Multiparty Negotiation of Dynamic Distributed Object Services

Abstract Object-oriented programming (OOP) has proven a very useful paradigm for supporting client-server computing within the context of local-area networks, where stable assumptions can be made about the available resources and services and where interactions between clients and servers are relatively simple. By implementing servers as objects, access to services can be kept separate from implementation, thus making client-server applications both more flexible and easier to maintain. Now that we are moving from single enterprise computing to the inter-organizational information world of the Internet and WWW, object-oriented programming must adapt itself to new client-server requirements. Specifically, there is need of coping with situations where new services can be dynamically added to servers, and where clients may need to coordinate the access to multiple services, rather than to single individual ones. In this paper, we describe the object model of the Coordination Language Facility, a programming framework that extends OOP with constructs that support dynamic services and multi-service coordination. We illustrate the use of these constructs through the application domain of distributed workflow.