Reliable multicast routing with uncertain sources

Multicast can jointly utilize the network resources when delivering the same content to a set of destinations; hence, it can effectively reduce the consumption of network resources more than individual unicast. The source of a multicast, however, does not need to be in a specific location as long as certain constraints are satisfied. This means the multicast can have uncertain sources, which could reduce the network bandwidth consumption more than a traditional multicast. Meanwhile, a reliable multicast becomes crucial in providing reliable services for many important applications. However, a prior minimal cost forest (MCF) for such a new multicast is not designed to support reliable transmissions. In this paper, we propose a novel reliable multicast routing with uncertain sources named ReMUS. To the best of our knowledge, we are the first to study the reliable multicast under uncertain sources. The goal is to minimize the sum of the transfer cost and the recovery cost, although finding such a ReMUS is very challenging. Thus, we design a source-based multicast method to solve this problem by exploiting the flexibility of uncertain sources when no recovery nodes exist in the network. Furthermore, we design a general multicast method to jointly exploit the benefits of uncertain sources and recovery nodes to minimize the total cost of ReMUS. We conduct extensive evaluations based on the real topology of Internet2. The results indicate that our methods can efficiently realize the reliable and bandwidth-efficient multicast with uncertain sources, irrespective of the settings of networks and multicasts.