Institute of Electrical & Electronic Engineers
There are many security algorithms that are used for security purpose. IDEA is one of them. The block cipher IDEA operates with 64-bit plaintext and cipher text blocks and is controlled by a 128-bit key. The fundamental innovation in the design of this algorithm is the use of operations from three different algebraic groups. The algorithm structure has been chosen such that, with the exception that different key sub-blocks are used, the encryption process is identical to the decryption process. The drawback of IDEA is that the large numbers of weak keys were found in IDEA (International Data Encryption Algorithm). Also a new attack on round 6 of IDEA has been detected.