A Note on the Multiple Unicast Capacity of Directed Acyclic Networks
Network coding has emerged as an interesting alternative to routing in the next generation of networks. In particular, it is well-known that the network coding is a provably capacity achieving strategy for network multicast. The work of provides a nice algebraic framework for reasoning about network coding, and significantly simplifies the proofs of, and suggests network code design schemes. However, general network connections, such as multiple unicasts are more difficult to understand under network coding. In a multiple unicast connection, there are several source terminal pairs; each source wishes to communicate to its corresponding terminal.