Effects of Denial of Sleep Attacks on Wireless Sensor Network MAC Protocols

As wireless platforms get less expensive and more powerful, the promise of wide-spread use for everything from health monitoring to military sensing continues to increase. Like other networks, sensor networks are vulnerable to malicious attack, however, the hardware simplicity of these devices makes defense mechanisms designed for traditional networks infeasible. This paper explores the denial-of-sleep attack, in which a sensor node's power supply is targeted. Attacks of this type can reduce sensor lifetime from years to days and have a devastating impact on a sensor network. This paper classifies sensor network denial-of-sleep attacks in terms of an attacker's knowledge of the MAC layer protocol and ability to bypass authentication and encryption protocols. Attacks from each classification are then modeled to show the impacts on three sensor network MAC protocols: S-MAC, T-MAC, and G-MAC. A framework for preventing denial-of-sleep attacks in sensor networks is also introduced. With full protocol knowledge and an ability to penetrate link-layer encryption, all wireless sensor network MAC protocols are susceptible to a full domination attack which reduces network lifetime to the minimum possible by maximizing the power consumption of the nodes' radio subsystem. Even without the ability to penetrate encryption, subtle attacks can be launched that reduce network lifetime by orders of magnitude. If sensor networks are to live up to current expectations, they must be robust in the face of network attacks, to include denial-of-sleep