The term wireless sensor network is applied broadly to a range of significantly different networking environments. On the other hand there exists a substantial body of research on key establishment in wireless sensor networks, much of which does not pay heed to the variety of different application requirements. We set out a simple framework for classifying wireless sensor networks in terms of those properties that directly influence key distribution requirements. We fit a number of existing schemes within this framework and use this process to identify areas which require further attention from key management architects.
