A sensor network consists of a large number of sensor nodes, which are spread over a geographical area. Sensor networks have found their way into many applications, from military domains to traffic or environmental monitoring, and as sensor networks reach toward wide spread deployment, security becomes a major concern. In this regard, one needs to be sure about the confidentiality, authenticity and tamper-proof of data. The research thus far has focused on how to deploy sensor networks so that they can work efficiently; however, the focus of this paper is on sensor networks’ security issues. In this paper, the authors propose a formal model to design and analyze the secure sensor network system. The model is based on an augmented Petri net formalism called Extended Elementary Object System. This proposed secure sensor network model has a multi-layered structure consisting of sink node layer, sensor node layer and security mechanism layer. At the security mechanism layer, a synchronous firing mechanism is utilized as a security measure to detect malicious node attacks to sensor data and information flow. In addition, the model applies SNEP protocol for authentication and confidentiality of sensor data.
Top1. Introduction
Recent advances in wireless communications and mobile computing have enabled the development of low cost, low power, and multifunctional sensor nodes that are small in size and communicate un-tethered short distances. These tiny sensor nodes, which consist of sensing, data processing, and communicating components, form sensor networks (Akyldiz et al., 2002; Levis et al., 2005; Lewis, 2004; Romer & Mattern, 2004). A sensor network can provide access to information anytime, anywhere by collecting, processing, analyzing and disseminating data. Each sensor has wireless communication capability and intelligence for signal processing and data communicating. The positions of sensor nodes can be randomly deployed which implies that the sensor networks are self-organized. They can be easily deployed because no human intervention or infrastructure is needed. Hence, sensor networks can help pave the way for autonomic computing (Wang, 2007).
Although much research has thus far focused on making sensor networks feasible and useful, security has been receiving increasing attention (Karlof & Wagner, 2003; Perrig et al., 2002; Walters et al., 2007). As sensor networks reach towards wide spread deployment in different application domains, security issues become a central concern. Power and computation constraints are often high on the agenda in sensor networks, relegating security requirements to a lesser place. Given the fact that there has not been much attention on formal modeling and analysis of the security aspects in sensor networks and that little prior work exists in this area, we recognize the need to identify potential problems and challenges in the sensor network’s security and propose solution techniques.
Before delving into the specifics in sensor network security, we first examine the security requirements for a sensor network. They include: