Other work in routing in AdHoc Networks explores a range of different aspects. As mobile devices and sensors will most likely be powered by battery, energy consumption is an important protocol characteristics. We are currently developing PIES, or Protocol-Independent Energy Savings, a general approach to reducing the energy consumption of routing protocols (as opposed to designing a specific energy-efficient routing protocol).
Another important characteristic of multihop wireless networks is the limited network capacity. These capacity limits are well-known and theoretical papers point out that per-node bandwidth tends towards 0 as the network scales in physical size and number of nodes. Even worse, current routing protocols tend to route data "through the middle" of the network, as they are looking for the shortest path. This will cause congestion in one part of the network, while transmission capabilities in other parts of the network (at "the edge") may be underutilized. We are currently investigating how to use the total available network capacity to its fullest by distributing the load in the network more evenly. There are some important trade-offs: as we route data over non-shortest paths, the number of packet retransmissions and the overhead to maintain these longer routes will increase, reducing the per-node throughput.