Abstract
In this paper we analyze the requirements access control mechanisms must fulfill in the context of group communication and define a framework for supporting fine-grained access control in client-server group communication systems. Our framework combines rolebased access control mechanisms with environment parameters
(time, IP address, etc.) to provide support for a wide range of applications with very different
requirements. While the access control policy is defined by the application, its efficient enforcement is
performed by the group communication system.
