Con dentiality In Sensor Networks : Transactional Information

In a sensor network environment, elements such as message rate, message size, mote frequency, and message routing can reveal information about the sensors deployed, frequency of events monitored, network topology, parties deploying the network, and location of subjects and objects moving through the networked space. Collectively, we refer to these elements as transactional data. Where the con dentiality of the content of the networks communications has been secured through encryption and authentication techniques, the ability of network outsiders and insiders to observe elements or the totality of this transactional data can also compromise network con dentiality. This paper describes four types of transactional data typically observable in sensor networks and discusses the information that can be derived through its observation and analysis. The paper argues that measures to limit the availability and utility of transactional data are essential to preserving con dentiality in sensor networks.