Cloud Computing Layers
To understand Cloud computing, wqe need to understand in details about the three layers of cloud computing. They are:
- Infrastructure-as-a-Service (IaaS) : This layers is also called as Infrastructure service layer. In the instance of IaaS, servers, network devices, and storage disks are made available to groups as services on a need-to basis. Virtualization, allows IaaS providers to offer almost unlimited requests of servers to clients, while making cost-effective use of the hosting hardware.
Companies can use IaaS to build new versions of without having to invest in physical IT assets. Increasingly, organizations are using IaaS to host their websites, monitor their traffic and keep them running, without monopolizing up IT resources. IaaS is particularly beneficial for micro, small and medium-sized businesses that can access server and storage systems, which they would otherwise have to purchase.
- Platform-as-a-Service (PaaS) : This layers is also called as Platform layer. This layer provides a platform for creating applications. PaaS solutions are fundamentally developed platforms for which the development tool itself is hosted in the Cloud and retrieved through a browser. With PaaS, developers can build Web applications without installing any tools on their computers and then deploy those applications without any generalized systems administration skills.
Today, PaaS is being delivered like a utility over the Internet, with corporate IT departments, paying according to usage. Owing to PaaS, there has been a barrier in the number of people who can develop, maintain and deploy web-based applications without requiring specialized skills.
- Software-as-a-Service (SaaS) : This layers is also called as Application layer. This layer includes applications that run off the Cloud and are available to Web users on anytime and on anywhere basis.
Private V/S Public Clouds
The Cloud, apart from its different layers, is also visible through three alternates. There are the public Clouds for instance, a deployment option for initiatives where the infrastructure services are provided by a hosting partner. It is this third party dealer that hosts and manages these offerings.
The other version is the private Cloud, where it is deployed within the initiatives and managed and maintained by the organization itself. A private cloud is a collection of virtualized infrastructure textiles that are coupled with automated management. It is deeply integrated with the application platform and identity, protection and access technologies to create an internal service-oriented environment for initiatives.
Although the private cloud does not offer advantages with the hypervisor capability becoming integral to the operating system, it is becoming increasingly affordable for initiatives.
A more recent, new concept in Cloud computing is the hybrid Cloud, which is a blend of the public and private Cloud. The hybrid Cloud, created by the enterprise, can influence the benefits provided by both public and private Clouds. However, issues related to the sharing of responsibilities between the enterprise and the third party vendor and governing such a Cloud, make it a slightly complex deployment option.