PODOS is a performance oriented distributed operating system being developed to harness the performance capabilities of a cluster computing environment. In order to address the growing demand for performance, we are designing a Distributed Operating System (DOS) that can utilize the computing potential of a number of systems. Earlier clustering approaches have traditionally stressed more on resource sharing or reliability and have given lesser priority to performance.PODOS adds just four new components to the existing Linux operating system to make it distributed. These components are a Communication Manager (CM), a Network Manager (NM), a Resource Manager (RM), and Global Interprocess Communication (GIPC). This paper addresses the communication mechanism in PODOS.In any distributed environment, communication appears to be the performance bottleneck. Thus, in PODOS, we have implemented a high-speed communication subsystem that short circuits the network protocol stack, and further performs packet multiplexing (Transmission-Groups) across multiple network interfaces thereby achieving a two-fold performance gain.In this paper we discuss the high-performance communication subsystem in PODOS and further analyze the performance gain achieved by comparing the variants of the PODOSprotocol with traditional networking protocol.