Integrated dynamic routing of LSPs in IP over WDM networks: Full protection and partial spatial-protection

We investigate the problem of Label Switched Path (LSP) protection using online integrated routing in IP over WDM networks. While certain mission- and time-critical applications require guaranteed 100% protection, other applications may have less stringent protection requirements. We consider these two kinds of protection scenarios and refer them as full protection (FP) and partial protection (PP), respectively. We first consider the full protection scenario and develop two integrated routing algorithms to select primary LSPs and backup LSPs, respectively. Next we consider the partial protection scenario, particularly, the partial spatial-protection (PSP) wherein the working traffic is unprotected against the failure of certain links along the primary LSPs according to the specified connection protection requirements. We develop an algorithm to determine the set of unprotected links with the objective of improving the backup resource sharing efficiency. We evaluate the performance of the proposed algorithms on the NSFNET and Pan-European optical networks.