ness model, cloud can be categorized to be private cloud where the data and processes are managed within the organization; public cloud where the resources and applications are provided/managed by a third-party off-site provider; and hybrid cloud where both internal and external cloud providers exist. 2.1.2 Types of Clouds Originally synonymous with public clouds, today cloud computing breaks down into three primary forms: public, private, and hybrid clouds. 1 Each type has its own use cases and comes with its advantages and disadvantages. Public cloud is the most recognizable form of cloud computing to many consumers. In a public cloud, resources are provided as a ser- vice in a virtualized environment, constructed using a pool of shared physical resources, and accessible over the Internet, typically on a pay-as-you-use model. These clouds are more suited to companies that need to test and develop application code and bring a service to market quickly, need incremental capacity, have less regulatory hurdles to overcome, are doing collaborative projects, or are looking to outsource part of their IT requirements. Despite their proliferation, a number of concerns have arisen about public clouds, including security, privacy, and interoperability. What is more, when internal computing resources are already available, exclusive use of public clouds means wasting prior investments. For these reasons, private and hybrid clouds have emerged, to make the environments secure and affordable. Private clouds, can be defined in contrast to public clouds. While a public cloud provides services to multiple clients, using a shared infrastructure, a private cloud, as the name suggests, ring-fence the pool of resources, creating a distinct cloud platform that can be accessed only by a single organization. Hence, in a private cloud, services and infrastructure are maintained on a private network. 1 Some add a fourth type of cloud, called community cloud [17]. It refers to an infrastructure that is shared by multiple organizations an