The state-oriented design of IP multicast may lead to the scalability problem, especially when there is a very large number of concurrent multicast groups in the network. Motivated by this problem, explicit multicast offers a stateless design using header space of multicast data packets. In this paper, we propose a novel stateless scheme called Linkcast that efficiently eliminates processing overhead of explicit multicast protocols. In Linkcast, the multicast sender encodes the tree listing its links in a proper way. The tree code is sent with every multicast data packet. Simulation results and experiments with real-trees show that Linkcast completely eliminates processing overhead of other explicit multicast protocols such as Xcast with comparable header size overhead.
