Key Aggregate Cryptosystem for Data Sharing in Cloud Computing

Now a days cloud computing is becoming the famous area for researchers. Because it is very important in data sharing methodologies. The data being shared inside the cloud must be secure, flexible and efficient. For this purpose we describe new algorithm which depends upon public key cryptography and produce constant size cipher text. These ciphers can be decrypt by using a secret key. This secret key can release the constant size aggregate key for selection of flexible choices of ciphers. The other encrypted files except these cipher remain confidential. The obtained aggregate key can be send to others or can save into a card in very secure manner.