Mixed random 128 bit key using finger print features and binding key for AES algorithm

Abstract

In the present age, cryptography is being used extensively for protecting information. The process of protecting information by encrypting it into an unreadable format is called cipher text. Only those who possess the secret key can decrypt the encrypted data into plain text. Remembering the key is a very difficult task, due to the usage of 128,192&256 key bits. To solve this issue, biometrics can be used as a key. In this paper a mixed key is generated from the fingerprint and binding key. This increases the complexity of guessing and cracking a cryptographic key. Mixed key will provide good opinion for information security. This combination of biometric key and binding key is done by mixing biometric templates with random number keys. This combination is done by using fuzzy commitment scheme [8]. Mixed key increases the randomness of the key. This implementation is done using MATLAB 7.7.0. Fingerprint images used in the experiments were obtained from the National Institute of Standards (NIST) fingerprint data set. Brute force attack is the main cause for information theft in encryption algorithm. This attack is a dictionary attack mainly depends on the randomness of the key. Random keys are less affected by this attack. The randomness of the generated mixed key is tested using randomness tests. The generated mixed key randomness is compared with the biometric key which is generated from the finger print. The experimental result shows that average of 50% randomness is increased in mixed key when compare to biometric key.