BGP Labeled Unicast
As well as distributing routes, BGP with Multiprotocol Extensions (MP-BGP) can advertise MPLS label mappings that are mapped to routes. BGP Labeled Unicast (BGP-LU) attaches an MPLS label to an advertised IGP prefix and distributes the MPLS label mapped to the prefix to its peers.
With BGP-LU, a network can be divided into multiple regions to limit the total number of LSPs and enable failures to be contained and restored in a single region These regions operate separate instances of the IGP and use BGP-LU to advertise route information between inter-region routers.
A configuration for BGP-LU uses these type of nodes:
• Provider Edge (PE) nodes advertise label bindings to remote PEs in other regions. These advertisements only affect the PE routers and the ABRs and not provider routers (“P”) in the core network.
• Area Border Router (ABR) nodes advertise the label bindings to remote PEs in other regions.
Last modified date: 07-13-2023