Abstract
In this paper we investigate security problems which occur when exploiting a Linda-like data driven coordination model in an open environment. In this scenario, there is no guarantee that all the agents accessing the shared tuple space are trusted. Starting from a formalization of some typical security properties in the standard Linda coordination model, we present a novel data-driven coordination model which provides mechanisms to support the considered security properties. The first of these mechanisms supports logical partitions of the shared repository: in this way we can restrict the access to tuples stored inside a partition, simply by limiting the access to the partition itself. The second mechanism consists of adding to the tuples some extra information which permits to authenticate the producer of a tuple or to identify its reader/consumer. Finally, we support the possibility to define access control policies based on the kind of operations an agent performs on a tuple, thus discriminating between (destructive) input and (non-destructive) read permissions on each single tuple.