G-SRv6

Generalized Segment Routing over IPv6 (G-SRv6) Networking Programming supports to encode multiple types of Segments in a SRH, called Generalized SRH (G-SRH). These Segments can be called Generalized Segment, and the ID can be Generalized Segment Identifier (G-SID), which may include an SRv6 SID(128 bits), C-SIDs, MPLS labels, or IPv4 tunnel information.

G-SRv6 can reduce the overhead of SRv6 by encoding the Compressed SIDs(C-SID) in SID list, and it also supports to program SRv6 SIDs and C-SIDs in a single SRH to support incremental deployment and smooth upgrade.

G-SRv6 is fully compatible with SRv6 with no modification of SRH, no new address consumption, no new route creation, and even no modification of control plane.

1. Compressed SRv6 SID List Requirements

Publication URL: https://datatracker.ietf.org/doc/html/draft-srcompdt-spring-compression-requirement

Introduction:

This document specifies requirements for solutions to compress SRv6 SID lists.

2. Compressed SRv6 SID List Analysis

Publication URL: https://datatracker.ietf.org/doc/html/draft-srcompdt-spring-compression-analysis

Introduction:

Several mechanisms have been proposed to compress the SRv6 SID list. This document analyzes each mechanism with regard to the requirements stated in the companion requirements document.

3. Generalized SRv6 Network Programming

Publication URL: https://tools.ietf.org/html/draft-cl-spring-generalized-srv6-np

Introduction:

As the deployment of SRv6, some new requirements are proposed, such as SRv6 compression, transporting over SR-MPLS/MPLS and IPv4 domains. Therefore, it is necessary to consider other types of segments or sub-paths in the end-to-end SRv6 network programming.

This document proposes Generalized Segment Routing over IPv6 (G-SRv6) Networking Programming, which supports to encode multiple types of Segments in a SRH, called Generalized SRH (G-SRH). These Segments can be called Generalized Segment, and the ID can be Generalized Segment Identifier (G-SID), which may include an SRv6 SID(128 bits), C-SIDs, MPLS labels, or IPv4 tunnel information.

This document also defines the mechanisms of Generalized SRv6 Networking Programming and the requirements of related protocol extensions of control plane and data plane.

4. Generalized Segment Routing Header

Publication URL: https://tools.ietf.org/html/draft-lc-6man-generalized-srh

Introduction:

Generalized SRv6 network programming defines the enhanced mechanisms of SRv6 to encode SRv6 SIDs, Compressed SIDs and even the MPLS labels or IPv4 tunnel information in a single SRH. This type of SRH is called Generalized SRH (G-SRH), which can reduce the overhead of SRv6 and also provide more flexibility for network programming. This document defines the encapsulation and packet processing of G-SRH.

5. Generalized SRv6 Network Programming for Compression

Publication URL: https://tools.ietf.org/html/draft-cl-spring-generalized-srv6-for-cmpr/

Introduction:

This document proposes Generalized Segment Routing over IPv6 (G-SRv6) Networking Programming for SRv6 compression.

G-SRv6 can reduce the overhead of SRv6 by encoding the Generalized SIDs(G-SID) in SID list, and it also supports to program SRv6 SIDs and G-SIDs in a single SRH to support incremental deployment and smooth upgrade.

G-SRv6 is fully compatible with SRv6 with no modification of SRH, no new address consumption, no new route creation, and even no modification of control plane. G-SRv6 for Compression is designed based on the Compressed SRv6 Segment List Encoding in SRH [I-D.filsfilscheng-spring-srv6-srh-comp-sl-enc] framework.

6. Compressed SRv6 Segment List Encoding in SRH

Publication URL: https://tools.ietf.org/html/draft-filsfilscheng-spring-srv6-srh-comp-sl-enc

Introduction:

This document defines a compressed SRv6 Segment List Encoding in the SRH. This solution does not require any SRH data plane change nor any SRv6 control plane change. This solution leverages the SRv6 Network Programming model.

7. Deployment Status

Publication URL: draft-cl-spring-generalized-srv6-for-cmpr: section-8.2

Introduction:

China Mobile had come up with China Unitechs, Huawei, ZTE and H3C to successfully deploy trial of G-SRv6 (with control plane) in their three province branch networks in November 2020, respectively.