Cloud is an arising and a massive technical development of this modern era which offers variety of services to satisfy the needs of multiple users. Cloud technology has various advantages such as high availability, storage, fast data retrieval, it still has a limitation to overcome which is known as security. Ciphertext Policy Attribute Based Encryption is a proficient technique for addressing this security issue, in which the owner of the data will create a control structure for encrypting the

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... information. Decryption is possible when the peculiar attributes of the users satisfies that access control tree. Private keys for the users will be generated based on the attributes of the users. Another aspect to be considered in this technique is key escrow problem where single third party authority has the ability to decrypt the ciphertext which might contain sensitive information. In order to overcome this problem multiple authority CP-ABE is introduced. In the proposed scheme key generation for the users will issued by separate key generation authority and attributes of the users will be managed by attribute management authority. So none of the authority can decrypt data holder's secret information. Authorities cannot pool data so the collision attack is not possible. Illustration of the proposed technique follows in the later sections of the paper.