SEGMENT ROUTING FOR INTERNET PROTOCOL VERSION 6 DATAPLANE BASED PROTECTED PATH TRAFFIC FLOW SIGNALING
Publication Date: 2017-Aug-31
The IP.com Prior Art Database
Described are techniques to reduce Total Time on Backup (TTOB) for Segment Routing for Internet Protocol version 6 (SRv6). A transit node may redirect a packet over a backup path (built using any Loop-Free Alternate (LFA) technique). The transit node may encapsulate the packet in an outer Segment Routing Header (SRH) and set the P flag in the outer SRH. A Segment Routing (SR) node may perform a lookup in the SRH and determine that the path to the next segment is the backup path. If the SR node makes this determination, the SR node may set the P flag in the SRH. If a packet is received with the P flag set in outer SRH to signal that the node is decapsulating the header, the node may propagate the P flag from the outer to the inner SRH. When applied by multiple nodes, this may help propagate the flag from any Point of Local Repair (PLR) to egress. The egress may use the flag to signal back to ingress. For example, if a Bidirectional Forwarding Detection (BFD) packet is received with the P flag set, the egress may signal back with a new code. If a data packet is received with the P flag and the inband BFD set, the egress may signal with a new code.