Coughlin thinks of cloud computing as “an outsourcing for your technology assets”. He further says that “cloud computing is a service in which an internet connected machine and remote digital storage are both used to provide a number of capabilities for both business and personal uses. Technically speaking, he said that there were three types of cloud computing services that are commonly put to use: infrastructure as a service, platform as a service and finally, software as a service. With the first mentioned cloud computing service, Parsik says, clients have access to virtual servers in the third party service provider’s data centre, which can be used any way we want.
In this case users have to install their own software and also be responsible for maintaining it. This option gives the users enough flexibility and scalability says Parsik. Another feature is that if a user needs 3-4 servers to run his systems, and needs 50 during the holiday season, he will not have to buy more servers but can just rent the additional servers on the cloud system. An example of an Iaas is Amazon’s Elastic Compute Cloud, which is also called as EC2.
Paas includes all the features of the Iaas, with clients using the provider’s computing platform including an operating system, developer tools, database and web servers through which users can develop and run their software in the cloud without having to bear the cost and the complexity of buying and then managing the underlying hardware. Paas allows the user better economies of scale with the trade off being that platform provider’s ability to lock down the service so that you can not use your own tools. The Google App Engine, with which users develop and host web applications using Google development tools, is a good example of a Paas.