Scaling MPLS across areas of an autonomous system using labeled interior border gateway protocol

摘要

Techniques are described for scaling Multiprotocol Label Switching (MPLS) across areas of an autonomous system using a labeled interior Border Gateway Protocol (iBGP). A method includes executing a first label distribution protocol at a border node at a border between two of a plurality of interior gateway protocol (IGP) areas of a single autonomous system (AS), and exchanging label distribution messages using the first label distribution protocol to establish a first intra-area label switched path (LSP) within a first one of IGP areas. The method also includes executing a labeled interior border gateway protocol at the border node, and exchanging label distribution messages using the labeled interior border gateway protocol to establish a hierarchical inter-area LSP that runs over the previously established first intra-area LSP, wherein the hierarchical inter-area LSP extends across the plurality of IGP areas of the AS.