Modified Multi Way Feedback Encryption Standard (MWFES) Ver-I

Nath et al recently developed a method Multi Way Encryption Standard ver-1(MWFES ver-1[17]). In MWFES ver-1 the authors have introduced a method which is based on introduction of two way simultaneous feedback. In MWFES ver-1 the authors applied feedback from left hand side as well as from right hand side one after the other. The ASCII code of plain text, key and the corresponding forward and backward feedback is added to get some temporary number. The number is taken modulo with 256 to get the corresponding cipher text and also the feedback for the next available column. In MWFES ver-1 the authors did not consider any block size. It was essentially a stream cipher method. In the present modified MWFES ver-I the authors have added some modifications. Firstly the authors have taken a fixed block size for doing forward feedback as well as backward feedback. The initial feedback is calculated from user entered key and also using MSA algorithm. After finishing all blocks if the file contains 2 bytes then also the same MWFES method applied for characters separately and if 1 byte is left then the authors performed simply XOR operations between plain text and the key. After completion of one full round the entire file is reversed and the same feedback method applied using block-size=16. The authors noticed that there is a significant change found in the encrypted text. The authors shows that modified MWFES ver-I is better than MWFES ver-I. The encryption operation was performed n-number of times on the entire file. The decryption process is just the reverse process of encryption. The present feedback method can used be for encryption of SMS, password or any confidential message. The results shows the present method is free from Differential attack, known plain text attack or any kind of brute force attack.