Using Petri Net for Modeling and Analysis of a Encryption Scheme for Wireless Sensor Networks

Nowadays the wireless sensor networks (WSN) are increasingly being required for applications where the data reliability needs to be duly guaranteed. Due to this, many research works have been directed in this sense. However, WSN security is not an entirely solved issue. The aim on this chapter is to use Petri Nets (PN) to model and analyze the validity of an encryption scheme applied to WSN. Usually the modeling of communication systems can become quite complex, most of the time is necessary to consider a large number of variables and mathematical models to describe them. Nevertheless, structural properties of a system and dynamic characteristics of its behavior can not be properly derived from those models. On the other hand, PN can model dynamic characteristics such as synchronization and concurrency. PN were developed by Carl A. Petri in 1962 as a mathematical tool for the study of communication with automata. Its further development was facilitated by the fact that PN can be used to model properties such as process synchronization, concurrent operations, conflicts or resource sharing and deadlock freedom among others (Reisig, 1986), (Reisig & Rozenberg, 1998). In literature we found works where PN have been used in order to model and analyze several related aspects of a WSN. In (Chen et al., 2008) the authors use PN to determine the minimal necessary number of devices in a coal mine, in order to establish the location of miners in case of accident. There are many works related to power constrains, most recently work (Liu, Ren, Lin & Jiang, 2008) deals with the power saving problem, where the authors have proposed four sleeps scheduling schemes for different sorts of and analyze each of them by Stochastic Petri Net (SPN). By using the steady state probability matrix of the SPN models is obtained the average power consumptions and events delays. Also, there are many references devoted to communication protocols and recently in reference (Haines et al., 2007), PN are used as a formal verification technique of a MAC protocol. Where a case study is presented applying this technique to IEEE 802.11 centralised control mechanisms to support delay sensitive streams and fading data traffic. In reference (Pengand et al., 2007) author have used the PN to model the Session Initiation Protocol (SIP) and accomplished its verification.