G. Pujolle Laboratoire MASI Universite P. et M. Curie 45 avenue des Etats-Unis 78000 Versailles France In this paper, we present a general approach to obtain the exact stability condition of systems with resource sharing. Two kinds of allocation disciplines are studied: 1.the allocation may be performed in parallel: as soon as a resource is free , if a customer is waiting, the allocation begins...