Security Threats and Jamming Attacks of Multi Channel Wireless Sensor Networks

Built upon a shared wireless medium, wireless sensor network is particularly vulnerable to jamming attacks. These attacks can easily be accomplished by an adversary by either bypassing MAC-layer protocols or emitting a radio signal targeted at jamming a particular channel. This paper considers a scenario where a sophisticated jammer jams an area in a multichannel wireless sensor network. The jammer controls the probability of jamming and transmission range to cause maximal damage to the network in terms of corrupted communication links. The jammer action ceases when it is detected by a monitoring node in the network, and a notification message is transferred out of the jamming region. The jammer is detected at a monitor node by employing an optimal detection test based on the percentage of incurred collisions. By considering multichannel networks some interesting issues arise. In that case defense strategy space has an additional dimension, that of channel switching. On the other hand jammer should find the optimal trade-off between jamming costs when jamming more channels and jamming reward in terms of higher chances to corrupt ongoing communication. The ability to recover from attacks and maintain an acceptable level of service degradation is a crucial aspect in the design of a wireless network. This paper also investigates the network restoration solutions in the event of jamming attacks via optimal channel re-assignment and by using honeypot techniques. KeywordsJamming, security, Jamming detection and mitigation, wireless sensor network.