Ampol: Adaptive Messaging Policy Based System By

ii iii ABSTRACT Electronic messaging is a critical application that enables electronic communication between a very large collection of principals. However, it is challenged by limits in flexibility, integration, and security. Due to these limits principals are not typically willing to or in some cases not able to accept all types of communications from different parties. This thesis explores the idea of developing adaptive policy based messaging system AMPol, which aims to solve the limitation faced by messaging systems. AMPol approach is to enable parties to advertise communication policies to which a sender can adapt in order to get a message to a recipient on terms acceptable to the recipient. In this work different case studies are described to show how declarative requirements in the form of policy can help system achieve adaptability and flexibility. Especially a case study on email system explores the idea of using cutting edge web technology, web services, as a foundation for expressing and negotiating communications in a large scale system such as Internet email. In this work we have emphasized on the architectural aspects of the AMPol System and proposed architectural models for Policy Adaptation, Policy Negotiation and System Extension. In future we plan further investigations regarding theory, interoperability, experimentation, and security. Similarly, for wide scale adoption and to illustrate the effectiveness of our proposed approach we need to develop requirements for applications in different specific areas. In this work we have only presented applications in the area of internet email and VoIP communication to support our proposed theory. iv DEDICATIONS This thesis would not have been possible without the support of my parents, relatives and numerous friends. I am also especially thankful to my dear wife who endured this long process with me, always offering moral support and guidance. v ACKNOWLEDGMENTS