SYSTEMATIC COMPOSITION OF DISTRIBUTED OBJECTS - PROCESSES AND SESSIONS

We consider a system with the infrastructure for the creation and inte rconnection of large numbers of distributed persistent objects. This s ystem is exemplified by the Internet: potentially, every appliance and document on the Internet has both persistent state and the ability to interact with large numbers of other appliances and documents on the Internet. This paper elucidates the characteristics of such a system, and proposes the compositional requirements of its corresponding infra structure. We explore the problems of specifying, composing, reasoning about and implementing applications in such a system. A specific conc ern of our research is developing the infrastructure to support struct uring distributed applications by using sequential, choice and paralle l composition, in the anarchic environment where application compositi ons may be unforeseeable and interactions may be unknown prior to actu ally occurring, The structuring concepts discussed are relevant to a w ide range of distributed applications; our implementation is illustrat ed with collaborative Java processes interacting over the Internet, bu t the methodology provided can be applied independent of specific plat forms.