Constructing a Configurable Group RPC Service

Current Remote Procedure Call (RPC) services implement a variety of semantics, with many of the differences related to how communication and server failures are handled. The list increases even more when considering group RPC, a variant of RPC often used for fault-tolerance where an invocation is sent to a group of servers rather than one. This paper presents an approach to constructing group RPC in which a single configurable system is used to build different variants of the service. The approach is based on implementing each property as a separate software module called a micro-protocol, and then configuring the micro-protocols needed to implement the desired service together using a software framework based on the x-kernel. The properties of point-to-point and group RPC are identified and classified, and the general execution model described. An example consisting of detailed pseudocode for a modular implementation of a group RPC service is given to illustrate the approach. Dependency issues that restrict configurability are also addressed.