Base station anonymity distributed self-assessment 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. In most applications, the sensors act as data sources and forward information generated by event triggers 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 with the least amount of effort. Even if a WSN employs conventional security mechanisms such as encryption and authentication, an adversary may apply traffic analysis techniques to identify the BS. This motivates a significant need for improved BS anonymity to protect the identity, role, and location of the BS. Previous work has proposed anonymity-boosting techniques to improve the BS´s anonymity posture, but all require some amount of overhead such as increased energy consumption, increased latency, or decreased throughput. If the BS understood its own anonymity posture, then it could evaluate whether the benefits of employing an anti-traffic analysis technique are worth the associated overhead. In this paper we propose two distributed approaches to allow a BS to assess its own anonymity and correspondingly employ anonymity-boosting techniques only when needed. Our approaches allow a WSN to increase its anonymity on demand, based on real-time measurements, and therefore conserve resources. The simulation results confirm the effectiveness of our approaches.