Detection of Selective Forwarding Attacks in Heterogeneous Sensor Networks

Security is crucial for wireless sensor networks deployed in the military and other hostile environments. Due to the limited transmission range, a sensor node may need multiple hops of transmissions to deliver a packet to the base station. An attacker can launch the selective forwarding attack and drop a portion of packets for which it needs to relay while forward the rest. Selective forwarding attack is hard to detect, since packet drops in sensor networks may be caused by unreliable wireless communications or node failures. In this paper, first we describe an efficient scheme for reporting packet drops, then we present an effective scheme for detecting the selective forwarding attack in a heterogeneous sensor network. The scheme utilizes powerful high-end sensors and is based on the sequential probability ratio test. Our extensive simulations show that the proposed scheme achieves high detection ratio and very low false alarm rate.