In this paper we have introduced a new symmetric key cryptographic method called Modern encryption Standard (MES)-II. One of the authors have published Modern Encryption Standard Version-I(MES-I). In the present method there is a use of Modified generalized Vernam cipher method with feedback with different block size from left to right. The entire content of given data is divided in different block sizes. After that entire content is divided into two files and then combine them by taking 2nd

more »

... f first and the 1st block. The generalized modified Vernam Cipher method again applied from left to right with different block sizes. The authors have proposed the present method and it can be effective to encrypt various types of plain text files and the method is free from standard cryptography attacks namely brute force attack, known plain text attack and differential attack. MES-II can be used as independent encryption algorithm to encrypt any short message such as SMS, Password or encryption key etc.