Abstract
Unattended wireless sensor networks (UWSNs) are operated in hostile environments without constant supervision by a trusted sink; so it faces the risk of compromising by adversaries (ADVs). In this study, proposed is a cooperative hybrid self-healing randomised distributed (CHSHRD) scheme, a new mechanism to enhance the confidentiality of the data collected by UWSNs. The proposed scheme employs both proactive and reactive peers to ensure both backward secrecy and data reliability. It helps the unattended sensors to self-heal and restore their backward secrecy by asking for help from the best qualified neighbours to generate a new secret key to regain their secrecy. The sick sensors also use the best qualified neighbours to distribute the data parts among them to protect the data from eavesdropping and this will enhance the data reliability. In this study, they also present a powerful, realistic and agile ADV model and show how CHSHRD scheme can result in sensor regaining secrecy and achieving high data reliability, despite the adversary efforts to the contrary. The evaluation of the proposed scheme relies on both theoretical probabilistic results and simulation results that compare the proposed scheme to other protection schemes. The results show that this hybrid scheme provides better protection than other schemes that use either proactive or reactive peers.