Everyone must have heard about cloud computing or the Cloud in this tech-world. But some people dont know what is cloud computing exactly. In simple terms, cloud computing refers to applications and services offered over the internet. Such services are collected from data centers all over the world through the web and this intangible but universal nature of the internet got the name cloud.
Cloud computing has some of the concepts of distributed, grid and utility computing. But this similarity may be due to technology changes, usages and implementations over many years. In place of conventional data pipes, routers and servers, a cloud has now services. Even if the hardware and software part of networking is still present, for building up applications, higher level service capabilities are used. An application in the cloud is built using the resource from multiple services from multiple locations. The cloud itself provides the available resources to the end user. Behind the service interface, a grid of computers is present to provide the resources. Thus, in essence this is distributed computing.
Cloud providers are generally grouped into three categories: software-as-a-service providers like RightScale, infrastructure-as-a-service vendors like Amazon that provide Web-based access for storage and computing power and platform-as-a-service vendors like Google that offer tools to build and host web applications for the developers. An application or a service developer requests access from the cloud rather than a specific endpoint or named resource. Thus, a cloud manages multiple infrastructures across multiple organizations and many frameworks are tried together.
Even though there are many positive aspects for this field, vendors are facing criticisms regarding many issues. Privacy is the prior issue as a cloud model can be easily monitored lawfully or unlawfully by the companies hosting the cloud services control, thus affecting the communication and data storage between the user and the host company. The security of cloud computing services is another major issue that may be delaying its adoption completely. The servers can be affected by external environmental conditions, sustainability of cloud computing is regarded as fluctuating, yet another issue.
