Enhanced BRPC Routing Procedure for PCE based Inter-domain Routing

摘要

IETF proposes Backward-Recursive PCE (Path Computation Element)-based Computation (BRPC) procedure to compute shortest constrained Traffic Engineering Label Switched Paths (TE LSPs) across domains with predetermined sequences. However, computing TE LSPs over predetermined domain paths imposes limitations on load-balancing of inter-domain networks. Hence, we enhance BRPC procedure with the ability to maintain and exchange the metrics of inter-domain path information. Therefore PCEs are able to compute BRPC domain paths dynamically. In our project, we implement a PCE based inter-domain routing OPNET model. The model simulates two scenarios including BRPC routing procedures across predetermined domain sequence and dynamically computed domain sequence. The connection blocking probabilities from different scenarios are measured as indicator of the TE improvement that the dynamic domain sequence brings.