On the Effect of Imperfect Range Estimates on Base Station Anonymity in Wireless Sensor Networks

In recent years, Wireless Sensor Networks (WSNs) have become valuable assets to both the commercial and military communities with applications ranging from industrial control on a factory floor to reconnaissance of a hostile border. A typical WSN topology that applies to most applications allows sensors to act as data sources that forward their measurements to a central sink or base station (BS). The unique role of the BS makes it a natural target for an adversary that desires to achieve the most impactful attack possible against a WSN. An adversary may employ traffic analysis techniques such as evidence theory to identify the BS based on network traffic flow even when the WSN implements conventional security mechanisms. This motivates a need for WSN operators to achieve improved BS anonymity to protect the identity, role, and location of the BS. Location anonymity assessments depend on an adversary´s ability to achieve accurate range estimates to map intercepted traffic to the target network´s topology. These range estimates may suffer from a variety of errors depending on the specific RF propagation environment in which the target system operates. BS anonymity estimates in turn may be degraded depending on the severity of the ranging errors. In this paper we examine the effect of Gaussian distributed ranging errors on BS anonymity using evidence theory analysis and simulation.