MAC Security and Security Overhead Analysis in the IEEE 802.15.4 Wireless Sensor Networks

Sensor networks have many applications. However, with limited resources such as computation capability and memory, they are vulnerable to many kinds of attacks. The IEEE 802.15.4 specification defines medium access control (MAC) layer and physical layer for wireless sensor networks. In this paper, we propose a security overhead analysis for the MAC layer in the IEEE 802.15.4 wireless sensor networks. Furthermore, we survey security mechanisms defined in the specification including security objectives, security suites, security modes, encryption, authentication, and so forth. Then, security vulnerabilities and attacks are identified. Some security enhancements are proposed to improve security and to prevent these attacks such as same-nonce attack, denial-of-service attack, reply-protection attack, ACK attack, and so forth. Our results show that, for example, with 128-bit key length and 100 MIPS, encryption overhead is 10.28 s per block, and with 100 MIPS and 1500-byte payload, the encryption overhead is as high as 5782.5 s.