Abstract

Software technology is undergoing a transition from monolithic systems, constructed according to a single overall design, into conglomerates of semi-autonomous, heterogeneous and independently designed subsystems, constructed and managed by different organizations, with little, if any, knowledge of each other. Among the problems inherent in such conglomerates none is more serious than the diffculty to control the activities of the disparate agents operating in it, and the diffculty for open groups of such agents to coordinate their activities with each other. We argue that the nature of coordination and control required for such systems calls for the following principles to be satisfied: (1) coordination policies need to be enforced; (2) the enforcement needs to be decentralized; and (3) coordination policies need to be formulated explicitly -- rather than being implicit in the code of the agents involved -- and they should be enforced by means of a generic, braod spectrum mechanism; and (4) it should be possible to deploy and enforce a policy incrementally, without exacting any cost from agents and activities not subject to it. We describe a mechanism called law-goverened interaction (LGI), currently implemented by the Moses toolkil, which has been designed to satisfy these principles. We show that LGI is at least as general as a conventional centralized coordination mechanism (CCM), and that it is more scalable, and generally more efficient than CCM.

Citations