The Study Of Secure Localization In Wireless Sensor Networks

As a new frontier science and technology, a new information access platform, Wireless sensor network with its high efficiency, low energy consumption, self-organization, able to work under harsh natural environment, etc., are more and more attention and become a research hotspot in recent years.Node localization is one of the key issues in Wireless sensor networks, Common target tracking, to find the best route, to build the network topology, load balancing, all this need the help of location information of nodes in the network. But the reliability of the existing localization algorithm for sensor network is not good, because it was limited by the conditions constraints of sensor nodes energy and hardware resources. Nodes in the localization process is vulnerable to attack from within and outside the network, leading to the node positioning accuracy reduce, damage applications of the entire network. Based on the analysis of sensor nodes positioning technology research and for their shortcomings, propose two new node security localization algorithm.(1) Reference-weighted security location based on RSSI The traditional RSSI algorithm systems are strongly influenced by the environment, poor ability to adapt to the outside environment and does not have security. Considering the above-mentioned shortcomings of the traditional algorithm, we proposed the reference-weighted security location based on RSSI in this paper. The algorithm in the calculation of the distance in unknown nodes and beacon nodes, set the nearest beacon node away from the unknown node as the reference node, Calculate the distance of the unknown node and its surrounding beacon nodes, combined with triangular position and the position of center of gravity method to get the final coordinates. Simulation results show that the algorithm nor only to improve the measurement accuracy but also enhance the algorithm's adaptability in different environments, against some common attacks, such as the increase of noise in channel, increasing the transmission power, wormhole attack, node capture attack And so on.(2) Bilateration security location for encryption and certificationIn practical applications, in addition to the natural environment, it is also common to come from deliberate human attack and destruction. For the defect of the Reference-weighted security location based on RSSI, Prior to the localization, the unknown nodes need to select the nearest anchor node as it reference node to build a wireless signal attenuation model for current environment. Therefore, once the selected reference node under attack, and broadcast the wrong location information to the whole network, local positioning system or even the entire network will fail. Combined with knowledge of information security, the paper propose a symmetric key cryptosystem based on encryption and authentication security localization. The basic principle is that when the unknown node measure the distance of the surrounding anchor nodes, could be the implementation of Bilateration localization algorithm, according to the algorithm to calculate the location of all the reserve collection, and elected the reasonable position, to get the final coordinates. Simulation results show that, base on the encryption and authentication, introduction of a bilateral security measure Bilateration algorithm significantly improved the safety and positioning accuracy of the original algorithm. Meanwhile, it enhanced the network node localization of the defense capabilities and improve the robustness.