Overcast: Reliable Multicasting with an Overlay Network
Abstract
Overcast is an application-level multicasting system that can be incrementally deployed using today's Internet infrastructure. These properties stem from Overcast's implementation as an overlay network. An overlay network consists of a collection of nodes placed at strategic locations in an existing network fabric. These nodes implement a network abstraction on top of the network provided by the underlying substrate network.
Overcast provides scalable and reliable single-source multicast using a simple protocol for building efficient data distribution trees that adapt to changing network conditions. To support fast joins, Overcast implements a new protocol for efficiently tracking the global status of a changing distribution tree.