An Equivalence between Network Coding and Index Coding
  We show that the network coding and index coding problems are equivalent. This equivalence holds in the general setting which includes linear and non-linear codes. Specifically, we present an efficient reduction that maps a network coding instance to an index coding one while preserving feasibility. Previous connections were restricted to the linear case. 
Michelle Effros and Salim El Rouayheb and Michael Langberg
cs.IT cs.DM cs.NI math.IT