Martin, Rüdiger; Menth, Michael; Spoerlein, Ulrich (Institute of Computer Science, University of Würzburg, Am Hubland, D-97074Würzburg, Germany)
Link and router failures lead to disconnection in networks, which can possibly be repaired by restoration and protection switching mechanisms within seconds or milliseconds. However, redirected traffic causes congestion unless sufficient backup capacity is provided for failure scenarios. In previous work we showed that the required backup capacity for the protection switching mechanism “self-protecting multipath” (SPM) can effectively be reduced by optimized load balancing when resilience against single failures is needed. In this work, we look at double-failure resilience, compare the backup capacity demands for different levels of multi-failure survivability both for the optimized SPM and shortest path routing (SPR), and study the impact of unprotected multi-failures in such networks.