Interior Gateway Protocol (IGP) Parameters
- Created
- 2017-12-18
- Last Updated
- 2024-04-17
- Available Formats
-

XML
HTML
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
-

CSV
| Value | Description | Reference |
|---|---|---|
| 0 | Shortest Path First (SPF) algorithm based on link metric. This is the standard shortest path algorithm as computed by the IGP protocol. Consistent with the deployed practice for link-state protocols, Algorithm 0 permits any node to overwrite the SPF path with a different path based on its local policy. | [RFC8665] |
| 1 | Strict Shortest Path First (SPF) algorithm based on link metric. The algorithm is identical to Algorithm 0 but Algorithm 1 requires that all nodes along the path will honor the SPF routing decision. Local policy at the node claiming support for Algorithm 1 MUST NOT alter the SPF paths computed by Algorithm 1. | [RFC8665] |
| 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
-

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
-

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
-

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 Metric as defined in [RFC3630, Section 2.5.5] | [RFC9350, Section 5.1] |
| 3 | Bandwidth Metric (TEMPORARY - registered 2023-02-10, extension registered 2023-12-21, expires 2025-02-10) | [draft-ietf-lsr-flex-algo-bw-con-07] |
| 4-255 | Unassigned |
IGP Flexible Algorithm Definition Flags
- Registration Procedure(s)
-
Standards Action
- Reference
- [RFC9350]
- Available Formats
-

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
-

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
-

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
-

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] |