A practical solution to digital communication media exchange by using DES together with RSA algorithm.

摘要

With the ever-increasing flow of information on electronic highways, the need for secure and private communication is taking center stage. Whether it be the electronic transfer of money, the transmission of commercial information, or electronic mail between friends, senders and receivers need to know that others cannot intercept or read their messages or transmit false messages in their place. Secure communications becomes a legitimate need of individuals. This thesis project has two main objectives. First, it compares the advantages and disadvantages for both DES and RSA. Second, it constructs a combined DES and RSA algorithm which has all the RSA algorithm's positive features and the DES algorithm's speed. This provides a practical technique in cryptography that can be used in the area of information secrecy, authentication, digital signature and digital certificate.