As computers become pervasive in the home and community, a variety of new applications will emerge which will allow widely distributed users to share and manipulate continuously evolving
information. The problem of providing secure access to such information in a timely fashion is highly challenging in wide area environments where the applications will be deployed. The project focuses on an integrated approach that will explore the scalability and security of such demanding applications. To provide interactive response time to requests for shared information, a variety of consistency models and protocols will be developed, and they will specially address the timeliness needs of applications. To secure the applications, a new context-aware security approach will be explored. In this approach, access can be controlled not only based on the user that makes the request but also on the security relevant context of the request. An access control model based on this approach as well as relevant security services will be developed. A general service architecture that employs the scalability mechanisms and the associated services will be built in a distributed object based middleware system. The effectiveness of these services will be evaluated using novel applications and workloads.