Providing protection and restoration with distributed multipath routing

Multipath routing is an interesting tool to provide a fast reaction time to protect networks from failure or congestion. Indeed, a local alternate path computation allows to faster reroute the traffic without flooding the entire network with Link State Advertisements. The restoration depends therefore on the protection guaranteed by each router. Distributed techniques allow to entrust the potential restoration to each router where it is possible. We distinguish multipath routing and fast rerouting techniques to underline the possibility to use alternate routes for load balancing or just as backup solution. In this paper we first summarize our incoming interface multipath routing technique and then analyze its capabilities in terms of protection. We evaluate several routing techniques to achieve a good coverage. Results indicate that our hop by hop routing multipath protocol performs almost as well as the best unipath rerouting technique whereas it can also be used for proportional routing.