Should we break a wireless network into sub-networks?

In this paper we show that to achieve capacity of a wireless network, the global structure of the network should be considered. In other words, achieving capacity on the sub-networks of a wireless network does not guarantee achieving capacity globally. We illustrate this fact by some examples. Then we consider packet erasure wireless networks with limited sets of operations allowed at each node. We pose some interesting problems related to the optimal achievable rate of these networks and provide partial answers to some of them.