Desing And Implementation Of Secure Communication System Base On Alliance Chain In Complex Network Environment

As information technology continues to develop,network communication has become an essential part of people’s daily lives.However,various security issues exist in network communication in complex network environments,such as information leakage,data tampering,and network attacks.These issues not only threaten people’s communication privacy and security but also cause serious economic and social losses to society and the country.To address the security issues in communication in complex network environments,researchers have developed various types of secure communication systems.However,traditional secure communication systems are vulnerable to various network attacks due to their centralized nature,making their security difficult to meet the needs of practical applications.To address these issues,this thesis designs and implements a secure communication system based on a centralized consortium chain,focusing on the robustness and attack defense capabilities of the communication system itself.The specific contributions are summarized as follows:(1)From the robustness of the communication system itself,this thesis designs a consortium chain secure communication system based on double public key encryption.To address the anonymity requirement of secure communication systems,a consensus process based on the PBFT algorithm is designed to combine secure communication with consortium chain consensus,allowing each node to participate in the entire consensus process,making it difficult to track nodes and ensuring communication anonymity.To address the security requirements of the secure communication system,a double public key encryption algorithm for information and a node reputation evaluation method are designed to ensure the security of each message content through double public key encryption and local private key decryption and reduce malicious behavior by evaluating the reputation of each node,ensuring system security.To address the performance requirements of the secure communication system,a dynamically adjusted communication topology is proposed to reduce communication complexity and improve system performance by improving the communication topology.(2)From the attack defense capability of the communication system,this thesis studies the anti-attack methods of the secure communication system based on an abstract social network and proposes two anti-attack defense methods,namely,node identification method and overall network evaluation method,using Sybil attacks as an example.The node identification method first judges whether each node is a malicious node based on the random walk and path intersection theory.For nodes that are difficult to judge,their features are identified by the SVM model to output the results.The overall network evaluation method is based on a few known malicious nodes and honest nodes as initialization labels,and the label features are continuously iterated through random walks to spread to the entire network,evaluating the attack probability of all nodes in the network.Through this anti-attack defense method,malicious attacks are identified and evaluated to reduce the harm of network attacks and improve the security and anonymity of the system.(3)Based on the design of the consortium chain secure communication system and the anti-attack method,this thesis implements the secure communication system,introduces the system model and architecture,and showcases the implementation process and key technologies of the system modules.