Design And Implementation Of BigNum Network Coding Security Mechanism In Multipath Transmission

In order to improve the communication stability in complex environment,scholars proposed a multi-link fault-tolerant transmission method using Big Num network coding based on intelligent network architecture,and proved that it can effectively improve the communication stability in complex environment in simulation environment.Big Num coding based on multipath transmission has good practical value in complex environment,and its potential needs to be further explored.Existing research for multipath transmission network coding of Big Num focuses on how to improve communication stability in bad environment of the channel such as high packet loss rate,or properly schedule data sent policy over multiple links to improve data throughput,moreover data transmission mechanism is studied to reduce the impact of data disorder on communication efficiency in multipath transmission.Most of the above studies are based on the purpose of improving communication efficiency.In this paper,Big Num coding is regarded as a new communication method that can be improved.On this basis,a security mechanism is designed and implemented to make it as a new data encryption method,which is more efficient than the traditional DES encryption and can resist the pollution attack against part of the data.The security mechanism of this paper aims at two security threats,eavesdropping attack and pollution attack.In this paper,the advantages and disadvantages of four coding matrices(random number matrix,generation matrix,lower triangular matrix and diagonal matrix)in security and efficiency of eavesdropping attack are analyzed,and a new coding matrix is redesigned on this basis.Coding is equivalent to encrypting information.The attacker cannot get the plaintext of the message without knowing the principle of Big Num coding or without obtaining the parameters of coding matrix.Then we design the process of synchronizing the new coding matrix at both ends of communication through matrix synchronization message,so that we can change our matrix flexibly according to the change of communication environment at any time,and increase the difficulty of the attacker to crack.Finally,we also make use of the multi-path transmission mechanism such as polling,so that the data is evenly scattered over multiple links,making it difficult for attackers to eavesdrop on continuous and complete data,and further reducing the possibility of eavesdropping on plaintext communication.Aiming at defencing pollution attack,this paper proposes an error detection and correction mechanism using redundant data of Big Num coding.This mechanism can check whether the data is polluted or not in the transmission process,and can correct the polluted data if there is enough redundancy.In this paper,each module is implemented and tested: firstly,the selection of big number library is carried out.Secondly,the four modules of security mechanism proposed in this paper are implemented and tested,and the corresponding functions are verified.Then the time of Big Num encoding and traditional DES encryption is tested and compared.It is proved that Big Num encoding takes about two orders of magnitude less time than DES,so the efficiency is higher.Finally,the simulated attack test of the mechanism designed by us is carried out to analyze the security functions of each module,which proves that the mechanism in this paper can encrypt transmitted data to resist eavesdropping attacks and detect and correct errors in received data to resist pollution attacks.