Timed Migration and Interaction with Access Permissions

Ciobanu, G; Koutny, M

doi:10.1007/978-3-642-21437-0_23

Timed Migration and Interaction with Access Permissions

Lookup NU author(s): Professor Gabriel Ciobanu, Professor Maciej Koutny ORCiD

Downloads

Accepted version [.pdf]

Abstract

We introduce and study a process algebra able to model the systemscomposed of processes (agents) which may migrate within a distributed environmentcomprising a number of distinct locations. Two processes may communicate ifthey are present in the same location and, in addition, they have appropriateaccess permissions to communicate over a channel. Accesspermissions are dynamic, and processes can acquire new access permissions or losesome existing permissions while migrating from one location to another.Timing constraints coordinate and control the communication betweenprocesses and migration between locations. Thenwe completely characterise those situations when a processis always guaranteed to possess safe access permissions.The consequences of such a result are twofold. First, we are able to validatesystems where one does not need to check (at least partially)access permissions as they are guaranteednot to be violated, improving efficiency of implementation.Second, one can design systems in which processes are not blocked (deadlocked)because of the lack of dynamically changing access permissions.