BGP LS PCEP

Project type: Main

You are all familiar with Border Gateway Protocol (BGP). BGP is known more as a networking application than a protocol  . For folks who are not familiar with BGP, it is a communication protocol between Internet routers, where connected networks are exchanged and how to reach each network is decided.

In the SDN world, as we have already learned, we move in a direction that helps us come out of the limitation of using legacy protocols. We don't want to use legacy protocols between the controller and switches within networks. We would like to use a method for direct programing of the fabric between the SDN controller and switches. However, in service provider networks, where they like to integrate a distributed MPLS or private IP VPN via SDN, there is very little chance to have large routers (such as Juniper T series or TX Matrix) with OpenFlow support.

BGP Path Computation Element Protocol (PCEP) is a southbound protocol used between the SDN controller and the routers in the network in order to override routing and forwarding tables (at a higher level).

ODL can use BGP PCEP as a southbound protocol to talk to routers. BGP PCEP is an extension of BGP that has support on specific routers.

BGP Linkstate (LS) is another BGP extension that allows BGP to distribute the link state information of routing protocols.

BGP PCEP has many use cases for service providers. It brings SP networks to a mid-generation state where the SDN controller will be able to influence the networks.