Minimum Interference Routing with Applications to MPLS Traffic Engineering

This paper presents a new algorithm for dynamic routing of bandwidth guaranteed tunnels where tunnel routing requests arrive one-by-one and there is no a priori knowledge regarding future requests. This problem is motivated by service provider needs for fast deployment of bandwidth guaranteed services and the consequent need in backbone networks for fast provisioning of bandwidth guaranteed paths. Offline routing algorithms cannot be used since they require a priori knowledge of all tunnel requests that are to be routed. Instead, on-line algorithms that handle requests arriving on-by-one and that satisfy as many potential future demands as possible are needed. The newly developed algorithm is an on-lin algorithm and is based on the idea that a newly routed tunnel must follow a route that does not "interfere to much" with a route that may be critical to satisfy a future demand. We show that this problem is NP-hard. We then develop a path selection heuristic that is based on the idea of deferred loading of certain "critical" links.