Electrical and Computer Engineering
Journal or Book Title
A sum-network is a directed acyclic network in which all terminal nodes demand the `sum' of the independent information observed at the source nodes. Many characteristics of the well-studied multiple-unicast network communication problem also hold for sum-networks due to a known reduction between instances of these two problems. Our main result is that unlike a multiple unicast network, the coding capacity of a sum-network is dependent on the message alphabet. We demonstrate this using a construction procedure and show that the choice of a message alphabet can reduce the coding capacity of a sum-network from 1 to close to 0.
Tripathy, Ardhendu and Ramamoorthy, Aditya, "Capacity of Sum-networks for Different Message Alphabets" (2015). Electrical and Computer Engineering Publications. 106.