SeNsIM-SEC: Security in Heterogeneous Sensor Networks

Wireless sensor networks are widely used in several application domains thanks to their data acquisition and processing capabilities and their decentralized and self-organizing nature. A widely distributed monitoring system is typically characterized by the need to integrate a large amount of data; if considering complex critical environments such as hospitals, these data often have different security requirements, to be addressed by means of specific security protocols and architectures. In such a distributed system, security must be addressed at different levels, namely the physical node level, the inter-node communication level, and the application level. In this paper, we focus our attention on security problems related to the data exchange between sensor nodes and propose an hybrid cryptosystem based on Elliptic Curves, aimed to ensure confidentiality, integrity ad authentication requirements to the inter-nodes communication. The integration issue has been addressed by proposing an extension of the SeNsIM integration platform, in order to enable the management of heterogeneous networks having different security requirements. At this aim, we have developed a flexible wrapper to connect the whole system to the secured network, and carried out a performance analysis of the overhead introduced by security mechanisms, showing the feasibility of the proposed cryptosystem and the platform scalability and extensibility features.