Enhance internet routing availability with multipath inter-domain routing

As the fundamental of Internet architecture, inter-domain routing and its availability are the concern of the community. The de facto inter-domain routing protocol, BGP, selects and announces only single route for each destination prefix. That will lead to when router or link failure occurs, network experience unavailability, even if feasible path exists. To address this issue, some proposals speed up the routing protocol convergence to reduce the transient loss of reachability during route convergence. In this paper, we present the multipath inter-domain routing by revising the current BGP protocol. The basic ideas is to add the MULTIPATH capability option to BGP protocol for supporting the negotiation between BGP peers, and modify the routing decision process for permitting route announce candidate routes to its neighbor routers. Our proposal provides the backwards compatible with the traditional BGP systems. The benefits of the scheme are demonstrated using the realistic simulations.