What's the cloud anyway? By this post, I attempt to make clear the concept of Cloud computing.
First of all,
It's called cloud computing because the data and applications exist on a "cloud" of Web servers.
Basically, Cloud computing consists of:
1) Servers
2) Databases
3) Softwares
or any Combinations of the above.
It's also called Software as a Service(SaaS) while it is also referred to as Everything as a Service(Eaas).
Cloud computing means that companies, the users of IT services, can buy their IT related services as a service. You don't need to buy servers, software licenses :), et cetera. You or your company can buy them as services.
Its called services because you pay the Service provider based on your usage. Just like you pay your ISP for the data you download/upload or the time you spent(..reminds of the old days of 56KBps. :).
There could be peak hours and off peak hours. During the off peak hours, your resources(if you own them) will be idle and thus can be considered a loss for your company.
On the other hand, with Cloud Computing you don't have to worry about the infrastructure.
With cloud computing, you would pay for peak capacity based on usage.
There are several key characteristics of cloud computing:
1) The customer doesn't have to know (and buy) the full capacity they might need at a peak time. Cloud computing makes it possible to scale the resources available to the application. A start-up business doesn't have to worry if the advertising campaign works a bit too well and jams the servers.
2) Customers pay only for what they use. They don’t have to buy servers or capacity for their maximum needs. Often, this is a cost savings.
3) The cloud will automatically (or, in some services, with semi-manual operations) allocate and de-allocate CPU, storage, and network bandwidth on demand. When there are few users on a site, the cloud uses very little capacity to run the site, and vice versa.
Because the data centers that run the services are huge, and share resources among a large group of users, the infrastructure costs are lower (electricity, buildings, and so on). Thus, the costs that are passed on to the customer are smaller.
Cloud computing is often confused with grid computing. Let me make the distinction.
Grid computing a form of distributed computing whereby a 'super and virtual computer' is composed of a cluster of networked, loosely-coupled computers, acting in concert to perform very large tasks").
Here's an example of the two to make the distinction clearer:
Grid computing: 2 or more servers/computers(whatever u call it) tries to solve a tough problem(like breaking a strong cipher encrypted with a 1024 bit key. (hehe. :)).
Cloud Computing: There is a central system which has access to a number of other systems which provide data only to the central system(There can be many central systems, likewise). An external system queries central system for data, the central system then collects data from the required systems/nodes and then provide back the data to external system who requested it.
Technically speaking, the central system would expose a Web service that external systems can access and get data.
And yeah, this data could be softwares too..!
Hope you got it.
More about Cloud Computing later..
