Internet Assigned Numbers Authority Interior Gateway Protocol (IGP) Parameters Created 2017-12-18 Last Updated 2024-04-17 Available Formats [IMG] XML [IMG] HTML [IMG] Plain text Registries included below • IGP Algorithm Types • IGP MSD-Types • Link Attribute Application Identifiers • IGP Metric-Type • IGP Flexible Algorithm Definition Flags • Path Computation Element (PCE) Capability Flags • PCE Discovery (PCED) Sub-TLV Type Indicators • IGP Algorithm Type For Computing Flooding Topology IGP Algorithm Types Registration Procedure(s) Standards Action Reference [RFC8665] Available Formats [IMG] CSV Value Description Reference Shortest Path First (SPF) algorithm based on link metric. This is the standard shortest path algorithm as computed 0 by the IGP protocol. Consistent with the deployed practice for link-state protocols, Algorithm 0 permits any node [RFC8665] to overwrite the SPF path with a different path based on its local policy. Strict Shortest Path First (SPF) algorithm based on link metric. The algorithm is identical to Algorithm 0 but 1 Algorithm 1 requires that all nodes along the path will honor the SPF routing decision. Local policy at the node [RFC8665] claiming support for Algorithm 1 MUST NOT alter the SPF paths computed by Algorithm 1. 2-127 Unassigned 128-255 Flexible Algorithms [RFC9350, Section 4] IGP MSD-Types Registration Procedure(s) Expert Review Expert(s) Uma Chunduri, Jeff Tantsura Reference [RFC8491] Available Formats [IMG] CSV Value Name Reference 0 Reserved [RFC8491] 1 Base MPLS Imposition MSD [RFC8491] 2 ERLD-MSD [RFC9088] 3-40 Unassigned 41 SRH Max SL [RFC9352] 42 SRH Max End Pop [RFC9352] 43 Unassigned 44 SRH Max H.encaps [RFC9352] 45 SRH Max End D [RFC9352] 46-250 Unassigned 251-254 Experimental Use [RFC8491] 255 Reserved [RFC8491] Link Attribute Application Identifiers Registration Procedure(s) Expert Review Expert(s) Les Ginsberg, Chris Hopps Reference [RFC9479] Available Formats [IMG] CSV Bit Name Reference 0 RSVP-TE (R-bit) [RFC9479] 1 Segment Routing Policy (S-bit) [RFC9479] 2 Loop-Free Alternate (F-bit) [RFC9479] 3 Flexible Algorithm (X-bit) [RFC9350, Section 12] 4-63 Unassigned IGP Metric-Type Registration Procedure(s) Standards Action Reference [RFC9350] Available Formats [IMG] CSV Type Description Reference 0 IGP Metric [RFC9350, Section 5.1] 1 Min Unidirectional Link Delay as defined in [RFC8570, Section 4.2] and [RFC7471, Section 4.2] [RFC9350, Section 5.1] 2 Traffic Engineering Default Metric as defined in [RFC5305, Section 3.7] and Traffic Engineering [RFC9350, Section 5.1] Metric as defined in [RFC3630, Section 2.5.5] 3 Bandwidth Metric (TEMPORARY - registered 2023-02-10, extension registered 2023-12-21, expires [draft-ietf-lsr-flex-algo-bw-con-07] 2025-02-10) 4-255 Unassigned IGP Flexible Algorithm Definition Flags Registration Procedure(s) Standards Action Reference [RFC9350] Available Formats [IMG] CSV Bit Name Reference 0 Prefix Metric Flag (M-flag) [RFC9350, Sections 6.4 and 7.4] Path Computation Element (PCE) Capability Flags Registration Procedure(s) IETF Review Reference [RFC9353] Available Formats [IMG] CSV Bit Capability Description Reference 0 Path computation with GMPLS link constraints [RFC5088] 1 Bidirectional path computation [RFC5088] 2 Diverse path computation [RFC5088] 3 Load-balanced path computation [RFC5088] 4 Synchronized paths computation [RFC5088] 5 Support for multiple objective functions [RFC5088] 6 Support for additive path constraints (max hop count, etc.) [RFC5088] 7 Support for request prioritization [RFC5088] 8 Support for multiple requests per message [RFC5088] 9 Global Concurrent Optimization (GCO) [RFC5557] 10 P2MP path computation [RFC8306] 11 Active stateful PCE capability [RFC8231] 12 Passive stateful PCE capability [RFC8231] 13 Active Stateful PCE with P2MP [RFC8623] 14 Passive Stateful PCE with P2MP [RFC8623] 15 Stateful PCE Initiation with P2MP [RFC8623] 16 FlowSpec [RFC9168] 17 TCP-AO Support [RFC9353] 18 PCEP over TLS support [RFC9353] 19-31 Unassigned PCE Discovery (PCED) Sub-TLV Type Indicators Registration Procedure(s) Standards Action Reference [RFC9353] Available Formats [IMG] CSV Value Description Reference 0 Reserved [RFC9353][RFC5088] 1 PCE-ADDRESS [RFC9353][RFC5088] 2 PATH-SCOPE [RFC9353][RFC5088] 3 PCE-DOMAIN [RFC9353][RFC5088] 4 NEIG-PCE-DOMAIN [RFC9353][RFC5088] 5 PCE-CAP-FLAGS [RFC9353][RFC5088] 6 KEY-ID [RFC9353] 7 KEY-CHAIN-NAME [RFC9353] 8-65535 Unassigned IGP Algorithm Type For Computing Flooding Topology Registration Procedure(s) Expert Review Expert(s) Unassigned Reference [RFC-ietf-lsr-dynamic-flooding-18] Available Formats [IMG] CSV Value Description Reference 0 Reserved for centralized mode [RFC-ietf-lsr-dynamic-flooding-18] 1-127 Unassigned 128-254 Reserved for Private Use [RFC-ietf-lsr-dynamic-flooding-18] 255 Reserved [RFC-ietf-lsr-dynamic-flooding-18] Licensing Terms