Treemap - The Fast Routing Convergence Method for Application Layer Multicast

Application layer multicast (ALM) is an alternative to overcome many problems that prevent IP multicast from widely using. However, when the overlay route changes, it takes time for end-hosts to update new routing table. In this paper, we propose Treemap a technique to alleviate this problem. The main contribution of Treemap is to perform application layer routing which is self contained in a packet. As a result, end-hosts do not need to update new overlay route, yielding fast route adaptation when the overlay route changes. Furthermore, the Treemap technique can be used to extend Xcast6 (Explicit Multi-unicast for IPv6). Xcast6 Treemap sends data in network layer multicast with the support of Xcast router, otherwise it works like ALM. With nominal packet header processing, Xcast6 Treemap is well suited for loss/time sensitive applications such as video conference.