Abstract

A Wireless Sensor Network (WSN) is a network of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data to the main location. The first wireless network that bore any real resemblance to a modern WSN is the Sound Surveillance System (SOSUS), developed by the United States Military in the 1950s to detect and track Soviet submarines. Currently, WSN are viewed as one of the most important technologies for the 21st century [1]. European Union supports programmes connected with WSN utilization and China have involved WSNs in their national strategic research programmes [2]. The commercialization of WSNs are also being accelerated by companies [3]. As the WSN are part of variety complex systems, it become important to ensure security of these networks. Copying the best practices from the conventional networks is not practical as sensor nodes are subjected to severe limitations of their resources and cannot afford running sophisticated security mechanisms which are often significantly resource consuming. To cope with this problem, the concepts of trust and trustworthiness are employed. Trust management provides for distinguishing between trustworthy and untrustworthy nodes which enables collaborative decisions leading to isolation and exclusion of the nodes with a very low level of trust. It allows to improve the security of the network using fewer resources comparing to security mechanisms used in conventional networks. It this dissertation a new trust management method for distributed wireless sensor networks called WCT2M is presented and its performance analysed. It is explained how WCT2M works in the network applying the fully synchronized sleep scheduling pattern. Such networks were subjected to the analyses with the help of a specially created laboratory and a dedicated WCT2M simulator. The results of conducted experiments allow to ascertain, that the proposed method reliably and efficiently recognizes untrusted nodes and prevent information from these nodes to spread in the network, using reasonable amount of resources.

Author (1)