Research And Improvement Of LEACH In Wireless Sensor Networks

Wireless sensor network(WSN) is a kind of self-organizing network madeup of a large number of nodes in the form of wireless communication and it isalso a special form of ad-hoc networks. WSN is the international frontier andmultidisciplinary research hot field nowadays, and is widely used in such harshenvironment and has bright prospects. Routing Protocol is one of the keytechnologies of wireless sensor networks, which determines the path of datatransmission and forwarding. The traditional routing protocols usually do nottake into account security issues and is vulnerable to external network attack.Besides, the network recovery capacity is limited.This paper firstly elaborates the key technologies of wireless sensornetworks, analyzes routing protocols of typical wireless sensor networks andmakes comparison between them, and introduces the commonly seen attackand safety requirements. LEACH is a routing protocol for WSN. Then, fromthe physical model, network model, detailed algorithms of LEACH routingprotocol, this paper makes detailed description of routing protocol, analyzesand concludes the advantages and disadvantages of LEACH routing protocol,and put forward the improvement plan of the wireless sensor networks. First,to deal with the uneven clustering problem, unreasonable cluster head electionproblem of the LEACH routing protocol, this paper raises a self-adaptive gridprotocol clustering algorithm LEACH-EED. Simulation experiment resultsshow that the improved protocol can significantly prolong the survival time ofthe network. Second, as to problems of being vulnerable to attack and weaknetwork recovery capacity, this paper proposes a self-adaptive grid securerouting protocol, LEACH-SEED, based on hash-chain and redundantcontrolling. At first, redundant controlling mechanism is used to improve thecluster head election mechanism. After the completion of cluster head election,q keys are allocated to every cluster head node randomly from the key chainpool composed of hash chains, the other nodes use a one-way hash function and pseudo-random function to generate communication keys. After beingattacked, the network can be recovered from network autonomy and thewaiting cluster head identity number。Experimental results show that theimproved clustering algorithm can effectively reduce the mortality of nodes,enhance anti-attack capability, improve data fusion and extend the survivaltime of networks.