Research On Key Management And Broadcasting Authentication Protocol In Wireless Sensor Networks

Wireless Sensor Nerworks (WSNs for short) is the combinative production of computation, communications and sensors. Recent advancement in wireless communications and electronics have enabled the development and application of low-cost, energy-efficient and multi-function wireless sensor networks. These micro-sensors usually have data acquisition unit, process unit and data transfer unit. Wireless sensor networks are made of by Thousands and thousands of sensor nodes like that, whose applications include military affairs, habitat monitoring, medical treatment, smart home and other areas.In some applications such as military and business, since the aggressors are not allowed to know the data sampling and transmission process, the secure issue is critical. Besides some common properties with Ad hoc network, WSNs have their own characteristics described by follows: Firstly, the network has the larger scale of network and more sensor nodes; secondly, the network is easy to produce topoloby inconsistence and single node failure; thirdly, the power of the node is supplied by battery, and the capability of computing, storage and communications is feeble.Currently, WSNs face great challenges in security because of those characteristics metioned above. And most of traditional secure protocols and protect mechanisms are not fit for WSNs.This dissertation studies the security mechanisms for WSNs from the following two aspects: key management and broadcasting authentication mechanism. It classifies the current key management schemes into four kinds, respectively according to the dependent cryptograph basis, network logic topology structure, whether updating the keys periodically and the degree of key connectivity in network. Some typical schemes are introduced and their advantages and defects are pointed out through performance comparison among them. And then, two novel key management method are proposed, one is based on special data structure named key relation table and the other lies on peculiar logic grid topology. Security ananlysis of these two schemes is illustrated while computation, storage and communication performance comparison is provided with some famous schemes such as method based on logic key tree structure and SPINs etc. The second study addresses on broadcasting authentication mechanism in WSNs. uTESLA, multi-level uTESLA and their improved protocols are emphasized in this desetation. A new broadcasting authentication protocol deduced from uTESLA is presented who is based on parent-tree clustered construction, and as an improved result, called by HW- uTESLA, which contributes from several aspects: the broadcasting scope, dropping delay and Hash key chain renewed resource, etc.At last, agent-oriented middleware of WSNs is introduced. Meanwhile, security management module of DisWare has been designed and implemented including encryption/deciferment, authentication and key management functions.