Research On Secure Problem Of Network Coding

Theory and application of network coding rise a hot research in the communications community recent years. Network Coding has broken the traditional routing store and forward mode which is out of any operation on information, and it improves the throughput of network, load balancing and robustness significantly. The secure issues of network coding have aroused controversy since the birth of network coding, attracting more and more attention of researchers and scientific institutions. However, many methods improve security with a huge reduction in the transmission efficiency of the network, which is contrary to the original intention of network coding. The proposal of weak security alleviates this dilemma. It improves the security of network coding and ensures the transmission efficiency of the network, maintaining the original network, which becomes another research area quickly.The main contents of this thesis are as follows:Firstly, start with the proposal of network coding and introduce the secure issues of network coding. Secondly, some researchers have proposed "weak security" during the study of secure issues of network coding, and describe the advantages of weak security. Finally, the research direction of this thesis is stated.In order to improve the security of network coding, stream cipher of cryptography is used to prevent eavesdropping and error correcting code is utilized to prevent contamination.The combination of both can reach the goal of preventing from eavesdropping and contamination simultaneously. The source transfers information to the sink achieving weakly secure requirements, where an attacker can eavesdrop on any channel of the network and tamper with specified number of bits. Simulation results show that this method enhances the security of network coding greatly with an extra short time, protecting the information well,compared with the conventional network coding.This thesis aims to reduce the bit error rate of network coding in the specific channel environment. Simulation results show that the proposed scheme can improve the security of network coding under different conditions in various channels.