IDEA : International data encryption Algorithm (IDEA) is symeteric key encyrption algortihm Idea Algorithm operates on 64-bits (4 Words of 16 bits) using 128 bit key. Plan words are pass through 8 round modules connected serially and last transformation module to produce the cypher text. Each roundmodule consist of combination of xor, adder, modulo multiplers. Roundmodule takes the modulate the keys (6x16bit) on input word (4x16 bits) and prepare the words for next module or tranformer module. Cypher text is recovered by using same Key.