Improvements on fault localization in GMPLS-based networks

With the increasingly urgent need for robust and reliable networks, the issue of protection and restoration in GMPLS-based networks becomes very important. In order to perform protection and restoration fast and effectively, a simple and efficient fault localization scheme, which is the necessary first step to trigger protection and restoration procedures, must be provided. Considerable efforts have been made to improve fault localization procedure for GMPLS-based networks. However, some serious flaws still remain in the protocol released by IETF recently. In the paper, two serious flaws lying behind the current fault localization scheme, which was defined in the latest standard of GMPLS, are pointed out and corresponding solutions are proposed. By employing a bi-directional data/TE link failure notification approach, during the fault localization procedure, unnecessary signaling overhead and redundant fault correlation procedures are avoided. The theoretical analyses and performance comparisons show that, by using our proposed scheme, the data link failure is located with much lower signaling overhead and network resource occupancy.