Data Storage Security in Mobile Cloud Computing (MCC) using Improved Blowfish Algorithm

Mobile cloud computing (MCC) combines cloud computing and mobile computing to deliver vast computational resources to mobile consumers, network operators, and cloud computing providers. You may access your data from anywhere in the globe using any mobile device that is linked to the Internet. Cloud computing provides access to data in real-time whenever and wherever want. Any conventional mobile device can benefit from MCC's infrastructure, computational capacity, software, and platform services. Network security, web application security, data access, authentication, authorization, data confidentiality, and data breach are all concerns of MCC's security. Because mobile devices lack sufficient storage and processing power, their data storage capacity is limited. Users of mobile devices may inadvertently provide sensitive information over the network or through the application. Therefore, data security is the main concern for mobile device users. The objective of this paper is to find a solution that can enhance technical requirements with relation to user’s data security and privacy in mobile cloud computing. To achieve this improved blowfish encryption algorithm is used to encrypt each user’s data security and where the shared secret key is hash down using message digest called secured hash function. Hashing can increase the integrity and privacy of user data. The proposed algorithm is evaluated with a normal blowfish algorithm and 3DES with different parameters. Improved blowfish algorithm shows better performance than normal blowfish algorithm and 3DES. In this work, we have developed web-based application where the Amazon MySQL RDS database is used for data storage.


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computing has arisen to overcome the constraints of handheld devices. It mixes cloud computing and mobile computing. The concept of mobile was presented not long after cloud computing was launched in mid-2007 [2]. Mobile cloud computing has attracted the attention of a large number of industrialists because it lowers the cost of developing and running mobile applications.
With modern smart phones and powerful mobile devices, mobile apps provide many advantages to the community but it has also grown the demand for online availability and accessibility. Cloud computing is provided to be widely adopted for several applications in mobile devices [3].
Data replication, consistency, restricted scalability, instability, unpredictable availability of cloud resources, portability (due to a lack of cloud provider standard), trust, security, and privacy are all issues in the field of mobile cloud computing [4].
Dr. U S Pandey's 2018 research report is the first thing that motivates us. It shows that data security and privacy, user authentication and authorization, and user access in mobile cloud computing are all hot topics in research these days. This is because once data leaves the protected environment of mobile devices; it is exposed to a variety of harmful threats both on the device and in the cloud.
The second thing that motivates us to undertake this work is the fact that mobile cloud computing advantageous computing choice for businesses, organizations, institutions etc. Still the security challenges for this technology are not addressed adequately. Because of this reason, we chosen this research work and make contribution to this research area.
The rise of mobile cloud computing has not been accompanied by an increase in consumer trust in cloud-based data management in various industries. Because of the hazards of confidentiality and privacy, several businesses are hesitant to utilize cloud computing mobile services [5]. Therefore, data security is the main issue that should addressed. Confidentiality and massage integrity among them requires high guaranteed security. MCC inherits all of the security challenges associated with cloud computing, as well as the resource constraints imposed by mobile devices. Due to resource limits, the security methods proposed for the mobile cloud-computing environment cannot be directly run on a mobile device. A lightweight secure framework that delivers security with the least amount of communication and processing overhead is required for mobile devices [6].
There are different security algorithms are used to encrypt data store. These are asymmetric and symmetric. Asymmetric encryption techniques are slower than symmetric encryption techniques because they require more computational processing capacity [7]. Therefore, we prefer to use symmetric algorithm since mobile device have low processing unit and storage space. There are different security algorithms are DES, AES, 3DES, Blowfish Algorithm.
In this work, we select symmetric algorithms, which have high performance, high speed, and which keep data confidentiality and privacy. Therefore, we choose blowfish algorithm, which is fastest symmetric encryption algorithm.
The main objective of this work is to secure data stored on cloud by mobile device using symmetric cryptographic algorithm called Improved blowfish algorithm.

II. LITERATURE REVIEW
Cloud computing is a term used in computer networking to describe many computing ideas that involve a large number of machines connected by real-time communication, such as the internet [8], [9], [10]. Cloud computing is also known as distributed computing via the network, which refers to the capacity to run a program or application on multiple computers at the same time.
They define mobile cloud computing and present a summary of the findings from this review, focusing on models of mobile cloud applications, in [11]. Mobile user authentication strategy for mobile cloud computing in this paper [14], which is based solely on Different security mechanisms used in mobile cloud computing and their efficiency were addressed in [15].

The security and privacy of data kept in Cloud
Computing is a complex issue with critical implications. To guarantee safe connection between the user and the cloud, cryptographic techniques were used. To guarantee safe connection between the user and the cloud, cryptographic techniques were used. It examines the differences between symmetric and asymmetric algorithms. Showed that symmetric encryption has the speed and computational efficiency to handle encryption of massive volumes of data in cloud storage, and that DES is a better encryption algorithm. However, DES takes longer to encrypt data and has a lower throughput than other symmetric encryption algorithms.
The Internet and network applications are rapidly expanding. As a result, the importance and value of data shared over the internet is growing. In data communication, information security has always been a major concern. Any loss or threat to information can result in a significant financial loss for the company. In information security systems, encryption plays a critical function. This study compares and contrasts four of the most widely used symmetric key algorithms: DES, 3DES, AES, and Blowfish. The following factors were used to make a comparison: round block size, key size, encryption/decryption time, CPU process time in terms of throughput, and power consumption. These findings suggest that blowfish is a better option than AES [16].
In terms of encryption time, decryption time, and throughput in wireless networks, this paper [7] provided a fair comparison of AES, DES, 3DES, and

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The goal of the research work explained in [21] is to show how to ensure mobile data storage privacy and secrecy in a cloud communication environment using mobile training datasets and the Training dataset   For any record system, we have used the following step to store and retrieve their information. The admin accept any file from the mobile client that is authenticated and encrypt the file using improved blowfish algorithm and store in the cloud. The clients decrypt their file using the key generated by sever and file id then view their file. There are three steps for proposed system they are explained below.

2.
The server generates random key or one-time key.

3.
The server encrypts the file and store encrypted file to specific location and required data to the database (name of the file, type of the file Since it uses same key it need more protection from hackers and attackers. Therefore, we prefer to encrypt the generated key using massage digest, which call secured hash function. Using massage digest can increase integrity. The key generated is hash down to 160 bit by using massage digest and prepare long bit encryptor. Then p-box and s-box is initialized the process is gone until get the encryptor. After getting encryptor, the encryption process is starts. When encryptor is gain, automatically random long independent variable is generated that is unique for every cipher text. A decryption process is the same as encryption process only reverse order. Below the three processes, give encryption decryption process using proposed algorithm.
Process 1: Setup Encryptor using secret key Step 1. Get secret key Step 2. Hash down the key to 160 bit key by using Message digests and returns byte data key.
Step 3. Initialize p-box and s-box Step 4. XOR the byte key over the p-box Step 5. Encrypt p-box and s-box with all zero string Step 6. Return Encryptor 106 Process 2: Encryption Step 1. Generate random independent value(IV) Step 2. Allocate byte with size of original data plus 8 byte padding Step 3. Copy all bytes of the original data in to a buffer of type byte Step 4. Get Encryptor generated in the above process while generating secret key Step 5. Step 6. Combing the buffer byte data Step 7. Return binhex cipher data by converting the byte to binhex.

Process 3: Decryption
Step 1. Get the number of estimated bytes in the binhex cipher text Step 2. Make sure size of the text is equal to block size Step 3. Get the independent value(IV) from the cipher by converting the binhex to bytes Step 4. After getting the independent value (IV) and bytes buffer do the same as Encryption but the p-box value in reverse order.
Step 5. Return the string by converting the byte array to UNICODE string Model of the proposed system is to encrypt any file accepted from the client using blowfish algorithm. Then the file converts in to cipher coded file this cipher coded file. This cipher coded file is decrypted using the hashed secret key to get the original file. Blowfish are evaluated considering the following parameters • Key size in bits.
• The time consumption signature generation and verification. Figure 4 Sample key generation

C. Results and Analysis
In this research work, developed a prototype of data security for mobile cloud computing using improved blowfish cryptographic encryption algorithm. The mobile device users are able to store file without any fear any attacker. Since the proposed system can give privacy, confidentiality secure for any users that store their file on cloud. The table 1 give the sample file stored in the database that is encrypted and stored and the secret key that is hashed and store on the cloud that generated by the sever during file uploaded.        shows that normal blowfish algorithm is better than DES but less than the improve blowfish algorithm.

V. CONCLUSION
Mobile cloud computing is one of the fastest-growing cloud computing environments in worldwide which able to access anywhere, any time by the mobile device user. Even though it has a huge advantage, it has also security threats that should be addressed.
Data security has a great role from the security issue raised on mobile cloud computing since most the client data store on the cloud.
In this research work, proposed a solution that allows data to be secured by implement improved blowfish cryptographic encryption algorithm to encrypt any file upload by mobile device user and store on the cloud. Using improved blowfish with encrypted key can increase the security able to fulfil the all security principles such as privacy, confidentiality, integrity.
Our proposed work only allows the authorized user can access their data. An attacker cannot decrypt the data until it gets the encrypted secret key and file id that is generated by the cloud server.