SECURE DATA SHARING FOR MOBILE CLOUD COMPUTING USING BLOWFISH ALGORITHM

Abstract : Cloud computing is a great innovation in the world of computing, there also exist downsides of cloud computing. These most important challenges are security and privacy of data on the cloud, check availability of data on the cloud. For these problems, data storage security refers to the security of data on the storage media. Security is an important factor in cloud computing for ensuring clients data is placed on the secure mode in the cloud. The third party must not be stealing data so authentication of client becomes a mandatory task. Security is very essential for applications where the sensitive Aminimal key size and minimal computations have to be selected as energy efficiency is also a limitation of mobile applications. Therefore, there is a great need of encryption method with high levels of security and with minimal key size. Traditional symmetric or asymmetric encryption algorithms can be used for cloud computing to provide three cryptographic primitives, integrity, confidentiality and authentication. There are many drawbacks for symmetric encryption algorithms such as key maintenance is a great problem faced in symmetric encryption methods and less security level is the problem of asymmetric encryption methods even though key maintenance is easy. And there are many drawbacks of asymmetric encryption algorithms such as those algorithms consume a significant amount of computing resources such as CPU time, memory, and battery power. Therefore, the main target for ensuring security is to develop new hybrid cryptography protocol. This new security protocol using combination of both symmetric and asymmetric cryptographic techniques is proposed by merging both symmetric and asymmetric techniques by a way that avoids the disadvantages of the existing hybrid protocols. We developed five new hybrid cryptography protocols for achieving security in mobile cloud computing. In proposed protocol, the plain text is divided into two parts, the first part is encrypted using encryption scheme and the second part encrypted using another encryption scheme. These two schemes have occurred simultaneously so that the time required for making encryption to all plain texts is small because the two schemes are parallel. We can obtain much security with a little time in this proposed protocol. The proposed protocol achieves the security services such as authentication, confidentiality, integrity, non-repudiation and availability. The results show the superiority of NHCP algorithms over other algorithms in terms of the encryption and decryption times, processing time, and throughput.

 EXISTING SYSTEM :

 In straightforward integration method Storing data in a third party’s cloud system causes serious concern on data confidentiality. In order to provide strong confidentiality for messages in storage servers, a user can encrypt messages by a cryptographic method before applying an erasure code method to encode and store messages. When he wants to use a message, he needs to retrieve the Codeword symbols from storage servers, decode them, and then decrypt them by using cryptographic keys. General encryption schemes protect data confidentiality, but also limit the functionality of the storage system because a few operations are supported over encrypted data.

 DISADVANTAGE :

 And there are many drawbacks of asymmetric encryption algorithms such as those algorithms consume a significant amount of computing resources such as CPU time, memory, and battery power. Therefore, the main target for ensuring security is to develop new hybrid cryptography protocol. This new security protocol using combination of both symmetric and asymmetric cryptographic techniques is proposed by merging both symmetric and asymmetric techniques by a way that avoids the disadvantages of the existing hybrid protocols. We developed five new hybrid cryptography protocols for achieving security in mobile cloud computing.

 PROPOSED SYSTEM :

 We proposed the hybrid approach18 to integrate ECC and Blowfish algorithm to provide data security to mobile users. Blowfish sub keys are stored in memory of smart phone, which is prone to unauthorized access. If we use randomization at every encryption and decryption, then it will be very difficult for third party to decrypt it. Stored Blowfish expanded 18 sub keys kept secure by XOR ing plain text with random number16. Number of rounds of Blowfish is minimized by using random number.

 ADVANTAGE :

 The proposed hybrid cryptography algorithm is developed to secure the data and information which is transmitted through the cloud. The aim of the hybrid cryptography algorithm is to efficiently encrypt and secure the transmitted data. Eight encryption algorithms were implemented in the proposed hybrid cryptography algorithm. Five of these algorithms are hybrid and implemented to improve the efficiency of the encryption algorithm time and security. Using the hybrid algorithms improves the security of the encryption algorithms since the data is encrypted using more than one algorithm and at the same time minimizes the time taken by the algorithms that take much time to encrypt the data.