In cryptography teaching process， classical password is based， so all cryptography to grasp classical password is particularly important Based on the classical password difficult in the process of teaching， from the viewpoint of teaching， developed a simple understandable cryptography teaching demonstration software respectively， the three classical password - shift password， single table substitution code and replace the password - encrypt &decrypt The three password encryption process of single-step demo; For decryption process， shift password using exhaustively law cracked， single table substitution code and replace the password using statistics Through this software， learners can well master three classical password encryption and decryption 看看吧 不知道对不对
