Lsr Workgroup RFCs

Browse Lsr Workgroup RFCs by Number

RFC8476 - Signaling Maximum SID Depth (MSD) Using OSPF: This document defines a way for an Open Shortest Path First (OSPF) router to advertise multiple types of supported Maximum SID Depths (MSDs) at node and/or link granularity. Such advertisements allow entities (e.g., centralized controllers) to determine whether a particular Segment Identifier (SID) stack can be supported in a given network. This document only refers to the Signaling MSD as defined in RFC 8491, but it defines an encoding that can support other MSD types. Here, the term "OSPF" means both OSPFv2 and OSPFv3.
RFC8491 - Signaling Maximum SID Depth (MSD) Using IS-IS: This document defines a way for an Intermediate System to Intermediate System (IS-IS) router to advertise multiple types of supported Maximum SID Depths (MSDs) at node and/or link granularity. Such advertisements allow entities (e.g., centralized controllers) to determine whether a particular Segment ID (SID) stack can be supported in a given network. This document only defines one type of MSD: Base MPLS Imposition. However, it defines an encoding that can support other MSD types. This document focuses on MSD use in a network that is Segment Routing (SR) enabled, but MSD may also be useful when SR is not enabled.
RFC8500 - IS-IS Routing with Reverse Metric: This document describes a mechanism to allow IS-IS routing to quickly and accurately shift traffic away from either a point-to-point or multi-access LAN interface during network maintenance or other operational events. This is accomplished by signaling adjacent IS-IS neighbors with a higher reverse metric, i.e., the metric towards the signaling IS-IS router.
RFC8510 - OSPF Link-Local Signaling (LLS) Extensions for Local Interface ID Advertisement: Every OSPF interface is assigned an Interface ID that uniquely identifies the interface on the router. In some cases, it is useful to know the assigned Interface ID on the remote side of the adjacency (Remote Interface ID).; This document describes the extensions to OSPF link-local signaling (LLS) to advertise the Local Interface ID.
RFC8570 - IS-IS Traffic Engineering (TE) Metric Extensions: In certain networks, such as, but not limited to, financial information networks (e.g., stock market data providers), network-performance criteria (e.g., latency) are becoming as critical to data-path selection as other metrics.; This document describes extensions to IS-IS Traffic Engineering Extensions (RFC 5305). These extensions provide a way to distribute and collect network-performance information in a scalable fashion. The information distributed using IS-IS TE Metric Extensions can then be used to make path-selection decisions based on network performance.; Note that this document only covers the mechanisms with which network-performance information is distributed. The mechanisms for measuring network performance or acting on that information, once distributed, are outside the scope of this document.; This document obsoletes RFC 7810.
RFC8666 - OSPFv3 Extensions for Segment Routing: Segment Routing (SR) allows a flexible definition of end-to-end paths within IGP topologies by encoding paths as sequences of topological subpaths called "segments". These segments are advertised by the link-state routing protocols (IS-IS and OSPF).; This document describes the OSPFv3 extensions required for Segment Routing with the MPLS data plane.
RFC8667 - IS-IS Extensions for Segment Routing: Segment Routing (SR) allows for a flexible definition of end-to-end paths within IGP topologies by encoding paths as sequences of topological sub-paths, called "segments". These segments are advertised by the link-state routing protocols (IS-IS and OSPF).; This document describes the IS-IS extensions that need to be introduced for Segment Routing operating on an MPLS data plane.
RFC8687 - OSPF Routing with Cross-Address Family Traffic Engineering Tunnels: When using Traffic Engineering (TE) in a dual-stack IPv4/IPv6 network, the Multiprotocol Label Switching (MPLS) TE Label Switched Path (LSP) infrastructure may be duplicated, even if the destination IPv4 and IPv6 addresses belong to the same remote router. In order to achieve an integrated MPLS TE LSP infrastructure, OSPF routes must be computed over MPLS TE tunnels created using information propagated in another OSPF instance. This issue is solved by advertising cross-address family (X-AF) OSPF TE information.; This document describes an update to RFC 5786 that allows for the easy identification of a router's local X-AF IP addresses.
RFC8706 - Restart Signaling for IS-IS: This document describes a mechanism for a restarting router to signal to its neighbors that it is restarting, allowing them to reestablish their adjacencies without cycling through the DOWN state while still correctly initiating database synchronization.; This document additionally describes a mechanism for a router to signal its neighbors that it is preparing to initiate a restart while maintaining forwarding-plane state. This allows the neighbors to maintain their adjacencies until the router has restarted but also allows the neighbors to bring the adjacencies down in the event of other topology changes.; This document additionally describes a mechanism for a restarting router to determine when it has achieved Link State Protocol Data Unit (LSP) database synchronization with its neighbors and a mechanism to optimize LSP database synchronization while minimizing transient routing disruption when a router starts.; This document obsoletes RFC 5306.
RFC8770 - Host Router Support for OSPFv2: The Open Shortest Path First Version 2 (OSPFv2) protocol does not have a mechanism for a node to repel transit traffic if it is on the shortest path. This document defines a bit called the Host-bit (H-bit). This bit enables a router to advertise that it is a non-transit router. This document also describes the changes needed to support the H-bit in the domain. In addition, this document updates RFC 6987 to advertise Type 2 External and Not-So-Stubby Area (NSSA) Link State Advertisements (LSAs) (RFC 3101) with a high cost in order to repel traffic effectively.
RFC8918 - Invalid TLV Handling in IS-IS: The key to the extensibility of the Intermediate System to Intermediate System (IS-IS) protocol has been the handling of unsupported and/or invalid Type-Length-Value (TLV) tuples. Although there are explicit statements in existing specifications, deployment experience has shown that there are inconsistencies in the behavior when a TLV that is disallowed in a particular Protocol Data Unit (PDU) is received.; This document discusses such cases and makes the correct behavior explicit in order to ensure that interoperability is maximized.; This document updates RFCs 5305 and 6232.
RFC8919 - IS-IS Application-Specific Link Attributes: Existing traffic-engineering-related link attribute advertisements have been defined and are used in RSVP-TE deployments. Since the original RSVP-TE use case was defined, additional applications (e.g., Segment Routing Policy and Loop-Free Alternates) that also make use of the link attribute advertisements have been defined. In cases where multiple applications wish to make use of these link attributes, the current advertisements do not support application-specific values for a given attribute, nor do they support indication of which applications are using the advertised value for a given link. This document introduces new link attribute advertisements that address both of these shortcomings.
RFC8920 - OSPF Application-Specific Link Attributes: Existing traffic-engineering-related link attribute advertisements have been defined and are used in RSVP-TE deployments. Since the original RSVP-TE use case was defined, additional applications (e.g., Segment Routing Policy and Loop-Free Alternates) that also make use of the link attribute advertisements have been defined. In cases where multiple applications wish to make use of these link attributes, the current advertisements do not support application-specific values for a given attribute, nor do they support indication of which applications are using the advertised value for a given link. This document introduces new link attribute advertisements in OSPFv2 and OSPFv3 that address both of these shortcomings.
RFC9084 - OSPF Prefix Originator Extensions: This document defines OSPF extensions to include information associated with the node originating a prefix along with the prefix advertisement. These extensions do not change the core OSPF route computation functionality but provide useful information for network analysis, troubleshooting, and use cases like traffic engineering.
RFC9088 - Signaling Entropy Label Capability and Entropy Readable Label Depth Using IS-IS: Multiprotocol Label Switching (MPLS) has defined a mechanism to load-balance traffic flows using Entropy Labels (EL). An ingress Label Switching Router (LSR) cannot insert ELs for packets going into a given Label Switched Path (LSP) unless an egress LSR has indicated via signaling that it has the capability to process ELs, referred to as the Entropy Label Capability (ELC), on that LSP. In addition, it would be useful for ingress LSRs to know each LSR's capability for reading the maximum label stack depth and performing EL-based load-balancing, referred to as Entropy Readable Label Depth (ERLD). This document defines a mechanism to signal these two capabilities using IS-IS and Border Gateway Protocol - Link State (BGP-LS).
RFC9089 - Signaling Entropy Label Capability and Entropy Readable Label Depth Using OSPF: Multiprotocol Label Switching (MPLS) has defined a mechanism to load-balance traffic flows using Entropy Labels (EL). An ingress Label Switching Router (LSR) cannot insert ELs for packets going into a given Label Switched Path (LSP) unless an egress LSR has indicated via signaling that it has the capability to process ELs, referred to as the Entropy Label Capability (ELC), on that LSP. In addition, it would be useful for ingress LSRs to know each LSR's capability for reading the maximum label stack depth and performing EL-based load-balancing, referred to as Entropy Readable Label Depth (ERLD). This document defines a mechanism to signal these two capabilities using OSPFv2 and OSPFv3, and Border Gateway Protocol - Link State (BGP-LS).
RFC9129 - YANG Data Model for the OSPF Protocol: This document defines a YANG data model that can be used to configure and manage OSPF. The model is based on YANG 1.1 as defined in RFC 7950 and conforms to the Network Management Datastore Architecture (NMDA) as described in RFC 8342.
RFC9130 - YANG Data Model for the IS-IS Protocol: This document defines a YANG data model that can be used to configure and manage the IS-IS protocol on network elements.
RFC9194 - A YANG Module for IS-IS Reverse Metric: This document defines a YANG module for managing the reverse metric extension to the Intermediate System to Intermediate System (IS-IS) intra-domain routing information exchange protocol.
RFC9339 - OSPF Reverse Metric: This document specifies the extensions to OSPF that enable a router to use Link-Local Signaling (LLS) to signal the metric that receiving OSPF neighbor(s) should use for a link to the signaling router. When used on the link to the signaling router, the signaling of this reverse metric (RM) allows a router to influence the amount of traffic flowing towards itself. In certain use cases, this enables routers to maintain symmetric metrics on both sides of a link between them.
RFC9346 - IS-IS Extensions in Support of Inter-Autonomous System (AS) MPLS and GMPLS Traffic Engineering: This document describes extensions to the Intermediate System to Intermediate System (IS-IS) protocol to support Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS) Traffic Engineering (TE) for multiple Autonomous Systems (ASes). It defines IS-IS extensions for the flooding of TE information about inter-AS links, which can be used to perform inter-AS TE path computation.; No support for flooding information from within one AS to another AS is proposed or defined in this document.; This document builds on RFC 5316 by adding support for IPv6-only operation.; This document obsoletes RFC 5316.
RFC9350 - IGP Flexible Algorithm: IGP protocols historically compute the best paths over the network based on the IGP metric assigned to the links. Many network deployments use RSVP-TE or Segment Routing - Traffic Engineering (SR-TE) to steer traffic over a path that is computed using different metrics or constraints than the shortest IGP path. This document specifies a solution that allows IGPs themselves to compute constraint-based paths over the network. This document also specifies a way of using Segment Routing (SR) Prefix-SIDs and SRv6 locators to steer packets along the constraint-based paths.
RFC9352 - IS-IS Extensions to Support Segment Routing over the IPv6 Data Plane: The Segment Routing (SR) architecture allows a flexible definition of the end-to-end path by encoding it as a sequence of topological elements called "segments". It can be implemented over the MPLS or the IPv6 data plane. This document describes the IS-IS extensions required to support SR over the IPv6 data plane.; This document updates RFC 7370 by modifying an existing registry.
RFC9353 - IGP Extension for Path Computation Element Communication Protocol (PCEP) Security Capability Support in PCE Discovery (PCED): When a Path Computation Element (PCE) is a Label Switching Router (LSR) or a server participating in the Interior Gateway Protocol (IGP), its presence and path computation capabilities can be advertised using IGP flooding. The IGP extensions for PCE Discovery (PCED) (RFCs 5088 and 5089) define a method to advertise path computation capabilities using IGP flooding for OSPF and IS-IS, respectively. However, these specifications lack a method to advertise Path Computation Element Communication Protocol (PCEP) security (e.g., Transport Layer Security (TLS) and TCP Authentication Option (TCP-AO)) support capability.; This document defines capability flag bits for the PCE-CAP-FLAGS sub-TLV that can be announced as an attribute in the IGP advertisement to distribute PCEP security support information. In addition, this document updates RFCs 5088 and 5089 to allow advertisement of a Key ID or KEY-CHAIN-NAME sub-TLV to support TCP-AO security capability. This document also updates RFCs 8231 and 8306.
RFC9355 - OSPF Bidirectional Forwarding Detection (BFD) Strict-Mode: This document specifies the extensions to OSPF that enable an OSPF; router to signal the requirement for a Bidirectional Forwarding; Detection (BFD) session prior to adjacency formation. Link-Local; Signaling (LLS) is used to advertise the requirement for strict-mode; BFD session establishment for an OSPF adjacency. If both OSPF; neighbors advertise BFD strict-mode, adjacency formation will be; blocked until a BFD session has been successfully established.; This document updates RFC 2328 by augmenting the OSPF neighbor state; machine with a check for BFD session up before progression from Init; to 2-Way state when operating in OSPF BFD strict-mode.
RFC9356 - Advertising Layer 2 Bundle Member Link Attributes in OSPF: There are deployments where the Layer 3 (L3) interface on which OSPF operates is a Layer 2 (L2) interface bundle. Existing OSPF advertisements only support advertising link attributes of the L3 interface. If entities external to OSPF wish to control traffic flows on the individual physical links that comprise the L2 interface bundle, link attribute information for the bundle members is required.; This document defines the protocol extensions for OSPF to advertise the link attributes of L2 bundle members. The document also specifies the advertisement of these OSPF extensions via the Border Gateway Protocol - Link State (BGP-LS) and thereby updates RFC 9085.
RFC9377 - IS-IS Flood Reflection: This document describes a backward-compatible, optional IS-IS extension that allows the creation of IS-IS flood reflection topologies. Flood reflection permits topologies in which IS-IS Level 1 (L1) areas provide transit-forwarding for IS-IS Level 2 (L2) areas using all available L1 nodes internally. It accomplishes this by creating L2 flood reflection adjacencies within each L1 area. Those adjacencies are used to flood L2 Link State Protocol Data Units (LSPs) and are used in the L2 Shortest Path First (SPF) computation. However, they are not ordinarily utilized for forwarding within the flood reflection cluster. This arrangement gives the L2 topology significantly better scaling properties than prevalently used flat designs. As an additional benefit, only those routers directly participating in flood reflection are required to support the feature. This allows for incremental deployment of scalable L1 transit areas in an existing, previously flat network design, without the necessity of upgrading all routers in the network.
RFC9454 - Update to OSPF Terminology: This document updates some OSPF terminology to be in line with inclusive language used in the industry. The IETF has designated "Guidance for NIST Staff on Using Inclusive Language in Documentary Standards" by the US National Institute of Standards and Technology (NIST) for its inclusive language guidelines. It is intended that all future OSPF documents use this revised terminology even when they reference the RFCs updated by this document.; This document updates RFCs 2328, 4222, 4811, 5243, 5340, 5614, and 5838.
RFC9479 - IS-IS Application-Specific Link Attributes: Existing traffic-engineering-related link attribute advertisements have been defined and are used in RSVP-TE deployments. Since the original RSVP-TE use case was defined, additional applications (e.g., Segment Routing Policy and Loop-Free Alternates) that also make use of the link attribute advertisements have been defined. In cases where multiple applications wish to make use of these link attributes, the current advertisements do not support application-specific values for a given attribute, nor do they support an indication of which applications are using the advertised value for a given link. This document introduces link attribute advertisements that address both of these shortcomings.; This document obsoletes RFC 8919.
RFC9492 - OSPF Application-Specific Link Attributes: Existing traffic-engineering-related link attribute advertisements have been defined and are used in RSVP-TE deployments. Since the original RSVP-TE use case was defined, additional applications such as Segment Routing (SR) Policy and Loop-Free Alternates (LFAs) that also make use of the link attribute advertisements have been defined. In cases where multiple applications wish to make use of these link attributes, the current advertisements do not support application-specific values for a given attribute, nor do they support indication of which applications are using the advertised value for a given link. This document introduces link attribute advertisements in OSPFv2 and OSPFv3 that address both of these shortcomings.; This document obsoletes RFC 8920.
RFC9502 - IGP Flexible Algorithm in IP Networks: This document extends IGP Flexible Algorithm so that it can be used with regular IPv4 and IPv6 forwarding.
RFC9513 - OSPFv3 Extensions for Segment Routing over IPv6 (SRv6): The Segment Routing (SR) architecture allows a flexible definition of the end-to-end path by encoding it as a sequence of topological elements called segments. It can be implemented over an MPLS or IPv6 data plane. This document describes the OSPFv3 extensions required to support SR over the IPv6 data plane.
RFC9587 - YANG Data Model for OSPFv3 Extended Link State Advertisements (LSAs): This document defines a YANG data model augmenting the IETF OSPF YANG data model (RFC 9129) to provide support for OSPFv3 Link State Advertisement (LSA) Extensibility as defined in RFC 8362. OSPFv3 Extended LSAs provide extensible TLV-based LSAs for the base LSA types defined in RFC 5340.
RFC9650 - Revision to Registration Procedures for IS-IS Neighbor Link-Attribute Bit Values: RFC 5029, "Definition of an IS-IS Link Attribute Sub-TLV", defines an IANA registry called "IS-IS Neighbor Link-Attribute Bit Values". This document changes the registration procedure for that registry from "Standards Action" to "Expert Review". This document updates RFC 5029.
RFC9666 - Area Proxy for IS-IS: Link-state routing protocols have hierarchical abstraction already built into them. However, when lower levels are used for transit, they must expose their internal topologies to each other, thereby leading to scaling issues.; To avoid such issues, this document discusses extensions to the IS-IS routing protocol that allow Level 1 (L1) areas to provide transit but only inject an abstraction of the Level 1 topology into Level 2 (L2). Each Level 1 area is represented as a single Level 2 node, thereby enabling a greater scale.
RFC9667 - Dynamic Flooding on Dense Graphs: Routing with link-state protocols in dense network topologies can result in suboptimal convergence times due to the overhead associated with flooding. This can be addressed by decreasing the flooding topology so that it is less dense.; This document discusses the problem in some depth and an architectural solution. Specific protocol changes for IS-IS, OSPFv2, and OSPFv3 are described in this document.
RFC9681 - IS-IS Fast Flooding: Current Link State PDU flooding rates are much slower than what modern networks can support. The use of IS-IS at larger scale requires faster flooding rates to achieve desired convergence goals. This document discusses the need for faster flooding, the issues around faster flooding, and some example approaches to achieve faster flooding. It also defines protocol extensions relevant to faster flooding.