Comparison of network protocol and architecture for distributed virtual simulation environment

Abstract

In any distributed virtual simulation environment, the underlying network architecture and its protocols play an important part in its performance. This paper describes the different underlying protocols used in the support of the RTI implementation in the Federated Simulations Development Kit (FDK). The communication FM and MCAST modules were modified to support different protocols. The performance of two different protocols: TCP and a new Lightweight Reliable Multicast, called Pseudo Reliable Multicast Protocol (PRMP), running on top of two different network architectures Ethernet and Asynchronous Transfer Mode (ATM) were compared. The latter protocol was developed specifically to support the distributed virtual simulation environment. Furthermore, in the case of the ATM network architecture, the use of native ATM-API was also implemented and its performance compared with the other protocols. The benchmarks used to compare their performance are Latency and Time Advance Request Benchmark. The results show that PRMP outperforms the other protocol techniques when the number of subscribers are large and when the bandwidth is limited. But it has some additional latency overhead, due to additional processing required to provide the reliability needed by the sender and receivers. Comparing the network architecture, the benchmark performance of the above protocols operating on top of 100BaseT switch network performs much better than over ATM network, although the transmission speed is much higher in the case of the latter.