Efficient message passing library support is clearly indispensable for the execution of WARPED [7]. The performance evaluation of several message passing libraries [8] clearly showed that MPICH performs better than other message passing libraries with respect to the following performance indices: send time, round trip time, probe time. The evaluation showed that TCP sockets perform better than MPICH with respect to the above mentioned factors. The evaluation used TCP sockets directly to measure the overhead with developing a message passing layer with TCP sockets. This lead to the design of a custom message passing library based on TCP/IP [5, 6] (TCPMPL) for WARPED applications. This section discusses the design of the custom message passing library over TCP/IP (TCPMPL). It begins with the motivation of the TCPMPL followed by the different design decisions made during the design phase of TCPMPL.