for Extended IPv4 and IPv6
Reachability";
uses prefix-reachability-attributes;
uses prefix-ipv4-source-router-id;
uses prefix-ipv6-source-router-id;
}
grouping prefix-ipv4-std {
description
"Grouping for attributes of an IPv4 standard prefix
as defined in RFC 1195.";
reference
"RFC 1195: Use of OSI IS-IS for routing in TCP/IP and
dual environments";
leaf ip-prefix {
type inet:ipv4-address;
description
"IPv4 prefix address.";
}
leaf prefix-len {
type uint8;
description
"IPv4 prefix length (in bits).";
}
leaf i-e {
type boolean;
description
"Internal or external (I/E) metric bit value.
Set to 'false' to indicate an internal metric.";
}
container default-metric {
leaf metric {
type std-metric;
description
"Default IS-IS metric for the IPv4 prefix.";
}
description
"IS-IS default metric container.";
}
container delay-metric {
leaf metric {
type std-metric;
description
"IS-IS delay metric for the IPv4 prefix.";
}
leaf supported {
type boolean;
default "false";
description
"Indicates whether the IS-IS delay metric is supported.";
}
description
"IS-IS delay metric container.";
}
container expense-metric {
leaf metric {
type std-metric;
description
"IS-IS expense metric for the IPv4 prefix.";
}
leaf supported {
type boolean;
default "false";
description
"Indicates whether the IS-IS expense metric is supported.";
}
description
"IS-IS expense metric container.";
}
container error-metric {
leaf metric {
type std-metric;
description
"This leaf describes the IS-IS error metric value.";
}
leaf supported {
type boolean;
default "false";
description
"Indicates whether the IS-IS error metric is supported.";
}
description
"IS-IS error metric container.";
}
}
grouping prefix-ipv4-extended {
description
"Grouping for attributes of an IPv4 extended prefix
as defined in RFC 5305.";
reference
"RFC 5305: IS-IS Extensions for Traffic Engineering";
leaf up-down {
type boolean;
description
"Value of the up/down bit.
Set to 'true' when the prefix has been advertised down
the hierarchy.";
}
leaf ip-prefix {
type inet:ipv4-address;
description
"IPv4 prefix address.";
}
leaf prefix-len {
type uint8;
description
"IPv4 prefix length (in bits).";
}
leaf metric {
type wide-metric;
description
"IS-IS wide metric value.";
}
leaf-list tag {
type uint32;
description
"List of 32-bit tags associated with the IPv4 prefix.";
}
leaf-list tag64 {
type uint64;
description
"List of 64-bit tags associated with the IPv4 prefix.";
}
uses prefix-attributes-extension;
}
grouping prefix-ipv6-extended {
description
"Grouping for attributes of an IPv6 prefix
as defined in RFC 5308.";
reference
"RFC 5308: Routing IPv6 with IS-IS";
leaf up-down {
type boolean;
description
"Value of the up/down bit.
Set to 'true' when the prefix has been advertised down
the hierarchy.";
}
leaf ip-prefix {
type inet:ipv6-address;
description
"IPv6 prefix address.";
}
leaf prefix-len {
type uint8;
description
"IPv6 prefix length (in bits).";
}
leaf metric {
type wide-metric;
description
"IS-IS wide metric value.";
}
leaf-list tag {
type uint32;
description
"List of 32-bit tags associated with the IPv6 prefix.";
}
leaf-list tag64 {
type uint64;
description
"List of 64-bit tags associated with the IPv6 prefix.";
}
uses prefix-attributes-extension;
}
/* TLVs and sub-TLVs for neighbors */
grouping neighbor-link-attributes {
description
"Grouping for link attributes as defined
in RFC 5029.";
reference
"RFC 5029: Definition of an IS-IS Link Attribute Sub-TLV";
leaf link-attributes-flags {
type uint16;
description
"Flags for the link attributes.";
}
}
grouping neighbor-gmpls-extensions {
description
"Grouping for GMPLS attributes of a neighbor as defined
in RFC 5307.";
reference
"RFC 5307: IS-IS Extensions in Support of Generalized
Multi-Protocol Label Switching (GMPLS)";
leaf link-local-id {
type uint32;
description
"Local identifier of the link.";
}
leaf remote-local-id {
type uint32;
description
"Remote identifier of the link.";
}
leaf protection-capability {
type uint8;
description
"Describes the protection capabilities
of the link. This is the value of the
first octet of the sub-TLV type 20 value.";
}
container interface-switching-capability {
description
"Interface switching capabilities of the link.";
leaf switching-capability {
type uint8;
description
"Switching capability of the link.";
}
leaf encoding {
type uint8;
description
"Type of encoding of the LSP being used.";
}
container max-lsp-bandwidths {
description
"Per-priority maximum LSP bandwidths.";
list max-lsp-bandwidth {
leaf priority {
type uint8 {
range "0 .. 7";
}
description
"Priority from 0 to 7.";
}
leaf bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Maximum LSP bandwidth.";
}
description
"List of maximum LSP bandwidths for different
priorities.";
}
}
container tdm-specific {
when '../switching-capability = 100';
description
"Switching-capability-specific information applicable
when the switching type is Time-Division Multiplexing
(TDM).";
leaf minimum-lsp-bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Minimum LSP bandwidth.";
}
leaf indication {
type uint8;
description
"Indicates whether the interface supports Standard
or Arbitrary SONET/SDH (Synchronous Optical Network /
Synchronous Digital Hierarchy).";
}
}
container psc-specific {
when "../switching-capability >= 1 and
../switching-capability <= 4";
description
"Switching-capability-specific information applicable
when the switching type is PSC1, PSC2, PSC3, or PSC4
('PSC' stands for 'Packet Switching Capability').";
leaf minimum-lsp-bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Minimum LSP bandwidth.";
}
leaf mtu {
type uint16;
units "bytes";
description
"Interface MTU.";
}
}
}
}okay so this is where the neighbor groupings start getting spicy 🔥 it's all the TE and metric attributes for each adjacency, pulled from the RFCs it cites 💅
grouping neighbor-extended-te-extensions {
description
"Grouping for TE attributes of a neighbor as defined
in RFC 8570.";
reference
"RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
container unidirectional-link-delay {
description
"Container for the average delay
from the local neighbor to the remote neighbor.";
container flags {
leaf-list unidirectional-link-delay-subtlv-flags {
type identityref {
base unidirectional-link-delay-subtlv-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"Unidirectional Link Delay sub-TLV flags.";
}
leaf value {
type uint32;
units "usec";
description
"Delay value expressed in microseconds.";
}
}
container min-max-unidirectional-link-delay {
description
"Container for the minimum and maximum delay
from the local neighbor to the remote neighbor.";
container flags {
leaf-list min-max-unidirectional-link-delay-subtlv-flags {
type identityref {
base min-max-unidirectional-link-delay-subtlv-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"Min/Max Unidirectional Link Delay sub-TLV flags.";
}
leaf min-value {
type uint32;
units "usec";
description
"Minimum delay value expressed in microseconds.";
}
leaf max-value {
type uint32;
units "usec";
description
"Maximum delay value expressed in microseconds.";
}
}
container unidirectional-link-delay-variation {
description
"Container for the average delay variation
from the local neighbor to the remote neighbor.";
leaf value {
type uint32;
units "usec";
description
"Delay variation value expressed in microseconds.";
}
}
container unidirectional-link-loss {
description
"Container for packet loss from the local neighbor to the
remote neighbor.";
container flags {
leaf-list unidirectional-link-loss-subtlv-flags {
type identityref {
base unidirectional-link-loss-subtlv-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"Unidirectional Link Loss sub-TLV flags.";
}
leaf value {
type uint32;
units "percent";
description
"Link packet loss expressed as a percentage of
the total traffic sent over a configurable interval.";
}
}
container unidirectional-link-residual-bandwidth {
description
"Container for the residual bandwidth
from the local neighbor to the remote neighbor.";
leaf value {
type rt-types:bandwidth-ieee-float32;
units "Bps";
description
"Residual bandwidth.";
}
}
container unidirectional-link-available-bandwidth {
description
"Container for the available bandwidth
from the local neighbor to the remote neighbor.";
leaf value {
type rt-types:bandwidth-ieee-float32;
units "Bps";
description
"Available bandwidth.";
}
}
container unidirectional-link-utilized-bandwidth {
description
"Container for the utilized bandwidth
from the local neighbor to the remote neighbor.";
leaf value {
type rt-types:bandwidth-ieee-float32;
units "Bps";
description
"Utilized bandwidth.";
}
}
}
grouping neighbor-te-extensions {
description
"Grouping for TE attributes of a neighbor as defined
in RFC 5305.";
reference
"RFC 5305: IS-IS Extensions for Traffic Engineering";
leaf admin-group {
type uint32;
description
"Administrative Group / Resource Class/Color.";
}
container local-if-ipv4-addrs {
description
"All local interface IPv4 addresses.";
leaf-list local-if-ipv4-addr {
type inet:ipv4-address;
description
"List of local interface IPv4 addresses.";
}
}
container remote-if-ipv4-addrs {
description
"All remote interface IPv4 addresses.";
leaf-list remote-if-ipv4-addr {
type inet:ipv4-address;
description
"List of remote interface IPv4 addresses.";
}
}
leaf te-metric {
type uint32;
description
"TE metric.";
}
leaf max-bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Maximum bandwidth.";
}
leaf max-reservable-bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Maximum reservable bandwidth.";
}
container unreserved-bandwidths {
description
"All unreserved bandwidths.";
list unreserved-bandwidth {
leaf priority {
type uint8 {
range "0 .. 7";
}
description
"Priority from 0 to 7.";
}
leaf unreserved-bandwidth {
type rt-types:bandwidth-ieee-float32;
description
"Unreserved bandwidth.";
}
description
"List of unreserved bandwidths for different
priorities.";
}
}
}
grouping neighbor-extended {
description
"Grouping for attributes of an IS-IS extended neighbor.";
leaf neighbor-id {
type extended-system-id;
description
"System ID of the extended neighbor.";
}
container instances {
description
"List of all adjacencies between the local
system and the neighbor system ID.";
list instance {
key "id";
leaf id {
type uint32;
description
"Unique identifier of an instance of a
particular neighbor.";
}
leaf metric {
type wide-metric;
description
"IS-IS wide metric for the extended neighbor.";
}
uses neighbor-gmpls-extensions;
uses neighbor-te-extensions;
uses neighbor-extended-te-extensions;
uses neighbor-link-attributes;
uses unknown-tlvs;
description
"Instance of a particular adjacency.";
}
}
}
grouping neighbor {
description
"IS-IS standard neighbor grouping.";
leaf neighbor-id {
type extended-system-id;
description
"IS-IS neighbor system ID.";
}
container instances {
description
"List of all adjacencies between the local
system and the neighbor system ID.";
list instance {
key "id";
leaf id {
type uint32;
description
"Unique identifier of an instance of a
particular neighbor.";
}
leaf i-e {
type boolean;
description
"Internal or external (I/E) metric bit value.
Set to 'false' to indicate an internal metric.";
}
container default-metric {
leaf metric {
type std-metric;
description
"IS-IS default metric value.";
}
description
"IS-IS default metric container.";
}
container delay-metric {
leaf metric {
type std-metric;
description
"IS-IS delay metric value.";
}
leaf supported {
type boolean;
default "false";
description
"IS-IS delay metric supported.";
}
description
"IS-IS delay metric container.";
}
container expense-metric {
leaf metric {
type std-metric;
description
"IS-IS expense metric value.";
}
leaf supported {
type boolean;
default "false";
description
"IS-IS expense metric supported.";
}
description
"IS-IS expense metric container.";
}
container error-metric {
leaf metric {
type std-metric;
description
"IS-IS error metric value.";
}
leaf supported {
type boolean;
default "false";
description
"IS-IS error metric supported.";
}
description
"IS-IS error metric container.";
}
description
"Instance of a particular adjacency as defined in
ISO 10589.";
reference
"ISO 10589: Intermediate System to Intermediate System
intra-domain routeing information exchange protocol
for use in conjunction with the protocol for providing
the connectionless-mode network service (ISO 8473)";
}
}
}
/* Top-level TLVs */
grouping tlv132-ipv4-addresses {
leaf-list ipv4-addresses {
type inet:ipv4-address;
description
"List of IPv4 addresses of the IS-IS node. The IS-IS
reference is TLV 132.";
}
description
"Grouping for TLV 132.";
}
grouping tlv232-ipv6-addresses {
leaf-list ipv6-addresses {
type inet:ipv6-address;
description
"List of IPv6 addresses of the IS-IS node. The IS-IS
reference is TLV 232.";
}
description
"Grouping for TLV 232.";
}
grouping tlv134-ipv4-te-rid {
leaf ipv4-te-routerid {
type inet:ipv4-address;
description
"IPv4 Traffic Engineering router ID of the IS-IS node.
The IS-IS reference is TLV 134.";
}
description
"Grouping for TLV 134.";
}
grouping tlv140-ipv6-te-rid {
leaf ipv6-te-routerid {
type inet:ipv6-address;
description
"IPv6 Traffic Engineering router ID of the IS-IS node.
The IS-IS reference is TLV 140.";
}
description
"Grouping for TLV 140.";
}
grouping tlv129-protocols {
leaf-list protocol-supported {
type uint8;
description
"List of supported protocols of the IS-IS node.
The IS-IS reference is TLV 129.";
}
description
"Grouping for TLV 129.";
}
grouping tlv137-hostname {
leaf dynamic-hostname {
type string;
description
"Hostname of the IS-IS node. The IS-IS reference
is TLV 137.";
}
description
"Grouping for TLV 137.";
}more of the module is coming next, so stay tuned, bestie 🧚💖
grouping tlv10-authentication {
container authentication {
leaf authentication-type {
type identityref {
base key-chain:crypto-algorithm;
}
description
"Authentication type to be used with an IS-IS node.";
}
leaf authentication-key {
type string;
description
"Authentication key to be used. For security reasons,
the authentication key MUST NOT be presented in
a cleartext format in response to any request
(e.g., via get or get-config).";
}
description
"IS-IS node authentication information container. The
IS-IS reference is TLV 10.";
}
description
"Grouping for TLV 10.";
}okay so the authentication grouping is where things get serious bestie 🔐 It's giving "keep your secrets secret." The authentication-key leaf has a MUST NOT in it: the key must NOT be shown in cleartext in any response to a get or get-config request. Non-negotiable, no cap 🙅♀️
grouping tlv229-mt {
container mt-entries {
list topology {
description
"List of topologies supported.";
leaf mt-id {
type uint16 {
range "0 .. 4095";
}
description
"Multi-Topology (MT) identifier of the topology.";
}
container attributes {
leaf-list flags {
type identityref {
base tlv229-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"TLV 229 flags.";
}
}
description
"IS-IS node topology information container. The
IS-IS reference is TLV 229.";
}
description
"Grouping for TLV 229.";
}
grouping tlv242-router-capabilities {
container router-capabilities {
list router-capability {
container flags {
leaf-list router-capability-flags {
type identityref {
base router-capability-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"Router Capability flags.";
}
container node-tags {
if-feature "node-tag";
list node-tag {
leaf tag {
type uint32;
description
"Node tag value.";
}
description
"List of tags.";
}
description
"Container for node administrative tags.";
}
uses unknown-tlvs;
description
"IS-IS node capabilities. This list element may
be extended with detailed information. The IS-IS
reference is TLV 242.";
}
description
"List of Router Capability TLVs.";
}
description
"Grouping for TLV 242.";
}next up: TLV 229 is the multi-topology one 🗺️ It's a list of topology entries, each with an mt-id capped at 0 .. 4095 (uint16), plus a bunch of flags as identityrefs. Then TLV 242 is the router capabilities one 🧠 It holds a list of router-capability entries, each with its own flags, an optional node-tags container that only shows up if the node-tag feature is turned on (bestie, feature flags are like VIP passes 🎟️), and unknown-tlvs. The description literally calls it an extensible list element, which is so iconic 🦋
grouping tlv138-srlg {
description
"Grouping for TLV 138.";
container links-srlgs {
list links {
leaf neighbor-id {
type extended-system-id;
description
"System ID of the extended neighbor.";
}
leaf flags {
type uint8;
description
"Flags associated with the link.";
}
leaf link-local-id {
type union {
type inet:ip-address;
type uint32;
}
description
"Local identifier of the link.
It could be an IPv4 address or a local identifier.";
}
leaf link-remote-id {
type union {
type inet:ip-address;
type uint32;
}
description
"Remote identifier of the link.
It could be an IPv4 address or a remotely learned
identifier.";
}
container srlgs {
description
"List of SRLGs.";
leaf-list srlg {
type uint32;
description
"SRLG value of the link.";
}
}
description
"SRLG attribute of a link.";
}
description
"List of links with SRLGs.";
}
}
/* Grouping for LSDB descriptions */
grouping lsp-entry {
description
"IS-IS LSP database entry grouping.";
leaf decoded-completed {
type boolean;
description
"The IS-IS LSP body has been fully decoded.";
}
leaf raw-data {
type yang:hex-string;
description
"The hexadecimal representation of the complete LSP
as received or originated, in network byte order.";
}
leaf lsp-id {
type lsp-id;
description
"LSP ID of the LSP.";
}
leaf checksum {
type uint16;
description
"LSP checksum.";
}
leaf remaining-lifetime {
type uint16;
units "seconds";
description
"Remaining lifetime (in seconds) until LSP expiration.";
}
leaf sequence {
type uint32;
description
"This leaf describes the sequence number of the LSP.";
}
container attributes {
leaf-list lsp-flags {
type identityref {
base lsp-flag;
}
description
"This list contains identities for the bits that
are set.";
}
description
"LSP attributes.";
}
uses tlv132-ipv4-addresses;
uses tlv232-ipv6-addresses;
uses tlv134-ipv4-te-rid;
uses tlv140-ipv6-te-rid;
uses tlv129-protocols;
uses tlv137-hostname;
uses tlv10-authentication;
uses tlv229-mt;
uses tlv242-router-capabilities;
uses tlv138-srlg;
uses unknown-tlvs;
container is-neighbor {
list neighbor {
key "neighbor-id";
uses neighbor;
description
"List of neighbors.";
}
description
"Standard IS neighbors container. The IS-IS reference is
TLV 2.";
}
container extended-is-neighbor {
list neighbor {
key "neighbor-id";
uses neighbor-extended;
description
"List of extended IS neighbors.";
}
description
"Standard IS extended neighbors container. The IS-IS
reference is TLV 22.";
}
container ipv4-internal-reachability {
list prefixes {
uses prefix-ipv4-std;
description
"List of prefixes.";
}
description
"IPv4 internal reachability information container.
The IS-IS reference is TLV 128.";
}
container ipv4-external-reachability {
list prefixes {
uses prefix-ipv4-std;
description
"List of prefixes.";
}
description
"IPv4 external reachability information container. The
IS-IS reference is TLV 130.";
}
container extended-ipv4-reachability {
list prefixes {
uses prefix-ipv4-extended;
uses unknown-tlvs;
description
"List of prefixes.";
}
description
"IPv4 extended reachability information container. The
IS-IS reference is TLV 135.";
}
container mt-is-neighbor {
list neighbor {
leaf mt-id {
type uint16 {
range "0 .. 4095";
}
description
"Multi-Topology (MT) identifier.";
}
uses neighbor-extended;
description
"List of neighbors.";
}
description
"IS-IS MT neighbor container. The IS-IS reference is
TLV 223.";
}
container mt-extended-ipv4-reachability {
list prefixes {
leaf mt-id {
type uint16 {
range "0 .. 4095";
}
description
"MT identifier.";
}
uses prefix-ipv4-extended;
uses unknown-tlvs;
description
"List of extended prefixes.";
}
description
"IPv4 MT extended reachability information container.
The IS-IS reference is TLV 235.";
reference
"RFC 5120: M-ISIS: Multi Topology (MT) Routing in
Intermediate System to Intermediate Systems (IS-ISs)";
}
container mt-ipv6-reachability {
list prefixes {
leaf mt-id {
type uint16 {
range "0 .. 4095";
}
description
"MT identifier.";
}
uses prefix-ipv6-extended;
uses unknown-tlvs;
description
"List of IPv6 extended prefixes.";
}
description
"IPv6 MT extended reachability information container.
The IS-IS reference is TLV 237.";
reference
"RFC 5120: M-ISIS: Multi Topology (MT) Routing in
Intermediate System to Intermediate Systems (IS-ISs)";
}
container ipv6-reachability {
list prefixes {
uses prefix-ipv6-extended;
uses unknown-tlvs;
description
"List of IPv6 prefixes.";
}
description
"IPv6 reachability information container. The IS-IS
reference is TLV 236.";
}
}
grouping lsdb {
description
"Link State Database (LSDB) grouping.";
container database {
config false;
list levels {
key "level";
leaf level {
type level-number;
description
"LSDB level number (1 or 2).";
}
list lsp {
key "lsp-id";
uses lsp-entry;
description
"List of LSPs in the LSDB.";
}
description
"List of LSPs for the LSDB-level container.";
}
description
"IS-IS LSDB container.";
}
}
/* Augmentations */
augment "/rt:routing/"
+ "rt:ribs/rt:rib/rt:routes/rt:route" {
when "derived-from-or-self(rt:source-protocol, 'isis:isis')" {
description
"IS-IS-specific route attributes.";
}
uses route-content;
description
"This augments the route object in the Routing Information
Base (RIB) with IS-IS-specific attributes.";
}
augment "/if:interfaces/if:interface" {
leaf clns-mtu {
if-feature "osi-interface";
type uint16;
description
"Connectionless-mode Network Service (CLNS) MTU of the
interface.";
}
description
"ISO-specific interface parameters.";
}SRLG time 🌈 TLV 138 gives each link a neighbor-id, a flags uint8, and both a link-local-id and link-remote-id that can be either an IPv4 address or a uint32 (union energy 💅). Its srlgs container holds a leaf-list of uint32 srlg values.
Then comes the big LSP entry grouping 📦 It's packed with leaves: decoded-completed, raw-data (hex, in network byte order 🙈), lsp-id, checksum, remaining-lifetime in seconds, and sequence. Then it pulls in a whole pile of TLVs with uses, from TLV 132 and 232 addresses to TLV 223, 235, 237 and 236 reachability. The MT ones point back to RFC 5120 📚 as their reference.
The LSDB grouping wraps all of this in a non-config database container, with levels keyed by level (1 or 2) and an lsp list keyed by lsp-id 💜
Last bit: the augmentations. The first one adds IS-IS route attributes to the RIB route object, but only when the source protocol is isis:isis ✨ The second one adds clns-mtu to the interface, gated behind the osi-interface feature 🎀
Okay, that's the whole chunk, bestie! 🫶
okay so this is where the IS-IS augment, the RPCs and the notifications all live 🎀 the code stays exactly as written because we do NOT mess with YANG bestie 💅
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol" {
when "derived-from-or-self(rt:type, 'isis:isis')" {
description
"This augmentation is only valid when the routing protocol
instance type is 'isis'.";
}
description
"This augments a routing protocol instance with IS-IS-specific
parameters.";
container isis {
must 'count(area-address) > 0' {
error-message "At least one area address must be "
+ "configured.";
description
"Enforces the configuration of at least one area.";
}
uses instance-config;
uses instance-state;
container topologies {
if-feature "multi-topology";
list topology {
key "name";
leaf enabled {
type boolean;
description
"Enables the topology configuration.";
}
leaf name {
type leafref {
path "../../../../../../rt:ribs/rt:rib/rt:name";
}
description
"RIB corresponding to the topology.";
}
uses multi-topology-config;
description
"List of topologies.";
}
description
"MT container.";
}
container interfaces {
list interface {
key "name";
leaf name {
type if:interface-ref;
description
"Reference to the interface within
the routing instance.";
}
uses interface-config;
uses interface-state;
container topologies {
if-feature "multi-topology";
list topology {
key "name";
leaf name {
type leafref {
path "../../../../../../../../"
+ "rt:ribs/rt:rib/rt:name";
}
description
"RIB corresponding to the topology.";
}
uses multi-topology-interface-config;
description
"List of interface topologies.";
}
description
"MT container.";
}
description
"List of IS-IS interfaces.";
}
description
"Configuration container specific to IS-IS interfaces.";
}
description
"IS-IS configuration/state top-level container.";
}
}
/* RPC methods */
rpc clear-adjacency {
description
"This RPC request clears a particular set of IS-IS
adjacencies. If the operation fails for an internal
reason, then the 'error-tag' and 'error-app-tag' should be
set indicating the reason for the failure.";
reference
"RFC 6241: Network Configuration Protocol (NETCONF)";
input {
leaf routing-protocol-instance-name {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
mandatory true;
description
"Name of the IS-IS protocol instance whose IS-IS
adjacency is being cleared.
If the corresponding IS-IS instance doesn't exist,
then the operation will fail with an 'error-tag' of
'data-missing' and an 'error-app-tag' of
'routing-protocol-instance-not-found'.";
}
leaf level {
type level;
description
"IS-IS level of the adjacency to be cleared. If the
IS-IS level is 'level-all', level-1 and level-2
adjacencies would both be cleared.
If the value provided is different from the value
authorized in the enum type, then the operation
SHALL fail with an 'error-tag' of 'data-missing' and
an 'error-app-tag' of 'bad-isis-level'.";
}
leaf interface {
type if:interface-ref;
description
"IS-IS interface name.
If the corresponding IS-IS interface doesn't exist,
then the operation SHALL fail with an 'error-tag' of
'data-missing' and an 'error-app-tag' of
'isis-interface-not-found'.";
}
}
}
rpc clear-database {
description
"This RPC request clears a particular IS-IS database.
Additionally, all neighbor adjacencies will be forced to
the DOWN state and self-originated LSPs will be
reoriginated. If the operation fails for an IS-IS
internal reason, then the 'error-tag' and 'error-app-tag'
should be set indicating the reason for the failure.";
input {
leaf routing-protocol-instance-name {
type leafref {
path "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/rt:name";
}
mandatory true;
description
"Name of the IS-IS protocol instance whose IS-IS
database or databases are being cleared.
If the corresponding IS-IS instance doesn't exist,
then the operation will fail with an 'error-tag' of
'data-missing' and an 'error-app-tag' of
'routing-protocol-instance-not-found'.";
}
leaf level {
type level;
description
"IS-IS level of the adjacency to be cleared. If the
IS-IS level is 'level-all', the databases for both
level 1 and level 2 would be cleared.
If the value provided is different from the value
authorized in the enum type, then the operation
SHALL fail with an 'error-tag' of 'data-missing' and
an 'error-app-tag' of 'bad-isis-level'.";
}
}
}
/* Notifications */
notification database-overload {
uses notification-instance-hdr;
leaf overload {
type enumeration {
enum off {
description
"Indicates that the IS-IS instance has left the
overload state.";
}
enum on {
description
"Indicates that the IS-IS instance has entered the
overload state.";
}
}
description
"New overload state of the IS-IS instance.";
}
description
"This notification is sent when an IS-IS instance
overload state changes.";
}
notification lsp-too-large {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf pdu-size {
type uint32;
description
"Size of the LSP PDU.";
}
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
description
"This notification is sent when an attempt to propagate
an LSP that is larger than the dataLinkBlockSize (ISO 10589)
for the circuit occurs. The generation of the notification
must be throttled with at least 5 seconds between successive
notifications.";
reference
"ISO 10589: Intermediate System to Intermediate System
intra-domain routeing information exchange protocol
for use in conjunction with the protocol for providing
the connectionless-mode network service (ISO 8473)";
}
notification if-state-change {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf state {
type if-state-type;
description
"Interface state.";
}
description
"This notification is sent when an interface
state change is detected.";
}
notification corrupted-lsp-detected {
uses notification-instance-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
description
"This notification is sent when an LSP that was stored in
memory has become corrupted.";
}
notification attempt-to-exceed-max-sequence {
uses notification-instance-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
description
"This notification is sent when the system
wraps the 32-bit sequence counter of an LSP.";
}
notification id-len-mismatch {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf pdu-field-len {
type uint8;
description
"Value for the system ID length in the received PDU.";
}
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when a PDU with a different value
for the system ID length is received. The generation of the
notification must be throttled with at least 5 seconds
between successive notifications.";
}
notification max-area-addresses-mismatch {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf max-area-addresses {
type uint8;
description
"Received number of supported areas.";
}
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when a PDU with a different value
for the Maximum Area Addresses has been received. The
generation of the notification must be throttled with
at least 5 seconds between successive notifications.";
}
notification own-lsp-purge {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
description
"This notification is sent when the system receives
a PDU with its own system ID and zero age.";
}
notification sequence-number-skipped {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
description
"This notification is sent when the system receives a
PDU with its own system ID and different contents. The
system has to originate the LSP with a higher sequence
number.";
}
notification authentication-type-failure {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when the system receives a
PDU with the wrong authentication type field.
The generation of the notification must be throttled
with at least 5 seconds between successive notifications.";
}
notification authentication-failure {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when the system receives
a PDU on which authentication fails. The generation of the
notification must be throttled with at least 5 seconds
between successive notifications.";
} notification version-skew {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf protocol-version {
type uint8;
description
"Protocol version received in the PDU.";
}
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when the system receives a
PDU with a different protocol version number.
The generation of the notification must be throttled
with at least 5 seconds between successive notifications.";
}
notification area-mismatch {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
description
"This notification is sent when the system receives a
Hello PDU from an IS that does not share any area
address. The generation of the notification must be
throttled with at least 5 seconds between successive
notifications.";
}
notification rejected-adjacency {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
leaf reason {
type string {
length "0..255";
}
description
"The system may provide a reason to reject the
adjacency. If the reason is not available,
the reason string will not be returned.
The expected format is a single line of text.";
}
description
"This notification is sent when the system receives a
Hello PDU from an IS but does not establish an adjacency
for some reason. The generation of the notification
must be throttled with at least 5 seconds between
successive notifications.";
}
notification protocols-supported-mismatch {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
leaf-list protocols {
type uint8;
description
"List of protocols supported by the remote system.";
}
description
"This notification is sent when the system receives a
non-pseudonode LSP that has no matching protocols
supported. The generation of the notification must be
throttled with at least 5 seconds between successive
notifications.";
}
notification lsp-error-detected {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
leaf raw-pdu {
type binary;
description
"Received raw PDU.";
}
leaf error-offset {
type uint32;
description
"If the problem is a malformed TLV, the error offset
points to the start of the TLV. If the problem is with
the LSP header, the error offset points to the errant
byte.";
}
leaf tlv-type {
type uint8;
description
"If the problem is a malformed TLV, the TLV type is set
to the type value of the suspicious TLV. Otherwise,
this leaf is not present.";
}
description
"This notification is sent when the system receives an
LSP with a parse error. The generation of the notification
must be throttled with at least 5 seconds between
successive notifications.";
}
notification adjacency-state-change {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf neighbor {
type string {
length "1..255";
}
description
"Name of the neighbor. It corresponds to the hostname
associated with the system ID of the neighbor in the
mapping database (RFC 5301). If the name of the neighbor
is not available, it is not returned.";
reference
"RFC 5301: Dynamic Hostname Exchange Mechanism for IS-IS";
}
leaf neighbor-system-id {
type system-id;
description
"Neighbor system ID.";
}
leaf state {
type adj-state-type;
description
"New state of the IS-IS adjacency.";
}
leaf reason {
type string {
length "1..255";
}
description
"If the adjacency is going to the 'down' state, this leaf
provides a reason for the adjacency going down. The reason
is provided as text. If the adjacency is going to the 'up'
state, no reason is provided. The expected format is a
single line of text.";
}
description
"This notification is sent when an IS-IS adjacency
moves to the 'up' state or the 'down' state.";
}
notification lsp-received {
uses notification-instance-hdr;
uses notification-interface-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
leaf sequence {
type uint32;
description
"Sequence number of the received LSP.";
}
leaf received-timestamp {
type yang:timestamp;
description
"Timestamp when the LSP was received.";
}
leaf neighbor-system-id {
type system-id;
description
"Neighbor system ID of the LSP sender.";
}
description
"This notification is sent when an LSP is received.
The generation of the notification must be throttled with
at least 5 seconds between successive notifications.";
}
notification lsp-generation {
uses notification-instance-hdr;
leaf lsp-id {
type lsp-id;
description
"LSP ID.";
}
leaf sequence {
type uint32;
description
"Sequence number of the received LSP.";
}
leaf send-timestamp {
type yang:timestamp;
description
"Timestamp when the LSP was regenerated.";
}
description
"This notification is sent when an LSP is regenerated.
The generation of the notification must be throttled with
at least 5 seconds between successive notifications.";
}
}
<CODE ENDS>7. Security Considerations 🛡️
okay bestie, this part is SERIOUS but also kind of iconic 💅 The YANG module in this doc defines a schema for data that's meant to be reached through network management protocols like NETCONF [RFC6241] or RESTCONF [RFC8040]. For NETCONF, the bottom layer is the secure transport layer, and the one every implementation has to support is Secure Shell (SSH) [RFC6242]. For RESTCONF, the bottom layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC8446]. Locked-down vibes only 🔒✨
The Network Configuration Access Control Model (NACM) [RFC8341] lets you restrict particular NETCONF or RESTCONF users to a preset subset of the protocol operations and content. Think of it as the bouncer for your data 🚪💖
Now the spicy part 🌶️ A bunch of data nodes in this module are writable, creatable, and deletable (that's config true, which is the default). These can be sensitive or vulnerable in some network environments. If someone writes to them (like with edit-config) without proper protection, it can really mess up network operations. These are the subtrees and data nodes, plus their sensitivity and vulnerability:
/isis
/isis/interfaces/interface[name]For IS-IS, if someone can change the IS-IS configuration, they can compromise the entire IS-IS domain. They could form adjacencies with unauthorized routers to misroute traffic, or mount a massive Denial-of-Service (DoS) attack 😭 For example, adding IS-IS on any unprotected interface could let an unauthorized and malicious neighbor form an adjacency. Once that adjacency exists, traffic could be hijacked. A simpler example: a DoS attack could be mounted by making the cost of an IS-IS interface asymmetric, which could cause a hard routing loop 🔁💀 In general, unauthorized changes to most IS-IS features come with their own set of security risks, so the Security Considerations sections in the respective reference RFCs should be consulted 📚
Some of the readable data nodes in this module can also be sensitive or vulnerable, so it's important to control read access to them (for example, via get, get-config, or notification). These are the subtrees and data nodes, plus their sensitivity and vulnerability:
/isis/database
/isis/local-ribExposing the Link State Database (LSDB) reveals the detailed topology of the network 👀 The IS-IS local RIB shows the reachable prefixes in the IS-IS routing domain. Exposure of the LSDB and local RIB may also reveal information beyond the scope of the IS-IS router, which may be undesirable because it could make other attacks easier. The complete IP network topology can be rebuilt from the LSDB, and if it's deployed, so can the TE topology of the IS-IS domain. The local RIB isn't as straightforward, but it can still be exploited to discover topological information. Network operators may consider their topologies to be sensitive confidential data, and honestly, same 🫶
For IS-IS authentication, configuration is supported through a key chain [RFC8177] or through directly specifying a key and authentication algorithm. So authentication configuration using the "key-chain" case in the "authentication-type" container inherits the security considerations of [RFC8177]. This includes considerations about how authentication keys are stored and handled locally 🔑
Some of the RPC operations in this module can also be sensitive or vulnerable, so it's important to control access to them. These are the operations and their sensitivity and vulnerability:
The IS-IS YANG module supports the "clear-adjacency" and "clear-database" RPCs. If access to either one is compromised, they can be exploited to mount DoS attacks because of the resulting network outages 🙈
The actual authentication key data, whether it's locally specified or part of a key chain, is sensitive and needs to stay secret from unauthorized parties. If the key data is compromised, an attacker could forge IS-IS traffic that gets accepted as authentic, which could compromise the entire IS-IS domain. Main character villain arc, no thank you 😤
The model describes several notifications. Implementations must rate-limit the generation of these notifications to avoid creating a significant notification load. Otherwise, that load may hurt system stability and could be exploited as an attack vector 🚨
8. IANA Considerations 🧚
The IANA has assigned the following URI in the "IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-isis
Registrant Contact: The IESG
XML: N/A; the requested URI is an XML namespace.This document also adds the following YANG module name to the "YANG Module Names" registry [RFC6020]:
Name: ietf-isis
Maintained by IANA? N
Namespace: urn:ietf:params:xml:ns:yang:ietf-isis
Prefix: isis
Reference: RFC 91309. References 🌸
9.1. Normative References ✨
okay bestie, these are the normative refs 🫶 they're the stuff you NEED to know to get the whole picture 💅
[ISO-10589]
ISO, "Intermediate System to Intermediate System intra-
domain routeing information exchange protocol for use in
conjunction with the protocol for providing the
connectionless-mode network service (ISO 8473)",
International Standard 10589: 2002, Second Edition, 2002,
<https://www.iso.org/standard/30932.html>.
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
dual environments", RFC 1195, DOI 10.17487/RFC1195,
December 1990, <https://www.rfc-editor.org/info/rfc1195>.
[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>.
[RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
DOI 10.17487/RFC4090, May 2005,
<https://www.rfc-editor.org/info/rfc4090>.
[RFC5029] Vasseur, JP. and S. Previdi, "Definition of an IS-IS Link
Attribute Sub-TLV", RFC 5029, DOI 10.17487/RFC5029,
September 2007, <https://www.rfc-editor.org/info/rfc5029>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>.
[RFC5130] Previdi, S., Shand, M., Ed., and C. Martin, "A Policy
Control Mechanism in IS-IS Using Administrative Tags",
RFC 5130, DOI 10.17487/RFC5130, February 2008,
<https://www.rfc-editor.org/info/rfc5130>.
[RFC5286] Atlas, A., Ed. and A. Zinin, Ed., "Basic Specification for
IP Fast Reroute: Loop-Free Alternates", RFC 5286,
DOI 10.17487/RFC5286, September 2008,
<https://www.rfc-editor.org/info/rfc5286>.
[RFC5301] McPherson, D. and N. Shen, "Dynamic Hostname Exchange
Mechanism for IS-IS", RFC 5301, DOI 10.17487/RFC5301,
October 2008, <https://www.rfc-editor.org/info/rfc5301>.
[RFC5302] Li, T., Smit, H., and T. Przygienda, "Domain-Wide Prefix
Distribution with Two-Level IS-IS", RFC 5302,
DOI 10.17487/RFC5302, October 2008,
<https://www.rfc-editor.org/info/rfc5302>.
[RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic
Engineering", RFC 5305, DOI 10.17487/RFC5305, October
2008, <https://www.rfc-editor.org/info/rfc5305>.
[RFC5307] Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions
in Support of Generalized Multi-Protocol Label Switching
(GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008,
<https://www.rfc-editor.org/info/rfc5307>.
[RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308,
DOI 10.17487/RFC5308, October 2008,
<https://www.rfc-editor.org/info/rfc5308>.
[RFC5443] Jork, M., Atlas, A., and L. Fang, "LDP IGP
Synchronization", RFC 5443, DOI 10.17487/RFC5443, March
2009, <https://www.rfc-editor.org/info/rfc5443>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<https://www.rfc-editor.org/info/rfc5880>.
[RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
DOI 10.17487/RFC5881, June 2010,
<https://www.rfc-editor.org/info/rfc5881>.
[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>.
[RFC6119] Harrison, J., Berger, J., and M. Bartlett, "IPv6 Traffic
Engineering in IS-IS", RFC 6119, DOI 10.17487/RFC6119,
February 2011, <https://www.rfc-editor.org/info/rfc6119>.
[RFC6232] Wei, F., Qin, Y., Li, Z., Li, T., and J. Dong, "Purge
Originator Identification TLV for IS-IS", RFC 6232,
DOI 10.17487/RFC6232, May 2011,
<https://www.rfc-editor.org/info/rfc6232>.
[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>.
[RFC7490] Bryant, S., Filsfils, C., Previdi, S., Shand, M., and N.
So, "Remote Loop-Free Alternate (LFA) Fast Reroute (FRR)",
RFC 7490, DOI 10.17487/RFC7490, April 2015,
<https://www.rfc-editor.org/info/rfc7490>.
[RFC7794] Ginsberg, L., Ed., Decraene, B., Previdi, S., Xu, X., and
U. Chunduri, "IS-IS Prefix Attributes for Extended IPv4
and IPv6 Reachability", RFC 7794, DOI 10.17487/RFC7794,
March 2016, <https://www.rfc-editor.org/info/rfc7794>.
[RFC7917] Sarkar, P., Ed., Gredler, H., Hegde, S., Litkowski, S.,
and B. Decraene, "Advertising Node Administrative Tags in
IS-IS", RFC 7917, DOI 10.17487/RFC7917, July 2016,
<https://www.rfc-editor.org/info/rfc7917>.
[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>.
[RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions
for Advertising Router Information", RFC 7981,
DOI 10.17487/RFC7981, October 2016,
<https://www.rfc-editor.org/info/rfc7981>.
[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>.
[RFC8177] Lindem, A., Ed., Qu, Y., Yeung, D., Chen, I., and J.
Zhang, "YANG Data Model for Key Chains", RFC 8177,
DOI 10.17487/RFC8177, June 2017,
<https://www.rfc-editor.org/info/rfc8177>.
[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>.
[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>.
[RFC8405] Decraene, B., Litkowski, S., Gredler, H., Lindem, A.,
Francois, P., and C. Bowers, "Shortest Path First (SPF)
Back-Off Delay Algorithm for Link-State IGPs", RFC 8405,
DOI 10.17487/RFC8405, June 2018,
<https://www.rfc-editor.org/info/rfc8405>.
[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>.
[RFC8570] Ginsberg, L., Ed., Previdi, S., Ed., Giacalone, S., Ward,
D., Drake, J., and Q. Wu, "IS-IS Traffic Engineering (TE)
Metric Extensions", RFC 8570, DOI 10.17487/RFC8570, March
2019, <https://www.rfc-editor.org/info/rfc8570>.
[RFC8706] Ginsberg, L. and P. Wells, "Restart Signaling for IS-IS",
RFC 8706, DOI 10.17487/RFC8706, February 2020,
<https://www.rfc-editor.org/info/rfc8706>.
[RFC9314] Jethanandani, M., Ed., Rahman, R., Ed., Zheng, L., Ed.,
Pallagatti, S., and G. Mirsky, "YANG Data Model for
Bidirectional Forwarding Detection (BFD)", RFC 9314,
DOI 10.17487/RFC9314, September 2022,
<https://www.rfc-editor.org/info/rfc9314>.
[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<https://www.w3.org/TR/2008/REC-xml-20081126>.9.2. Informative References 🧚
and these are the informative ones, which are good to know about but aren't strictly needed to implement the spec 🌸
[RFC7812] Atlas, A., Bowers, C., and G. Enyedi, "An Architecture for
IP/LDP Fast Reroute Using Maximally Redundant Trees (MRT-
FRR)", RFC 7812, DOI 10.17487/RFC7812, June 2016,
<https://www.rfc-editor.org/info/rfc7812>.
[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>.
[SR-TI-LFA]
Litkowski, S., Bashandy, A., Filsfils, C., Francois, P.,
Decraene, B., and D. Voyer, "Topology Independent Fast
Reroute using Segment Routing", Work in Progress,
Internet-Draft, draft-ietf-rtgwg-segment-routing-ti-lfa-
08, 21 January 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-rtgwg-
segment-routing-ti-lfa-08>.Appendix A. Example of IS-IS Configuration in XML ✨
okay bestie, this appendix is the fun part 🎀 it shows what an IS-IS instance config looks like on a device, written in XML [W3C.REC-xml-20081126]. the root is a NETCONF data element, and the routing, IS-IS, and interface bits all nest inside it 🦋
<?xml version="1.0" encoding="utf-8"?>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<name>SLI</name>
<router-id>192.0.2.1</router-id>
<control-plane-protocols>
<control-plane-protocol>
<name>IS-IS-example</name>
<description/>
<type>
<type xmlns:isis="urn:ietf:params:xml:ns:yang:ietf-isis">
isis:isis
</type>
</type>
<isis xmlns="urn:ietf:params:xml:ns:yang:ietf-isis">
<enabled>true</enabled>
<level-type>level-2</level-type>
<system-id>87FC.FCDF.4432</system-id>
<area-address>49.0001</area-address>
<mpls>
<te-rid>
<ipv4-router-id>192.0.2.1</ipv4-router-id>
</te-rid>
</mpls>
<lsp-lifetime>65535</lsp-lifetime>
<lsp-refresh>65000</lsp-refresh>
<metric-type>
<value>wide-only</value>
</metric-type>
<default-metric>
<value>111111</value>
</default-metric>
<address-families>
<address-family-list>
<address-family>ipv4</address-family>
<enabled>true</enabled>
</address-family-list>
<address-family-list>
<address-family>ipv6</address-family>
<enabled>true</enabled>
</address-family-list>
</address-families>
<interfaces>
<interface>
<name>Loopback0</name>
<tag>200</tag>
<metric>
<value>0</value>
</metric>
<passive>true</passive>
</interface>
<interface>
<name>Eth1</name>
<level-type>level-2</level-type>
<interface-type>point-to-point</interface-type>
<metric>
<value>167890</value>
</metric>
</interface>
</interfaces>
</isis>
</control-plane-protocol>
</control-plane-protocols>
</routing>
<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface>
<name>Loopback0</name>
<description/>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
ianaift:softwareLoopback
</type>
<link-up-down-trap-enable>enabled</link-up-down-trap-enable>
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>192.0.2.1</ip>
<prefix-length>32</prefix-length>
</address>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>2001:db8::1</ip>
<prefix-length>128</prefix-length>
</address>
</ipv6>
</interface>
<interface>
<name>Eth1</name>
<description/>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
ianaift:ethernetCsmacd
</type>
<link-up-down-trap-enable>enabled</link-up-down-trap-enable>
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>198.51.100.1</ip>
<prefix-length>30</prefix-length>
</address>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>2001:db8:0:0:ff::1</ip>
<prefix-length>64</prefix-length>
</address>
</ipv6>
</interface>
</interfaces>
</data>Acknowledgments 💜
the authors would like to thank Tom Petch, Alvaro Retana, Stewart Bryant, Barry Leiba, Benjamin Kaduk, Adam Roach, and Roman Danyliw for their review and comments 🫶
Contributors 🌸
the authors would like to thank Kiran Agrahara Sreenivasa, Dean Bogdanovic, Yingzhen Qu, Yi Yang, and Jeff Tantsura for their major contributions to this document 👑
Authors' Addresses 💅
Stephane Litkowski (editor) Cisco Systems Email: slitkows.ietf@gmail.com
Derek Yeung Arrcus, Inc. 2077 Gateway Place, Suite 400 San Jose, CA 95110 United States of America Email: derek@arrcus.com
Acee Lindem Cisco Systems 301 Midenhall Way Cary, NC 27513 United States of America Email: acee@cisco.com
Jeffrey Zhang Juniper Networks 10 Technology Park Drive Westford, MA 01886 United States of America Email: zzhang@juniper.net
Ladislav Lhotka CZ.NIC Email: ladislav.lhotka@nic.cz
that's the whole doc, bestie 🌈✨ the authors really cooked, periodt 💖
📦 where this page comes from
- ietf: rfc9130 2022-10
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms