Linguistic support of receptionists for shared resources

This paper addresses linguistic issues that arise in providing support for shared resources in large scale concurrent systems. Our work is based on the Actor Model of computation which unifies the lambda calculus, the sequential stored-program and the object-oriented models of computation. We show how receptionists can be used to regulate the use of shared resources by scheduling their access and providing protection against unauthorized or accidental access. A shared financial account is an example of the kind of resource that needs a receptionist. Issues involved in the implementation of scheduling policies for shared resources are also addressed. The modularity problems involved in implementing servers which multiplex the use of physical devices illustrate how delegation aids in the implementation of parallel problem solving systems for communities of actors.