Global Path Service: A new inter-domain routing scheme

This paper introduces a new inter-domain routing scheme based on a centralized routing service: Global Path Service (GPS). This routing service provides alternate inter-AS paths different to ordinary BGP routes. This scheme facilitates diversified inter-AS forwarding paths through GPS-enabled ASes offering their inter-domain transit tunnels (e.g. MPLS). A GPS center concatenates those transit tunnels into available GPS paths. This routing scheme facilitates a kind of diversified source routing at the AS-level. When a packet needs to be forwarded, the local router queries the GPS routing service to obtain a Path ID which will serve as a kind of source routing primitive. The packet will be routed based on this path ID from AS to AS, using tunnels to cross intermediate ASes on the given path. This paper illustrates a framework to implement the infrastructure of diversified routing. This infrastructure should allow for novel inter-domain routing services, such as inter-domain Quality of Service (QoS) or multipath routing. We evaluate the availability, scalability and path diversity of the GPS service by simulations.