What is Cloud Computing?

In today's world, Cloud Computing is not an unfamiliar term for a computer and technology literate person. We are living in the world of technology and cloud computing is a new era technology. Pick up any tech magazine or surf any technology tutorial blog, you will get cloud computing everywhere. The biggest problem with this technology is that everyone has a different scenario to define it. If you consult with ten different professionals on cloud computing, surely you will get ten different answers and it is obvious because in computer industry, every new thing is welcomed with warm and open heart. Once Oracle CEO "Larry Ellison" said -

"The computer industry is the only industry that is more fashion-driven than woman's fashion."

Overview of Cloud Computing:

Cloud Computing is a style of computing which provide a facility to make dynamically scalable and often virtualized resources available on the internet as a service. It is a hardware based service which offers compute, network and storage capacity. Main benefit of cloud computing is to reduce the cost of IT infrastructure because it is virtualization based technology.

In other words, Cloud Computing can be defined as a technology which facilitate ubiquitous computing, convenient and on-demand network access to a shared pool computing resources with the minimal management effort from the user side and minimal service provider interaction.

Diagram shows the architecture of cloud computing:

History of Cloud Computing:

It is a general question which is asked when anyone introduce with a new technology. Question like "when was it invented" is obvious.

The term cloud computing is taken as a metaphor for the internet. Internet is represented in the form of a cloud like structure in network diagram. Generally when we think about cloud computing, we think that it is a 21th centaury technology but it is not the whole truth. The concepts of cloud have existed from many years. Let's take a look on them.

Early ages: In 1950's, with mainframe computers:

When the mainframe computers invented, they were very costly and space occupying, it was not possible to buy them for every user because of the cost, space and maintenance issues. The only solution was to provide shared access to a single resource.

In 1970's : With Virtual Machine:

This was the year 1970, when the concept of virtual machines was created. It makes possible to execute one or more operating systems simultaneously in an isolated environment with the help of virtualization software like VMware. It took shared access mainframe to a next level and facilitate multiple distinct computing environment to rely on one physical environment.

In 1990's : with Virtual Private Network:

In 1990's, when telecommunication companies started to provide virtual private network helped the concept of virtualization. These newly offered virtual private network connection provided the same quality as their dedicated service and also reduced the cost. It also reduced the cost of physical infrastructure and provided shared access to the users with the existing physical infrastructure.

Evolution of Cloud Computing:

This is evolution process of cloud computing.

Grid Computing: Grid computing is a collection of computers in a parallel way to solve the large problems. It is like a distributed system with no interactive workload.

Utility Computing: In utility computing, the service providers provide computer resources and infrastructure management when the customer needed and charge accordingly.

SaaS Computing: It is a network based subscription to application. It is also known as "On-demand software". It is accessed by users using a thin-client via a web browser.

Cloud Computing: You can access anytime, anywhere IT resources, It will be delivered dynamically as a service.

If you talk about present time, you will find that SoftLayer is the one of biggest provider of cloud computing infrastructure.

Advantages of Cloud Computing:

Cloud computing provides a lot of benefits to users as well as organizations of all sizes.

1. It is probably the most cost efficient method to use, maintain and upgrade. If you compare its cost with traditional desktop software system, you will get it more economical and efficient.
2. It provides you almost unlimited Storage capacity.
3. Recovery and backup is fast because all the data is stored in cloud.
4. Lower IT infrastructure and maintenance cost.
5. Reduce software cost.
6. Increased accessibility at anytime, anywhere makes your life much easier.
7. More elasticity: It can be scaled to meet all your demand changing with time to time.

Disadvantages of Cloud computing:

1.Security and Privacy: It is the biggest negative issue with cloud computing. Because, it provides a remote cloud based infrastructure so there is always a possibility of data leakage.

2.It requires a constant and high speed internet connection.