Half-pipe anchoring: an efficient technique for multiple connection handoff

We present half-pipe anchoring, a technique that enables multiple connection handoff mechanisms that are efficient and easy to implement. In a server cluster, these mechanisms result in better resource utilization and improved scalability. More importantly, half-pipe anchoring supports the only connection handoff mechanism that operates efficiently in heterogeneous clusters composed of specialized nodes. The key idea behind our approach is to decouple the two unidirectional half-pipes that make up a TCP connection between a client and a cluster. We anchor the unidirectional half-pipe from the client to the cluster at a designated server while allowing the half-pipe from the cluster to the client to migrate on a per-request basis to an optimal server where the request is best serviced We describe the design and implementation of a multiple connection handoff mechanism in the Linux kernel that demonstrates the benefits of our technique.