A Secured Message Transaction Approach by Dynamic Hill Cipher Generation and Digest Concatenation

Abstract

transaction system is a set of participants and their interactions towards an efficient and secured exchange of message between the participants. A secured electronic message transaction system has been designed, developed and implemented where Hill Cipher Cryptosystem is used as the encryption-decryption process with dynamic keys. For this process, any transacted message is to be inputted into the proposed system, and then a matrix of the message length is calculated with its inverse matrix. The calculated inverse matrix is sent to the receiver where he/she used it as the key for the cryptosystem. The key matrix and the Hill Cipher technique have been used to generate the cipher text. The message digest algorithm MD5 operations have been used on the message to generate the digest of the message. The generated digest is concatenated with the encrypted message and is sent to the destination. In the receiver end, the intended receiver first computes the digest of the message by performing the message digest algorithm MD5 and compares it with the received digest that establishes the data integration and non-repudiation of the proposed system. The receiver then decrypts the received encrypted message using the Hill Cipher technique with the received inverse matrix and retrieve the message properly which establishes the message confidentiality and authentication. The proposed system has been implemented using the Java programming and analyzed for several applications. Finally, the fundamental security services have been measured and analyzed. This may be applicable for cryptographic applications.