환경 감시 센서 네트워크를 위한 저에너지 고신뢰성 라우팅 프로토콜

Abstract

Wireless sensor networks(WSNs) consist of numerous sensor nodes equipped with a radio transceiver, a small microcontroller, and non-rechargeable batteries. The nodes are deployed over a large area and communicate with each other via wireless links. It has been widely recognized that energy-efficient and security are important design issues in WSNs. The disposable sensor nodes with non-rechargeable batteries have serious energy constraints and, thus, the energy-efficient and energy-balanced design of protocols is necessary for prolonging network lifetime. On the other hand, security-sensitive networks such as military applications, the interception of information can cause serious problems. So it is important to ensure that the data arrive at their destinations safely and reliably. For energy-efficient networks, dynamic clustering is an effective technique to prolong network lifetime, achieve scalability, and balance load, which are important requirements. When this method is applied, however, some nodes consume energy unnecessarily because the environment is such that the data collected from the sensor nodes often overlap. Moreover, this unnecessary energy consumption increases energy consumption at the cluster-head node. Thus, such a protocol must change the cluster formation and cluster-head node in each round to prolong the network's lifetime. Nevertheless, this method also consumes a lot of energy during the set-up process of cluster formation. To cope with such problems, we propose a novel cluster-based protocol. For secure communications in cluster-based sensor networks, key pre-distribution methods using a polynomial key pool are more suitable than other methods to guarantee reliable and stable operation. With this method, however, some nodes cannot join each other because of the probability of pairwise key establishment. Moreover, a hierarchical structure requires a differentiated security level in each part. To cope with such problems, we propose a key management method with an authentication method. In this study, we propose an energy-efficient and reliable routing protocol for environment monitoring sensor networks to prolong the network's lifetime. First, we propose a clustering method that reduces unnecessary data transmission among nodes by eliminating the duplication of data. Our method alleviates the problem of nearby nodes collecting the same data from adjacent areas by electing all the nodes that form a cluster with consideration of their sensing coverage. Furthermore, it introduces relay nodes, also called repeaters, which help to hop the data transmission along to cluster head nodes in order to cope with energy-hole and link-failure problems. This method prevents data loss caused by node link disconnections, thus it collects the data reliably. Second, to achieve a secure network, we propose a key management scheme that is appropriate for hierarchical sensor networks. Our proposed scheme is based on the polynomial key pool pre-distribution scheme, and sustains the network's stability through a key authentication process. According to the performance analysis results, ARCS reduces the energy consumption and increases the transmission efficiency of; consequently, it prolongs the network lifetime by about 61%, 49%, 36% and 21% compared to LEACH, TEEN, APTEEN and ARCT, respectively. The simulation and analytical comparison results show that the proposed scheme has higher resiliency than key pool, grid and location-based schemes, and it provides an authentication method.