Coordination with Multicapabilities

In the context of open distributed systems, the ability to coordinate agents coupled with the possibility to control the actions they perform is important. As open systems need to be scalable, capabilities may provide the best-fit solution to overcome the problems caused by the loosely controlled coordination of tuple-space systems. Acting as a ‘ticket’, capabilities can be given to the chosen agents, granting them different privileges over different kinds of data—thus providing the system with a finer control on objects’ visibility to agents. One drawback of capabilities is that they can only refer to named objects—something that is not universally applicable since, unlike tuple-spaces, tuples are nameless. This paper demonstrates how the advantages of capabilities can be extended to tuples, with the introduction of multicapabilities, which generalise capabilities to collections of objects. We also present discussions on implementation and application examples to illustrate the use of capabilities and multicapabilities in tuple-space systems.