摘要：Coordination is essential for dynamic distributed systems whose componentsexhibit interactive and autonomous behaviors. Spatially distributed, locallyinteracting, propagating computational fields are particularly appealing forallowing components to join and leave with little or no overhead. Computationalfields are a key ingredient of aggregate programming, a promising softwareengineering methodology particularly relevant for the Internet of Things. Inour approach, space topology is represented by a fixed graph-shaped field,namely a network with attributes on both nodes and arcs, where arcs representinteraction capabilities between nodes. We propose a SMuC calculus wheremu-calculus- like modal formulas represent how the values stored in neighbornodes should be combined to update the present node. Fixpoint operations can beunderstood globally as recursive definitions, or locally as asynchronousconverging propagation processes. We present a distributed implementation ofour calculus. The translation is first done mapping SMuC programs into normalform, purely iterative programs and then into distributed programs. Some keyresults are presented that show convergence of fixpoint computations under fairasynchrony and under reinitialization of nodes. The first result allows nodesto proceed at different speeds, while the second one provides robustnessagainst certain kinds of failure. We illustrate our approach with a case studybased on a disaster recovery scenario, implemented in a prototype simulatorthat we use to evaluate the performance of a recovery strategy.
关键词：F.1.2;D.1.3;C.2.4;Computer Science - Logic in Computer Science
