is this how the cloud works?
 

Hi, I would like to get a better appreciation of the capabilities of the cloud for business purposes. I'll try and pose an example for comments.

Say I am a C++ programmer. Typically I maintain a version of the software tree on my PC and synch this to our internal network as required (the master). Compilations are done on my PC with a local version of the compiler. If I need to access doco I have LibreOffice on my PC and can access docs on the network (or I could copy them to my PC).

Let's move everything to the cloud. I come to work and click on the Citrix (whatever) link on my desktop. This takes me to my virtual logon. From here I maintain a version of the software tree in a virtual area and synch to the master in cloud as required. I use a cloud version of C++ to compile the files. If I need to access doco I have LibreOffice on my virtual PC and can access docs on the cloud (or I could copy them to my virtual area).

Firstly is that a good example of the cloud (I know solutions are scalable, this is probably a complete package)? Second what performance hits/misses does this present? Maybe compilations would be faster as the cloud solution may provide more grunt. How about overall access? I can't imagine that the cloud would beat access to a wired PC but can the response time be comparable?

Actually, just to push this a little further is this right:

• IaaS – the hardware on which the cloud software runs
• PaaS – the operating system on the hardware in the cloud
• SaaS – the storage and applications (C++ compiler, LibreOffice) in the cloud

I would be interested to know whether my understanding is correct

Cheers

"Cloud" is a marketing term for services located on remote servers. AFAIC, there is no one "how the cloud works," because the term, like many marketing terms, is ultimately without substance.

IaaS is software hosted _somewhere_, that allows you to run machines upon request, providing you with compute (cpu+ram), storage and networking resources. Basically, instead of buying hardware, you're just saying I want X amount of CPUs, Y amount of RAM and Z amount of disk space, and I don't care where and how it works. You get a virtual machine, container or a physical machine, based on what you pay for, but none of the hardware will be yours, nor should you care, just pay as you go.

PaaS isn't an OS. It's a platform on which your apps run. If you use java it'll likely be jboss or tomcat or somesuch, if you prefer python you'll get django or pylons, in short, this is an application framework exposed to you as the client, whereas you don't care about the hardware, hosting, SLAs etc, you just pay to have access to a platform on which you can develop, deploy and run your apps.

SaaS are apps, usually not even developed by yourself. gmail for example is email software as a service. You pay to have email working, and you don't care where and how it is hosted, who and how manages the hardware or the OS and software, all you want and get is just the software's user end, and perhaps an admin panel.

You forgot DNaaS (/Dev/Null as a Service) :)