Research And Implementation Of Instant Messaging System Based On Tor

The Internet brings convenience and harm to users,and it becomes more and more difficult for users to securely transmit information on the network.As users pay more attention to private data,more and more people begin to use anonymous communication systems.Tor(The Onion Router)has developed into the most successful anonymous communication system by virtue of its good anonymity and the support of many volunteers.Tor realizes the anonymity of communication relationship by encrypting the communication link and message content,but the anonymity design of Tor has an adverse impact on its network performance,and the network performance of Tor is very different from that of ordinary networks.In order to meet the needs of users for anonymous communication,the support of anonymous instant messaging tools is required.Due to the poor performance of the Tor network,the instant messaging experience on Tor cannot meet the needs of users.This thesis focuses on improving the performance of instant messaging on Tor.This thesis analyzes the basic principle of Tor and the influence of Tor anonymity design on its network performance.This paper analyzes the characteristics of Tor network nodes,network bandwidth,network delay and other aspects according to Tor official data.Due to the insufficient performance of Tor network,large text data transmission under Tor becomes the bottleneck of file transmission.In this paper,according to the characteristics of Tor network,a parallel transmission model(segmented parallel transmission model on Tor)SPTM-Tor is designed to solve the problems caused by large file transmission under Tor.SPTM-Tor speeds up the transfer of files on Tor through operations such as file segmentation,parallel transfer,and file aggregation.Experiments show that SPTM-Tor can increase the transmission rate several times and enhance the stability of file transmission.This paper designs an anonymous instant communication model(B/S architecture instant message model on Tor)B/S-IMTor based on the characteristics of Tor network.In order to improve the performance of file transfer in the anonymous instant messaging system,SPTM-Tor is introduced in this model,so that the anonymous instant messaging system based on B/S-IM-Tor has good data transfer performance while satisfying the anonymity.In order to meet the needs of users’ anonymous communication,this thesis designs an instant messaging system model based on the B/S-IM-Tor,and uses this model to design an anonymous instant messaging system.The special network architecture design of this model enables the instant messaging system based on this model to have good performance while satisfying anonymity.After actual testing and use,the system shows good anonymity,stability and immediacy,and can meet the needs of users for anonymous instant communication.