International Journal of Engineering Inventions (IJEI)
Now-a-days, most sensitive information is transferred through the internet. Cryptography is very useful for network security. It consists of encryption and decryption. Using encryption the plaintext is converted to unreadable ciphertext. Format Preserving Encryption (FPE) means during encryption process the format and data type of the plaintext will never change. FPE is a string encryption scheme that made minimum changes to the plaintext. Black and Rogaway constructed three main techniques for format preserving encryption such as prefix cipher, cycle walking and feistel network with cycle walking.