Article Preview
TopIntroduction
Cloud Computing is an internet based distributed virtual environment. All computational operations are performed on cloud through the Internet (Rawat 2012). It consists of a set of resources and services offered through the internet. Cloud computing is also called Internet computing because they both have same symbolic icon. Applications, Operating systems, data, processing capacity, and storage all exist on the Web, ready to be shared among the users (Sadiku et al., 2014). Cloud computing is basically a collection of different e-resources available twenty four hours and accessible from anywhere through browser software. Many companies are getting benefits from cloud computing due to its pay-as-you-go cost model and elasticity of resources, where users pay for only those services that they used (Prakash, 2013), and cloud provides customizable services to users. Compared to the traditional models which provide in-house infrastructure, cloud provides low cost services with high availability (Li et al., 2010). In cloud model the user is exempted from hardware and software maintenance cost.
The National Institute of Science and Technology (NIST) defines the cloud computing in a more appropriate way:
A model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (networks, servers, storage, applications and other services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. (AlZain et al., 2012)
The cloud computing can be defined in a simpler way: “A distributed virtual environment that provides virtualization based IT-as-Services by rent”. That is it is often better to get the required resources on the rent rather than purchasing one’s own resources. The main purpose for users to avail the cloud services is to avoid IT infrastructure purchasing and maintenance cost to get data accommodatable storage space for their large amount of data in the cloud. Beside all cloud services such as Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS) (Jansen et al., 2011), cloud also provides storage service as a sub-service of IaaS service model. In storage as a service, the distributed database servers are available on rent to store users’ data. These services are available for all kinds of users without any business discriminations.
Cloud computing is facing a number of challenging threats due to its virtualized multi-tenant nature (Purushothaman & Abburu, 2012). Data security is always the main challenging threat to the quality of services in cloud and may suppress the users’ interest to adopt cloud services for their enterprise benefits (Ransome et al., 2010). All integrated and communicated environment business decisions and operations depend on the quality of the data and information risk management (Yanjun & Wen-Chen, 2009), good quality data is required for better decisions (Lam & Chun, 2008).