Cooperative detection for falsification and isolation of malicious nodes for wireless sensor networks in open environment

In wireless sensor networks, physical contact to sensor nodes by outsiders must be considered, because wireless sensor networks will be deployed in open environments that are populated by outsiders. Malicious outsiders can access a sensor node's storage and steal such security-related information as a key and inject malicious sensor nodes that can pass through authentication using that stolen key and perform falsifications in networks. The conventional schemes for falsification detection generally use a digital signature; however, these techniques require a completely secure key. Therefore, they cannot effectively work in situations when the key is not secure, and the reliability of the data is completely lost. Accordingly, in this paper, to protect the reliability of wireless sensor networks without a secure key, we propose a mechanism that detects malicious nodes by the cooperation of proper nodes and logically isolate the detected, malicious nodes from wireless sensor networks.