Design And Implementation Of Internet Multi-Dimensional Heterogeneous Covert Transmission Channel

With the Internet becoming the infrastructure for building modern information systems,secure communication technologies in the Internet environment have become an important support for ensuring national security,commercial interests,and personal privacy.Traditional VPN technologies based on encryption still face weaknesses such as poor content listening prevention,difficulty in anti-tracking and traceability,and weak resistance to malicious blocking.Anonymous communication networks,by introducing ideas such as onion routing and mixed networks,can hide communication relationships and communication paths,making them better than VPN technology in terms of user privacy protection.However,existing anonymous communication networks lack a good covert access mechanism and are susceptible to traffic entry or exit attacks.This paper conducts research on the covert access problem of anonymous communication networks.The research results have been applied to practical engineering projects and have applied for technical invention patents.The main contributions of this paper include the following aspects:A multi-channel asynchronous transmission model is proposed that separates control flow and data flow.The data transmission process is decomposed into channel establishment phase and data transmission phase.Based on this,further mechanisms are designed for multi-channel transmission,such as data redundancy fragmentation and encryption coding,to ensure communication content security.Compared with traditional synchronous transmission models,this model disperses control message exchange and business data exchange in different transmission channels,making it difficult for network monitors to locate data flows by tracking control flows,thereby enhancing the concealment of the communication process.Experimental results show that this channel model has the advantages of low construction cost,strong scalability,and effective resistance to blocking.A reliable transmission protocol is designed for a multi-dimensional and heterogeneous covert transmission channel model.This transmission protocol is an application layer protocol built on top of the TCP/IP protocol.It is designed to meet the security requirements of covert transmission channels.It provides a detailed description of the format for control flow messages and business flow data packets,while incorporating reliable transmission mechanisms such as channel acknowledgment,proactive retransmission,and request retransmission.These mechanisms support secure,stable,and reliable transmission over multi-dimensional and heterogeneous covert transmission channels.Experimental results show that compared with covert channel technologies such as data steganography,the proposed reliable transmission protocol can achieve efficient data transmission while maintaining high covertness.In the experimental environment,the data transmission rate can reach 760 Kbps.Based on the above technological innovations,this paper has designed and implemented a prototype system and deployed a real multi-dimensional secure transmission channel system in the Internet environment.It can build heterogeneous data transmission channels based on a variety of typical Internet applications.Under the condition of a basic communication bandwidth of 4Mbps,the data transmission bandwidth of a single channel can reach 565 Kbps.The research results of this paper realize efficient data transmission and covert access to anonymous communication networks,which can provide design reference and technical support for building covert communication networks.