Web page: www.cs.virginia.edu/~jorg/research/hypercast/ One of the biggest challenges in computer networking is to meet the demand for advanced multicast services in support of large-scale multicast applications in wide-area networks. Numerous applications demand the availability of a scalable multicast service, including electronic software distribution, collaboration tools, multi-party video games, and distributed simulations. A major impediment for scalability of multicast applications is the need of multicast group members to exchange control information with each other. In this research project, a novel approach to the problem of scalable multicast is proposed where members of a multicast group are organized using a logical control structure with strong symmetrical properties, e.g., an n-dimensional hypercube. By exploiting the symmetry properties of the control structure, operations that require an exchange of feedback information between multicast group members can be efficiently implemented. The goal of the proposed project is to improve the scalability of multicast communications, and demonstrate that the feasibility to accommodate group sizes of several thousandmembers. Using analytical techniques, simulations, and measurement experiments, the fundamental limits and practical trade-offs of different approaches to structure large multicast groups will be investigated. A protocol prototype, called the HyperCast protocol, that maintains a logical hypercube in a packet switching network will be designed and implemented. If successful, the project will influence the currently ongoing research efforts on designing scalable multicast protocols. The solutions developed in this project will be applicable in many areas of computer science and engineering which require multicast communications, including parallel and distributed simulations, distributed information systems, global virtual databases, and meta-computing environments.
