Data Security Protection in Cloud Computing by using Encryption

Cloud computing is a paradigm for offer information technology services on the Internet, such as hardware, software, networking and also the storage can be accessed anywhere at any time on a pay-per-use basis. However, storing private data onto servers of the cloud is a challenging matter. Therefore, cryptography technique and authentication are used in this model to ensure confidentiality and proper access control of sensitive data. Therefore, in this paper I proposed a model to protect data in cloud computing. In this model the algorithm of the RivestShamirAdleman (RSA) is applied to the private data. Furthermore, the protocol of Challenge-Handshake -Authentication-Protocol (CHAP) is used to improve the security of the authentication as well. The results show this model is secure and practical.


Introduction
Cloud computing technology is a model for enabling network access to a shared set of computing resources (e.g., Servers, networks, applications, services, and storage) [1].
It has become a popular topic of research. In general, a cloud computing is another important service after electrical, gas, water and telecommunication services [2].
Cloud services consist of three types of services: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). IaaS Cloud providers offer physical, virtual computer and extra storage networking devices. Example of IaaS includes Amazon Elastic Compute Cloud (EC2), [3]. PaaS, users can deploy applications over the cloud-computing infrastructure, without controlling it. Instead of supplying services, the providers offer libraries and tools to deploy the application itself. Example of PaaS the Google Apps Engine [4]. SaaS provides an application development service to customers either as a service on demand. Example SaaS Salesforce.com, Customer Relationship Management (CRM), Google Docs and Google Gmail. [3].
Cloud services can be classified according to different deployment models, public cloud, private cloud, hybrid cloud and community cloud. A public cloud which is developed by a cloud service provider, public cloud is available to all end users. A private cloud which is developed by a particular organization for their personal uses.
A hybrid cloud is used to make organization scalable. Any private cloud can be extended to public cloud in a hybrid cloud. Several organizations combine to form their private cloud in a community cloud [5].
Move into cloud occurs because cloud computing allows users to access applications from anywhere at any time online [6]. Storing the data in the cloud computing offers to users the convenience of access without requiring direct knowledge the deployment and management the hardware or infrastructure. Cloud is more powerful than persona  [7].
Therefore, security is considered the key requirement for cloud as a robust and meaningful solution. These risks were motivated us to think about a solution to protect data stored in cloud computing. Therefore, data security protection model has been presented in this paper.
The rest of my paper is as follows: Section 2 contains the related works. Section 3 includes the cloud security. Section 4 defines the proposed scheme. Section 5 demonstrates the experimental results. This paper concluded in Section 6.

Related Works
With regard to the importance of data security in the cloud, numerous models presented to improve the reliability and efficiency in cloud computing environments.
Guojun W. And et al. Proposed a hierarchical attribute based encryption (HABE) system by merging (HIBE) system and (CP-ABE) system, to offer access and a good performance. And then, they proposed system by applying (PRE) and (LRE) to the HABE system to revoke access from users [6].
Joseph K. L. And et al. Proposed system with issue revocability for cloud storage.
This system lets a correspondent to send an encrypted letter to a receiver. The sender just knows the individuality of the receiver. The receiver has two things to decrypt the letter. The initial is the top-secret key stored in the computer. The other is the security device that joins to the computer. If this device is missing, then the device is cancelled. This process can be completed through the cloud computing server that immediately executes algorithms to modify the existing ciphertext. The cloud computing servers can't decrypt ciphertext at any time [8].

Security of Cloud Computing
In our life data plays a significant role. It is formed from several sources such as persons, devices, etc. Therefore, we deal with an important matter, that affects all science [11]. Security of data and trust problem have always been the key and challenging matters in cloud [12]. At risk of data abused exists when many users share resources. Accordingly, the data necessity be secured to avoid this risk.
The cloud security includes three important requirements it is confidentiality, integrity and availability.

Confidentiality
Weaknesses must be checked to certify that data is protected from attacks.
Consequently, security test must be finished to protect data.

Integrity
Users must worry about the integrity of data. Since confidentiality does not indicate integrity. For confidentiality purposes, data can be encrypted, however, users may not

Availability
It is the most significant matter in numerous organizations that facing the stopped as a key matter [13].
Consequently, to enhance the security in cloud computing the encryption algorithm and authentication model are suggested as solutions in this paper.

Proposed Scheme
In this work, I proposed "data security protection in cloud computing by using encryption" to protect the sensitive data in the cloud.

Sub-parameters of the proposed system
The security of the proposed system is accomplished according to following subparameters:

Authentication
It is the process of proving a user's identity. Therefore, by using the authentication the proposed system increases the rate of resistance against users unauthorized. In cloud computing model, the Challenge-Handshake-Authentication -Protocol (CHAP) is an authentication protocol used to authenticate the individuality of customers.
Challenge-Handshake-Authentication-Protocol confirms the individuality of the client by using a three method:

CONCLUTION
In this paper, I proposed a solution to cloud storage security problems in terms of confidentiality, availability and integrity to protect the data stored in the cloud. In this model, the RSA algorithm is applied to the sensitive data. Furthermore, I used authentication protocol to improve the security of the authentication. The stored data use encryption and only the authorized user can access the data. Even if unauthorized users reach the data, they cannot decrypt these data. In the future, other algorithms can be used to protect the data stored in cloud computing.