What is some interesting information about "Cloud computing"?

The definition of cloud computing is shown in the Wikipedia link below.


It also states that clouds have five essential characteristics:


on-demand self-service


broad network access


resource pooling


rapid elasticity


measured service





To a business it is like contracting out a service. Instead of the business providing their own water supply or electricity, it is purchased from an expert provider. That is called a utility service. The business arguments are similar to those used for leasing and contracting out other services. "Leave the services to expert providers, while we concentrate on our core business". That means that capital is not tied up with providing a service which is possibly better provided by a shared system, where flexibility is available. The service can be increased or decreased readily. You pay for what you use.





Many aspects of cloud computing already existed, but should not be confused with it:





Self managing systems. A basic example is automated software updates.





Client-server applications. These the client tells the server what it wants. The server send the result. A lot of interactive stuff on the internet is this way. Yahoo Answers I guess.





Distributed or grid computing. An example is the SETI system, where many computers processed tasks handed out by a centralized server, and return the results.





Mainframe computers. The centralised system - users interact with it, and it provides heavy duty resources. In the past the user just had a terminal., not a computer.





Utility computing (service for a fee). Pay for 1GB of storage, or providing an on line service. This can involve distributed computing too.





Peer to peer systems. e.g. sharing resources of those involved as in file sharing with Limewire, BitTorrent etc. In this case, those who download find themselves also serving files to others)





Looking at the above it is easy to see that there is a lot of overlap with each other and that cloud computing is not all that different to utility computing if you look that up. It is a method of selling mainframe style resources, which often had reserve capacity most of the time. My own first contact was through Open Source software (Open Office) and Sun Microsystems/Oracle has an interest in this with their production of mainframe computers and data base software. Others are Amazon (they started it all), Google, IBM, Microsoft, but that is not a complete list at all.





Look up the Key Features in the Wikipedia link.





I expect this will have a significant impact on IT services, with some changes to "who does what". In other words, some will gain from the shift in thinking or use, some will lose. A paradigm shift maybe.