| rfc9815v3.txt | rfc9815.txt | |||
|---|---|---|---|---|
| Internet Engineering Task Force (IETF) K. Patel | Internet Engineering Task Force (IETF) K. Patel | |||
| Request for Comments: 9815 A. Lindem | Request for Comments: 9815 A. Lindem | |||
| Category: Standards Track Arrcus, Inc. | Category: Standards Track Arrcus, Inc. | |||
| ISSN: 2070-1721 S. Zandi | ISSN: 2070-1721 S. Zandi | |||
| W. Henderickx | W. Henderickx | |||
| Nokia | Nokia | |||
| July 2025 | July 2025 | |||
| BGP Link-State Shortest Path First (SPF) Routing | BGP Link State (BGP-LS) Shortest Path First (SPF) Routing | |||
| Abstract | Abstract | |||
| Many Massively Scaled Data Centers (MSDCs) have converged on | Many Massively Scaled Data Centers (MSDCs) have converged on | |||
| simplified Layer 3 (L3) routing. Furthermore, requirements for | simplified Layer 3 (L3) routing. Furthermore, requirements for | |||
| operational simplicity have led many of these MSDCs to converge on | operational simplicity have led many of these MSDCs to converge on | |||
| BGP as their single routing protocol for both fabric routing and Data | BGP as their single routing protocol for both fabric routing and Data | |||
| Center Interconnect (DCI) routing. This document describes | Center Interconnect (DCI) routing. This document describes | |||
| extensions to BGP for use with BGP Link State (BGP-LS) distribution | extensions to BGP for use with BGP Link State (BGP-LS) distribution | |||
| and the Shortest Path First (SPF) algorithm. In doing this, it | and the Shortest Path First (SPF) algorithm. In doing this, it | |||
| skipping to change at line 68 ¶ | skipping to change at line 68 ¶ | |||
| 1.2. Requirements Language | 1.2. Requirements Language | |||
| 1.3. BGP Shortest Path First (SPF) Motivation | 1.3. BGP Shortest Path First (SPF) Motivation | |||
| 1.4. Document Overview | 1.4. Document Overview | |||
| 2. Base BGP Protocol Relationship | 2. Base BGP Protocol Relationship | |||
| 3. BGP Link State (BGP-LS) Relationship | 3. BGP Link State (BGP-LS) Relationship | |||
| 4. BGP SPF Peering Models | 4. BGP SPF Peering Models | |||
| 4.1. BGP Single-Hop Peering on Network Node Connections | 4.1. BGP Single-Hop Peering on Network Node Connections | |||
| 4.2. BGP Peering Between Directly Connected Nodes | 4.2. BGP Peering Between Directly Connected Nodes | |||
| 4.3. BGP Peering in Route-Reflector or Controller Topology | 4.3. BGP Peering in Route-Reflector or Controller Topology | |||
| 5. BGP Shortest Path First (SPF) Routing Protocol Extensions | 5. BGP Shortest Path First (SPF) Routing Protocol Extensions | |||
| 5.1. BGP-LS SPF SAFI | 5.1. BGP-LS-SPF SAFI | |||
| 5.1.1. BGP-LS-SPF NLRI TLVs | 5.1.1. BGP-LS-SPF NLRI TLVs | |||
| 5.1.2. BGP-LS Attribute | 5.1.2. BGP-LS Attribute | |||
| 5.2. Extensions to BGP-LS | 5.2. Extensions to BGP-LS | |||
| 5.2.1. Node NLRI Usage | 5.2.1. Node NLRI Usage | |||
| 5.2.1.1. BGP-LS-SPF Node NLRI Attribute SPF Status TLV | 5.2.1.1. BGP-LS-SPF Node NLRI Attribute SPF Status TLV | |||
| 5.2.2. Link NLRI Usage | 5.2.2. Link NLRI Usage | |||
| 5.2.2.1. BGP-LS Link NLRI Address Family Link Descriptor TLV | 5.2.2.1. BGP-LS Link NLRI Address Family Link Descriptor TLV | |||
| 5.2.2.2. BGP-LS-SPF Link NLRI Attribute SPF Status TLV | 5.2.2.2. BGP-LS-SPF Link NLRI Attribute SPF Status TLV | |||
| 5.2.3. IPv4/IPv6 Prefix NLRI Usage | 5.2.3. IPv4/IPv6 Prefix NLRI Usage | |||
| 5.2.3.1. BGP-LS-SPF Prefix NLRI Attribute SPF Status TLV | 5.2.3.1. BGP-LS-SPF Prefix NLRI Attribute SPF Status TLV | |||
| skipping to change at line 413 ¶ | skipping to change at line 413 ¶ | |||
| The controller may use constraints to determine when to advertise | The controller may use constraints to determine when to advertise | |||
| BGP-LS-SPF NLRI for BGP-LS peers. For example, a controller may | BGP-LS-SPF NLRI for BGP-LS peers. For example, a controller may | |||
| delay advertisement of a link between two peers the until the EoR | delay advertisement of a link between two peers the until the EoR | |||
| marker Section 5.3 has been received from both BGP peers and the BGP- | marker Section 5.3 has been received from both BGP peers and the BGP- | |||
| LS Link NLRI for the link(s) between the two nodes has been received | LS Link NLRI for the link(s) between the two nodes has been received | |||
| from both BGP peers. | from both BGP peers. | |||
| 5. BGP Shortest Path First (SPF) Routing Protocol Extensions | 5. BGP Shortest Path First (SPF) Routing Protocol Extensions | |||
| 5.1. BGP-LS SPF SAFI | 5.1. BGP-LS-SPF SAFI | |||
| This document introduces the BGP-LS-SPF SAFI with a value of 80. The | This document introduces the BGP-LS-SPF SAFI with a value of 80. The | |||
| SPF-based Decision Process (Section 6) applies only to the BGP-LS-SPF | SPF-based Decision Process (Section 6) applies only to the BGP-LS-SPF | |||
| SAFI and MUST NOT be used with other combinations of the BGP-LS AFI | SAFI and MUST NOT be used with other combinations of the BGP-LS AFI | |||
| (16388). In order for two BGP speakers to exchange BGP-LS-SPF NLRI, | (16388). In order for two BGP speakers to exchange BGP-LS-SPF NLRI, | |||
| they MUST exchange the Multiprotocol Extensions Capability [RFC4760] | they MUST exchange the Multiprotocol Extensions Capability [RFC4760] | |||
| to ensure that they are both capable of properly processing such an | to ensure that they are both capable of properly processing such an | |||
| NLRI. This is done with AFI 16388 / SAFI 80. The BGP-LS-SPF SAFI is | NLRI. This is done with AFI 16388 / SAFI 80. The BGP-LS-SPF SAFI is | |||
| used to advertise IPv4 and IPv6 prefix information in a format | used to advertise IPv4 and IPv6 prefix information in a format | |||
| facilitating an SPF-based Decision Process. | facilitating an SPF-based Decision Process. | |||
| skipping to change at line 1713 ¶ | skipping to change at line 1713 ¶ | |||
| "Advertisement of Multiple Paths in BGP", RFC 7911, | "Advertisement of Multiple Paths in BGP", RFC 7911, | |||
| DOI 10.17487/RFC7911, July 2016, | DOI 10.17487/RFC7911, July 2016, | |||
| <https://www.rfc-editor.org/info/rfc7911>. | <https://www.rfc-editor.org/info/rfc7911>. | |||
| [RFC7938] Lapukhov, P., Premji, A., and J. Mitchell, Ed., "Use of | [RFC7938] Lapukhov, P., Premji, A., and J. Mitchell, Ed., "Use of | |||
| BGP for Routing in Large-Scale Data Centers", RFC 7938, | BGP for Routing in Large-Scale Data Centers", RFC 7938, | |||
| DOI 10.17487/RFC7938, August 2016, | DOI 10.17487/RFC7938, August 2016, | |||
| <https://www.rfc-editor.org/info/rfc7938>. | <https://www.rfc-editor.org/info/rfc7938>. | |||
| [RFC9816] Patel, K., Lindem, A., Zandi, S., Dawra, G., and J. Dong, | [RFC9816] Patel, K., Lindem, A., Zandi, S., Dawra, G., and J. Dong, | |||
| "Usage and Applicability of BGP Link-State Shortest Path | "Usage and Applicability of BGP Link State (BGP-LS) | |||
| First (SPF) Routing in Data Centers", RFC 9816, | Shortest Path First (SPF) Routing in Data Centers", | |||
| DOI 10.17487/RFC9816, July 2025, | RFC 9816, DOI 10.17487/RFC9816, July 2025, | |||
| <https://www.rfc-editor.org/info/rfc9816>. | <https://www.rfc-editor.org/info/rfc9816>. | |||
| Acknowledgements | Acknowledgements | |||
| The authors would like to thank Sue Hares, Jorge Rabadan, Boris | The authors would like to thank Sue Hares, Jorge Rabadan, Boris | |||
| Hassanov, Dan Frost, Matt Anderson, Fred Baker, Lukas Krattiger, | Hassanov, Dan Frost, Matt Anderson, Fred Baker, Lukas Krattiger, | |||
| Yingzhen Qu, and Haibo Wang for their reviews and comments. Thanks | Yingzhen Qu, and Haibo Wang for their reviews and comments. Thanks | |||
| to Pushpasis Sarkar for discussions on preventing a BGP SPF router | to Pushpasis Sarkar for discussions on preventing a BGP SPF router | |||
| from being used for non-local traffic (i.e., transit traffic). | from being used for non-local traffic (i.e., transit traffic). | |||
| End of changes. 4 change blocks. | ||||
| 6 lines changed or deleted | 6 lines changed or added | |||
This html diff was produced by rfcdiff 1.48. | ||||