What are the characteristics of Segment Routing?

Segment Routing (SR) introduces a source routing model where the source node defines the path that packets take through the network by imposing a list of segments (instructions).

SR is aligned with SDN principles — the network is programmable and flexible.

SR does NOT depend on LDP or RSVP. Instead, SR uses extensions to IGP (OSPF or IS-IS) or BGP to distribute segment information.

SR simplifies the control plane by reducing the number of protocols needed for label distribution.

SR can work with or without a controller — the controller enhances path computation but is not mandatory for basic SR operation.