Research On Energy-efficient And Secure Routing Protocols In Wireless Senor Networks

Wireless sensor network(WSN) is a wireless network composed of a group of sensor nodes, which are deployed in an ad hoc fashion cooperate on sensing, collecting and processing the information of the covered area and then sending the information to the observer. WSN has wide application potential in military affairs, environment detecting, health affairs, home network and other commercial fields.Due to the limited battery capacity and characteristics of unattended operation after deployment, minimizing energy consumption is a key requirement in the design of sensor network protocols and algorithms. Various energy-efficient routing protocols have been proposed for wireless sensor networks. Data-centric routing is a commonly utilized approach that uses attribute-based addressing to perform the collective sensing task. Directed diffusion (DD) is a robust, scaled, and energy-efficient data dissemination protocol based on data-centric routing, but there are still some shortcomings associated with it. For example, interests are broadcasted in the network-wide range. Every node in the network forwards each new interest message to all of its neighbor nodes. The approach is rather inefficient in the sensor networks where the significant overlap between the neighbors of the two nodes in immediate vicinity can lead to a large number of unnecessary rebroadcasts. This additionally results in increased channel contention and waste of bandwidth that take further toll of the scarce energy resource of the nodes. The network-wide broadcast operations strongly influence the performance of the protocol. We proposed a grid-based directed diffusion inspired. The network area is firstly divided into fixed virtual grids. In each grid, only one node is responsible for broadcasting interest message, and the rest ones receive the interest from it. Due to rest nodes firstly sending data to the header node, more chances are provided to aggregate the redundant data information as early as possible. Simulations show that, utilizing the approach, broadcast overhead and data message are reduced. This results in large energy savings. At the same time, advantages of DD are also reserved.As WSN is usually deployed in open areas, sensor nodes are susceptible to a variety of attacks, such as capture, eavesdropping, denial of services, wormhole, and sybil attack. Along with WSN becoming hot spots in research and industry, the security aspects of WSN attract attentions of both researchers and engineers. According to DD, we analyze the possible attacks, and add security schemes such as secure data aggregation, traffic attack detection and key management to it. Then we perform security analysis and simulation.Firstly, we propose a trust-base data aggregation protocol in cluster. Data aggregation is thought to be one of the main technologies in wireless sensor networks, and can mostly reduce the whole networks'data transmission, save the sensor node's battery energy, and so it prolongs the whole networks'life. But with wireless sensor network increasingly deployed in hostile environment, sensor nodes are easily captured by enemy, the secure keys that data aggregation needs will be revealed. And then data aggregation will be not secure. In this paper, we introduce trust evaluation scheme of neighbors and use the listen mechanism to watch sensor node's data aggregation action. According to the listening result, we use trust mechanism to evaluate nodes'aggregation action, and recognize the captured nodes. Then we elect secure cluster head according to trust evaluation. Secure cluster head evaluates nodes'trust according to their past aggregation result, and performs reliable data aggregation. Simulations show that the proposed trust scheme can effectively deal with the threats of the captured nodes, and ensure the secure of the data aggregation.Secondly, we propose ARMA-based traffic attack detection protocol. In wireless sensor networks, how to accurately and rapidly detect traffic attack, so as to ensure the availability of network infrastructure, is one of the most challenging security problems. This paper proposes a simple and efficient ARMA(2,1) traffic prediction model for sensor nodes based on linear prediction technique. Then a traffic attack detection scheme based traffic prediction, is designed. According different roles of nodes, different monitoring schemes are used. Virtual cluster heads and monitoring nodes are elected to monitor cluster head. Member nodes are monitored by cluster head. Simulations show that the propose scheme can quickly detect traffic attack with less resource overhead, and prolong the lifetime of network.Lastly, we propose security node-based key management. Ordinary nodes and the cluster head node are responsible for data collection and transmission. Security nodes are responsible for key management. In this paper, we describe the formation of security nodes and the cluster head under control of the security nodes. We also describe the formation of foue kinds of key: node key, pair of keys, cluster key and public key. Performance analysis and experiments show that, the proposed key management protocol is superiority in communication and energy consumption. The delay time of the cluster key generation is to meet the requirements. It provides more coordinated and more security authentication key to effective anti-node arrived in the ability to capture. It supports large-scale networks.