In this algorithm we use the concept of random function for encrypt and decrypt the image using blowfish Algorithm. At present the need of information security has become a necessity. Random number generator (RNG) is widely used in cryptographic system as the cryptographic keys generator. These keys are the most important component in thesystem since the security of the cryptographic system relies entirely on its quality. This algorithm will be used as a variable key size up to 448 bits Latest mitigation techniques proposed at register-transfer level for dependable cryptosystems deal with time redundancy in an active on-line error-detection scheme. Round-based block ciphers are very likely to be hardened with these techniques. With this approach, attackers must face two trouble:dealing alongside on-line error detection and flouting the obligation locale in the round sequence. PRNG will produce disparate repetition sequences for the rounds of the cryptosystem, making extremely tough to associate output data alongside inoculated faults. © 2015 International Journal of Pharmacy and Technology. All rights reserved.