ABSTRACT
The focus of this paper is on specifying a coordination model for building secure distributed collaboration and workflow systems from their high level specifications. We identify here unique requirements of security and coordination in dynamic collaboration environments. We present a role-based model for specifying these requirements. This specification model supports hierarchical structuring of a large collaboration environment using nested activities, which can be created dynamically. We briefly describe how a middleware is used to realize and support a collaboration environment from its specifications, enforcing the required policies for coordination and security.
