Secure topology maintenance and events collection in WSNs

Topology Maintenance Protocols (TMPs) are key for operating Wireless Sensor Networks (WSNs). Their adoption serves a few goals, such as, to save energy, to avoid collisions in communications and to have an adequate number of nodes monitoring the environment-by alternating duty cycles with sleep cycles on the sensor nodes. While effectiveness of TMPs protocols is widely addressed, security is an overlooked feature. Indeed, while different TMPs have been presented in the literature, few of them address the security issues. In particular, only recently a secure TMP protocol that does not require pair-wise node confidentiality has been proposed: Sec-TMP. The aim of Sec-TMP is to enforce event delivery to the Base Station while providing a standard topology maintenance service to the WSN. In this paper, we provide a thorough assessment of our previous preliminary proposal of Sec-TMP, with particular reference to its effectiveness and security. First, we investigate the energy consumption introduced by TMPs protocols. Second, we show that Sec-TMP performs well without any assumption neither on the show-up time of data-collecting node, nor on their mobility model. In particular, we test Sec-TMP against a realistic unpredictable data-collecting mobility scenario, that also brings in new security issues. A thorough security analysis of the proposed solutions to these new issues is also provided. Finally, extensive simulations support the quality of Sec-TMP as for effectiveness and security. Copyright (C) 2011 John Wiley & Sons, Ltd.