Explains how segment routing LSPs operate, how they differ from RSVP LSPs, and how segment lists guide traffic through networks.
SR LSPs use autoroute, forwarding adjacencies, and class-based forwarding, just like RSVP LSPs. Once the packet enters the tunnel, the different routing mechanisms determine the path. An RSVP LSP is first established along a path, with each node on the path accepting the reservation request and maintaining the reservation state. In contrast, SR LSPs rely on a segment list that is created at the LSP’s source node (head-end). This segment list, which is stored in the packet (demand), directs the traffic over a series of configured node segments and interface segments.
Cisco Crosswork Planning uses the terms SR LSPs that use segment lists, which contain segment list hops. In Cisco routing terminology, these terms are SR tunnels that use segment ID (SID) lists, which contain SIDs.