This section describes the design of our prototype cluster. Given the complexity of the TCP multiple handoff mechanism, and the fact that simulation results indicate no substantial performance advantages of multiple handoff over back-end request forwarding, we decided to implement the back-end forwarding mechanism in the prototype.
Section 7.1 gives an overview of the various components of the cluster. Section 7.2 describes the TCP single handoff protocol. Section 7.3 describes tagging, a technique by which the front-end instructs the connection handling node to forward a given request to another back-end node. In Section 7.4, we describe how the back-end nodes fetch requests remotely from other nodes in a manner that keeps the server applications unchanged.