Key Management Scheme Of Wireless Sensor Networks Under Energy Constraint

Wireless sensor networks(WSNs)are made up of many small sensor nodes that are capa-ble of sensing,computing,and transmitting data from harsh physical environments.Based on its good distribution characteristics,WSNs are widely used in areas such as position sensing,environmental observation,and medical monitoring.Unfortunately,the batteries get depleted at a faster rate because of the computation and communication operations they have to perform,which results in great challenges in key management of WSNs.Therefore,the research on the key management scheme of WSNs under energy constraint is one of the hot issues.The dissertation firstly proposes an energy harvesting and recharging method for sensor nodes using solar energy to maintain the WSNs battery's lifetime.When the energy of nodes is below the threshold,the source and relay nodes have the ability to harvest energy from the sunlight available and use the harvested energy to transmit and forward the information to the next hop.According to the energy harvesting and recharging experimental investigation,the minimum energy harvested in an area of 1 square meter per day is approximately 48KJ and the maximum energy approximately 84KJ,which indicates the good stability of the proposed energy harvesting and recharging in the WSNs.The dissertation also proposes an energy efficient clustering routing protocol based on the improved low-energy adaptive clustering hierarchy(LEACH)protocol.In the improved LEACH,cluster heads are selected in a cyclic manner,and the energy load of the entire net-work is preferentially distributed to sensor nodes with more residual energy,so as to achieve reduce network energy consumption and improve the network life cycle.The dissertation simulates the improved LEACH in terms of the throughput,delay,and the number of dead and alive sensor nodes.The lifetime of the first node dies within the WSNs for the improved LEACH is increased by 5 times the original LEACH.This indicates that there is a major improvement of energy consumption from LEACH to the improved-LEACH,which leads to the increment of the WSNs lifetime.In addition,this dissertation proposes a key management scheme based on quantum cryp-tography and logic gates.It adopts the Einstein Podolsky Rosen Paradox pair allocation strategy to overcome the susceptibility caused by malicious nodes and uses Toffoli and Peres reversible logic gates to reduce the energy consumption of WSNs.As the qubits stored in a sensor node can be used only once and cannot be duplicated,the risk of information leakage is reduced even if the node is compromised.The research results show the proposed scheme ensures both the secure key sharing and reduced energy consumption of WSNs.In summary,this dissertation focuses on the key management scheme in WSNs under energy constraint and proposes the energy harvesting and recharging method for sensor nodes by using the solar energy,the energy-efficient routing protocol based on the improved LEACH,and the key management scheme via quantum cryptography and logic gates.The experimental results show the effectiveness,theoretical significance,and practical value of the proposed methods.