CHI-NOG 2016: Segment Routing – Traffic Engineering


In this talk, we would look at Segment Routing traffic engineering primarily focused around inter-area/multi-domain traffic engineering. We will look at how certain approaches with Segment Routing can help in solving the challenges associated with multi-domain traffic engineering in a simple and scalable manner.

We will look into various components associated with multi-domain traffic engineering and approaches to solve multi-domain traffic engineering.

  • PCE
  • PCEP
  • On Demand Next-Hop
  • BGP SRTE Dynamics
  • PCE HA

Segment Routing (SR) works by encoding a path across a network as an ordered list of segments, which may be links, multi-hop tunnels between nodes, and more. SR uses today’s dataplane technologies without any modification, supports MPLS, IPv4 and IPv6, and requires only very modest changes to existing routing protocols. SR is also fully documented in IETF drafts with both multi-vendor and multi-operator contribution, thereby increasing the likelihood of interoperable implementations. Segment Routing allows operators to program new service topologies without the traditional concerns around network state explosion. Using SDN procedures, the head end can program a ordered list of segment identifiers (MPLS labels, IPv6 routing headers) that enable explicit source routing. This can allow for service level differentiation, potentially providing new enhanced service offering opportunities for operators. SR can be introduced slowly into a network without any flag day events, thereby minimizing disruption.