Signature based authentication using contrast enhanced hierarchical visual cryptography

Idea stated in this paper describes the application of hierarchical visual cryptography to the authentication system. This is an alternative approach for fingerprint based authentication mechanism. Fingerprint based authentication mechanism have two major problems: repetitiveness during authentication and non acceptability for some users. In proposed system, the signature of a person is taken as input which is encrypted using hierarchical visual cryptography. HVC divides input signature into four resultant shares. Among four shares, any three are taken to generate key share. Remaining share is handed over to the user and the key share is placed on authentication system. Both the shares appear in scrambled format but upon superimposition, the secret is revealed. HVC encrypts the input secret in hierarchical manner hence more secrecy is maintained in the shares. Shares generated out of this scheme are expansion less. Original secret size is retained while encrypting the secret. While authenticating, user have to produce his/her share to the authentication system. Card reader reads the share and stacks with one which is available in database. Upon stacking signature is revealed and the enrollment number of the share is retrieved indicating that the person is authentic.