Architectural description based Overlay Networks

Overlay Networks are heavily used in Distributed computing applications. They often have heterogeneous architectures, such as Client Server, Peer to Peer or Hybrid. In this work, we try to abstract the Architecture of an Overlay Network into a document called an Architectural Description (AD). The Architectural Description document may contain the Roles and the Relationships of a particular Overlay Architecture. The Architectural Description documents may be exchanged among the nodes and parsed by the nodes themselves, enabling the nodes to adopt different roles and relationships. By introducing a new AD, a new Overlay Network can be formed dynamically. AD based Overlay Networks may open many new possibilities in Overlay Networking. This approach would allow heterogeneous Overlays to work collaboratively, while maintaining their respective Security settings using ´Security Roles´. It would also allow multiple overlays to be dynamically ´super-imposed´ on top of each other. Apart from that, the AD based approach would allow the same set of nodes to switch between heterogeneous overlays at different time intervals. Architectural Descriptions can also be used as an efficient means of Security key management. A prototype framework was developed to explore these features, using sample distributed file sharing applications. Moreover, the possible enhancements and future directions of AD based approach in developing Overlay Networks are also discussed.