In this video we going to talk about cloud computing now most of us are familiar with the concept of
running an operating system on a P.C..
So as an example I've got a Windows 7 P.C..
This is a Windows 7 operating system installed on a physical server.
I'm connecting to that Windows P.C. using Microsoft remote desktop and I'm using a Mac for these recordings.
So I've got a Mac and I'm running Janus 3 as an example locally on my Mac.
Now in the same way that operating systems are installed on laptops and PS servers in the past we have
physical pieces that you would install operating systems on and you would run applications on individual
physical servers.
So as an example if you wanted a e-mail server you would order a physical server you'd install the Windows
operating system and then you would install exchange and configure Exchange to give you email if you
wanted to file server you would order a physical server then you would install Windows on it and then
you would store your files on that physical server if you wanted a web server you would order a third
server install an operating system such as Linux or Windows on that server and then run a web server
using ISIS or Apache.
So in the past companies had physical servers and in many cases it was one server per function if you
needed a file server an email server a web server a database server etc. you would buy a physical server
per application and if you needed more capacity you would buy more physical servers.
Now in many cases that's inefficient.
Not all applications require all the memory and all the CPSU on a physical P.C. all the time.
So for a number of years there's been a trend to virtualization.
In other words you virtualize the operating system in what are called virtual machines rather than running
individual operating systems on bare metal or physical pieces.
You run operating systems in virtual machines and you host multiple servers virtually on a single physical
server.