  This paper investigates the interplay between cooperation and achievable
rates in multi-terminal networks. Cooperation refers to the process of nodes
working together to relay data toward the destination. There is an inherent
tradeoff between achievable information transmission rates and the level of
cooperation, which is determined by how many nodes are involved and how the
nodes encode/decode the data. We illustrate this trade-off by studying
information-theoretic decode-forward based coding strategies for data
transmission in multi-terminal networks. Decode-forward strategies are usually
discussed in the context of omniscient coding, in which all nodes in the
network fully cooperate with each other, both in encoding and decoding. In this
paper, we investigate myopic coding, in which each node cooperates with only a
few neighboring nodes. We show that achievable rates of myopic decode-forward
can be as large as that of omniscient decode-forward in the low SNR regime. We
also show that when each node has only a few cooperating neighbors, adding one
node into the cooperation increases the transmission rate significantly.
Furthermore, we show that myopic decode-forward can achieve non-zero rates as
the network size grows without bound.
