Research On Key Management And Data Encryption In WSN

Wireless sensor network (WSN) is an important research direction in the field of information science and technology and has good application prospects in the military, transportation, medical treatment and so on. Due to many influence including bad working conditions, wide distribution, limited energy and small memory, key management and information encryption technology which are lightweight, low power consumption and can meet the security requirements have become important research directions in WSN. Key management is the foundation of encryption technologies and authentication technologies. Group key management is an important research result at the aspect of reducing the cost of sensor nodes in key management in recent years. And recently in the field of WSN encryption technologies, chaotic encryption technology has become hot spot for its low algorithm complexity, fast encryption speed and less storage consumption. In WSN which has lots of sensor nodes and limited resources, security protocols of low consumption are essential. So the research on group key management algorithms and encryption algorithms which are high security and low consumption has vital significance.This thesis firstly introduces the general key management algorithms and the encryption algorithms. On the basis of summary of current research situation of the key management algorithms and the encryption algorithms, this thesis proposes improvement schemes for the key management algorithm using ECC with grouping cluster and the block encryption algorithm based on logistic map. The main innovations in this article are as follows:(1) In key management, this thesis choose a good practical key management algorithm -a key management algorithm using ECC with grouping cluster -to further study, analyzed the application shortcomings in WSN, pointed out the security issues and power issues of using single link to distribute keys in the key updating process and existing foreword security issues in new nodes joining process. For the above shortcomings, this thesis proposed an improved algorithm and made comparative analysis with the original algorithm at the aspects of security, energy consumption and memory consumption, finally proved that the performance of the improved algorithm has improved.(2) In information encryption, this thesis researched the existing chaotic mapping algorithms, analyzed the reasons of inherent short-cycle phenomenon causing weak keys in chaos map, and then pointed out that the methods of disturbing initial value xO and parameter u could reduce the influence for the performance of random sequences, proposed u-perturbation logistic map and tested the random performance. The test result proved the rationality of improved algorithm.(3) Finally, on the basis of the u-perturbation logistic map, this thesis researched chaos encryption system, introduced the principle of the block encryption algorithm based on u-perturbation logistic map and used a chosen plaintext attack to break out this algorithm successfully. According to the principle of the cracking out, proposed an improvement scheme by cipher-text feedback to increase plaintext sensitivity and improved shift algorithm to resist exhaustion attack. At last, this thesis tested the performance of the improved algorithm at the aspects of security, plaintext sensitivity, key sensitivity and encryption time consumption. The text results proved the performance of the improved algorithm had great improvement.