Huawei Technologies RtBrick Inc Ciena Corporation Cisco Systems, Inc. China Telecom Segment Routing (SR) can be used to steer packets through an IPv6 or MPLS network using the source routing paradigm. SR enables any head- end node to select any path without relying on a hop-by-hop signaling technique (e.g., LDP or RSVP-TE). A Segment Routed Path can be derived from a variety of mechanisms, including an IGP Shortest Path Tree (SPT), explicit configuration, or a PCE. Since SR can be applied to both MPLS and IPv6 forwarding planes, a PCE should be able to compute SR-Path for both MPLS and IPv6 forwarding planes. The PCEP extension and mechanisms to support SR- MPLS have been defined. This document describes the extensions required for SR support for IPv6 data plane in the Path Computation Element communication Protocol (PCEP).