Cloud computing Service Models

Cloud computing is based on service models. These are categorized into three basic service models which are -

1. Infrastructure-as–a-Service (IaaS)
2. Platform-as-a-Service (PaaS)
3. Software-as-a-Service (SaaS)

Anything-as-a-Service (XaaS) is yet another service model, which includes Network-as-a-Service, Business-as-a-Service, Identity-as-a-Service, Database-as-a-Service or Strategy-as-a-Service.

The Infrastructure-as-a-Service (IaaS) is the most basic level of service. Each of the service models inherit the security and management mechanism from the underlying model, as shown in the following diagram:

Cloud Computing Service Models

1.INFRASTRUCTURE-AS-A-SERVICE (IAAS)
IaaS provides access to fundamental resources such as physical machines, virtual machines, virtual storage, etc.


2.PLATFORM-AS-A-SERVICE (PAAS)

PaaS provides the runtime environment for applications, development and deployment tools, etc.

3.SOFTWARE-AS-A-SERVICE (SAAS)

SaaS model allows to use software applications as a service to end-users


Benefits

Cloud Computing has numerous advantages. Some of them are listed below -

• One can access applications as utilities, over the Internet.
• One can manipulate and configure the applications online at any time.
• It does not require to install a software to access or manipulate cloud application.
• Cloud Computing offers online development and deployment tools, programming runtime environment through PaaS model.
• Cloud resources are available over the network in a manner that provide platform independent access to any type of clients.
• Cloud Computing offers on-demand self-service. The resources can be used without interaction with cloud service provider.
• Cloud Computing is highly cost effective because it operates at high efficiency with optimum utilization. It just requires an Internet connection
• Cloud Computing offers load balancing that makes it more reliable.