A theory of processes with localities, with I. Castellani, M. Hennessy and A. Kiehn, in Formal Aspects of Computing (FAC), Vol 6 (1994), 165-200.

Abstract: (see also RR-1632)
We study a notion of observation for concurrent processes which allows the observer to see the distributed nature of processes, giving explicit names for the location of actions. A general notion of bisimulation related to this observation of distributed systems is introduced. Our main result is that these bisimulation relations, particularized to a process algebra extending CCS, are completely axiomatizable. We discuss in details two instances of location bisimulations, namely the location equivalence and the location preorder.