A middleware architecture to facilitate distributed programming: DAROC: Data-Activated Replicated Object Communications

Programming distributed computer systems is difficult because of complexities in addressing remote entities, message handling, and program coupling. As systems grow, scalability becomes critical, as bottlenecks can serialize portions of the system. When these distributed system aspects are exposed to programmers, code size and complexity grow, as does the fragility of the system. This paper describes a distributed software architecture and middleware implementation that combines object-based blackboard-style communications with data-driven and periodic application scheduling to greatly simplify distributed programming while achieving scalable performance. Data-Activated Replication Object Communications (DAROC) allows programmers to treat shared objects as local variables while providing implicit communications.