Requirements for and Evaluation of RMI Protocols for Scientific Computing ∗ MadhusudhanGovindaraju, Aleksander Slominski, Venkatesh Choppella, Randall Bramley, Dennis Gannon Department of Computer Science Indiana University Bloomington, IN Abstract Distributed softwarecomponent architectures provide a promisingapproach tothe problem of building large scale, scientific Grid applications [18]. Communication in these component architectures is based on Remote Method Invocation (RMI)protocols that allow one softwarecomponent to invoke the functionality of another. Examples include Java remote method invocation (Java RMI)[25] and the new Simple Object Access Protocol (SOAP) [15]. SOAP has the advantage that many programming lan- guages and component frameworks can support it. This paper describes experiments showing that SOAP by itself is not efficient enough for large scale scientific applica- tions. However, when it is embedded in a multi-protocol RMI framework, SOAP can be effectively used as a universal control protocol, that can be swapped out by faster, more special purpose protocols when large data transfer speeds are needed. Key Words: Distributed computing, softwarecomponent systems, communication protocols,RMI, Java, SOAP. 1 Introduction Distributed component systems [1, 23, 26, 27] for scientific and engineering computing can potentially provide the same benefits that components do for business and financial com- puting: seamless access to remote resources, plug-and-play software composition without recompilation, access to specialized non-compute resources like data warehousing and vi- sualization, and improved software reuse. Component systems also can provide a natural milieu for large multidisciplinary research teams with pools of expertise distributed across the country. However, scientific computing presents challenges not typically found in com- mercial applications. In particular, the components encapsulate parallel programs sending large, complex, and rapidly changing data objects. * 0-7803-9802-5/2000/$10.00 c 2000 IEEE. 1 Proceedings of the IEEE/ACM SC2000 Conference (SC’00) 0-7803-9802-5/00 $17.00 © 2000 IEEE