Traffic engineering for proactive failure recovery of IP networks

As a promising approach to improve network reliability, proactive failure recovery (PFR) re-routes failure affected traffic to backup paths without waiting for the completion of IP routing convergence. However, the failure affected traffic may cause congestion if it is not carefully allocated over the backup paths according to their available capacity. A post failure traffic engineering (PostTE) scheme is proposed to balance the load in the PFR scheme. Loop-free backup paths are prepared in advance to cover all the potential single-link failures. The failure affected load is locally allocated to the backup paths through solving a linear programming (LP) problem. Most of the time, the maximum link utilization (MLU) of the network is minimized under both the failure and failure-free cases. For the tested education networks, the LP problem can be solved within milliseconds. © 2011 Tsinghua University Press.