Abstract-Recent research has considered various architectural approaches in which route determination occurs separately from forwarding. Such offers many advantages, but also brings a number of challenges, not least of which is scalability. In this paper we consider the problem of computing domain-level end-toend routes in the Internet. We describe a system architecture and a prototype route computation service that provides performance information along with paths. The results of our experiments, which involve updating billions of routes and serving thousands of requests per second, suggest that the resource requirements for a single-domain end-to-end path service (i.e., a service that provides paths from one access domain to all others) are fairly modest