Cloud Service Models - by Nitish and Shobhit

Cloud computing is causing a major shift in IT industry. There are millions of people using cloud computing for different purposes. The best part of cloud is that the user has to just pay for what he is using. Demand for cloud services are different for different users, for example, a company just needs storage and network resources and another needs a complete software application with user interface. Cloud provides different solution to the different types of problems. A cloud can interact with user in variety of ways and we call them service models.

TYPES OF SERVICE MODELS

There are three types of service models

·       SaaS-Software as a service

·       PaaS-Platform as a service

·       IaaS-Infrastructure as a service

SOFTWARE AS A SERVICE(SaaS)

SaaS or software as a service is a service model in which user just have to use a web browser to access the services. The software provided by the vendor have inbuilt programs which resides on cloud with user data. Companies using SaaS do not have to worry about the handling of data, machines or anything. It eliminates the need for in-house data centers, administrative support and data storage. Scalability and metering feature are the best feature as a user have to just pay for what he has used and on demand, services can be increased or decreased.

Advantages of SaaS

SaaS has many advantages and these are discussed below-

·       It eliminates the need of storage devices and other hardware systems.

·       It saves the administrative cost that makes it cost effective.

·       It helps small start-ups as it provides them services at low cost because a small start-up can’t afford costly hardware devices.

·       The service is on demand and the user have to just pay for what he used.

·       User just need a browser to access the service.

·       They provide device independent access to the services.

Disadvantages of SaaS

We have many advantages but the potential disadvantage of this service model is loss of data as application resides on cloud and user’s data too, So, many companies have fear of losing their data as they don't have any kind of control over it.

Examples of SaaS

·       Salesforce.com

Salesforce.com was among the first companies to start cloud based SaaS. They provides SaaS for Customer Relationship Management(CRM).

·      Taleo

Its parent company is Oracle and it provides SaaS for human resources management. It can help companies in recruitments and management of their workforce.

·       Cisco Webex

It is a company that provides softwares for virtual meetings that reduces the cost of travelling, staying at hotels on a business trip

·       Microsoft Office 365

It is a very well known SaaS tool that millions 0f people use around the globe to create, edit, and share the files.

PLATFORM AS A SERVICE(PaaS)

PaaS or platform as a service is a service model in which the user get collection of hardware and software resources to develop the applications and user can deploy them on cloud. The benefit of PaaS is that the user don’t have to buy costly hardware devices and the problem of managing and installing of operating system is also handled by the vendor. Here user get access to hardware devices but they are not residing in the company itself but somewhere at remote place.

Advantages of PaaS

·       Low cost

It decreases the cost as we don’t have to buy heavy hardware systems.

·       Increases efficiency

Developers don’t have to worry about management of hardware and OS, they can invest their time in increasing productivity.

·       Scalability

We can increase or decrease the services as we want.

Disadvantages of PaaS

The disadvantage of PaaS service is the risk of breach by the PaaS provider and it is hard to integrate cloud solutions with legacy software.

Examples of PaaS

·      Google app Engine

Google app engine also known as GAE ,is a PaaS solution that helps developers to create and host web-based applications that reside and run on services managed by Google.

·       Netsuite

Netsuite is a hybrid of SaaS and PaaS. It provides a development environment that sits on the top of the netsuite business solutions. Using a drag-and-drop environment, developers can quickly build and deploy enterprise solutions.

·       Cloud Foundry

Cloud Foundry is the industry-standard open source cloud application platform for developing and deploying enterprise cloud applications.

INFRASTRUCTURE AS A SERVICE(IaaS)

IaaS Or Infrastructure as a service is a service modal in which the user is provided with Hardware resources. In IaaS, it is the duty of client to install and manage the system, which they can normally do over the internet. A company that deploy software needs a specific platform like windows, .NET, and Microsoft SQL server and many other. Using PaaS can eliminate the need of administration and management of OS but some companies want to do it themselves or their product demands so. So they choose IaaS over PaaS.

Advantages of IaaS

·       Easy to use due to the  automated deployment of hardware.

·       Reduction of IT staff.

·       Elimination of an expensive and staff intensive data center.

Examples of IaaS

Microsoft Azure, Cisco Metapod, Amazon Web Services ( AWS ).

DIFFERENCE BETWEEN IAAS, PAAS, SAAS

IaaS	PaaS	SaaS
Short for Infrastructure as a service.	Short for Platform as a service	Short for Software as a service
Provides machine storage, and network resources that developers can manage by installing their own OS, application and support resources.	Includes hardware and software resources both.	A complete software application with a user interface.
Complexity: High	Complexity: Moderate	Complexity: low