Evaluation of Key Management Schemes in Wireless Sensor Networks

Wireless sensor networks are being deployed in wide variety of applications, including military sensing and tracking, environment monitoring, patient monitoring and tracking, smart environments, etc. When a wireless sensor network is deployed in such hostile environment, security becomes an extremely important issue. Confidentiality, integrity, and availability are typical security goals for wireless sensor networks. Providing these goals to secure communication among sensor nodes typically depends on the use of cryptographic schemes. When employing a cryptographic scheme, a key management service is always required. The objective of this paper is to evaluate the most important key management schemes in wireless sensor networks which are single network-wide key scheme, pairwise key establishment scheme, random key predistribution, and Q-composite random key predistribution scheme. The evaluation is performed in OMNET++ simulation environment and the metrics are selected as secure connectivity achievement, memory overhead, communication overhead, and resilience against node capture attacks. Based on the simulation results, the advantages and disadvantages of each scheme are presented. The simulation results show that there is no general purpose key management scheme that can fit all the security requirements of wireless sensor networks. However, in terms of the performance metrics, the most suitable scheme for wireless sensor networks is the random key predistribution scheme.