BGP Segment Routing(SR) Extension

This feature adds support for BGP Segment Routing-Traffic Engineering (SR-TE) policy subsequent address family identifier (SAFI) as described in draft-ietf-idr-segment-routing-te-policy. However, only BGP receive support is added through this feature. BGP send support is not implemented through this feature.

The SR-TE policies network layer reachability information (NLRI) consists of a three-value tuple: . The Distinguisher is used to differentiate the originators of the same SR-TE policy, encoded as . The BGP UPDATE message containing SR-TE policies NLRI includes the Tunnel Encapsulation attribute as well, which can include various information, such as the label stack to be used to program a label-switched path (LSP) or the binding SID used to map the traffic to the SR-TE LSP.

This feature also adds support for the following functions:

• Support a mapping between a binding SID label and an outgoing SR-TE path
• Support a mapping between a binding SID label and multiple outgoing SR-TE paths (with weighted or non-weighted ECMP)
• The SR-TE policy steering mechanisms, including the steering mechanism based on color extended community ?CO? flags of 00 or 11