Generalization for Multidimensional Playfair Cipher

Abstract

Playfair cipher is a multi letter, poly alphabetic, symmetric cipher having a 2 dimensional key matrix supporting the security of 26 English alphabets. From the survey it is found that there are other variants which have key matrices with 3 and 4 dimensions. The main aim of this research is to provide the generalization for multidimensional Playfair cipher which includes choosing the dimension based on the number of values/characters supported by the Playfair cipher variant and the corresponding encryption and decryption processes. It is found from the dimensional analysis that more is the dimension for the fixed number of values/characters supported, stronger is the cipher against brute force attack with respect to possible number of groups. Keywords: Information security; Cryptography; Conventional cipher; Classical cipher.