A Model for Mobile Point-to-Point Data-flow Networks without Channel Sharing

Abs t rac t . We present a fully abstract, denotationa] model for mobile, timed, nondeterministic data-flow networks whose components communicate in a point-to-point fashion. In this model components and networks of components are represented by sets of stream processing functions. Each stream processing function is required to be strongly guarded, generic and point-to, point. A stream processing function is strongly guarded if it is contractive with respect to the metric on streams. This property guarantees the existence of unique fix-points. Genericity is a privacy requirement specific to mobile systems. It guarantees that a function never accesses, depends on or sends a port whose name it does not already know. The point-to-point property guarantees that no port is known to more than two components: the sender and the receiver. Our model allows the description of a wide variety of networks in particular, the description of mobile, unbounded nondeterministic networks. We demonstrate some features of our model by specifying a communication central.