Ambassadors: structured object mobility in worldwide distributed systems

In many distributed systems applications deployed on the worldwide scale, it is latency, rather than bandwidth, that is the primacy determinant of performance. This paper describes Ambassadors, a communication technique using mobile Java objects within an RPC/RMI-like communication structure. Ambassadors minimise the aggregate latency of sequences of inter-dependent remote operations by migration of code to the vicinity of the server to execute those operations. Furthermore, because Ambassadors migrate within an RPC/RMI-like structure communication has well defined failure semantics, an important characteristic in supporting effective software engineering of distributed systems.