Justin Davies' Blog

Grid computing is scalable (that is, make it big or small according to your needs) computing power, usually used by businesses. And supplied via the web. Cloud computing is a method of supplying technology on demand. Who cares where it comes from, or even what it’s called? So long as it’s there when you need it. That’s why services as basic as web-based email are also forms of cloud computing.

Cloud Computing v. Grid Computing: the chicken or the egg? I’m guessing it’s actually a matter of ‘who cares?’ Although some purists might gnash their teeth to hear that!

But if I had to answer it, I’d say it’s not actually a question of what came first. It’s more a question of which is a subset of which.

In my opinion, grid computing is a kind or subset of cloud computing. Grid computing is scalable (that is, make it big or small according to your needs) computing power, usually used by businesses. And supplied via the web.

It’s a way of tapping into extra computing power in ‘times of need.’ Say you need to do a mass mailout of a large document once a month (think: a pdf newsletter). Just tap into the power of someone else’s grid for the day and off it goes in the blink of an eye – rather than tying up your servers for the next 12 hours. Of course you pay for it. AAmazon Elastic Cloud Compute offers this service (although they seem to be hijacking the name cloud computing), as does GoGrid (who are, btw, not affiliated with GoPC).

All very interesting, but how does this relate to cloud computing?

Some would have you believe that cloud computing is either a fancy name for, or a part of, grid computing. Others go into infinite detail to categorise various providers WITHIN the cloud computing realm. (Actually, we think cloud computing encompasses grid computing, but that’s beside the point.)

This is because cloud computing as a term is still up for grabs. Purists can argue until they’re blue in the face, but the fact is that cloud computing will encompass whatever the people say it encompasses. Whatever works best and hits the market first and touches the public heart in the most widespread manner.

Best to keep definitions broad, then. Cloud computing is computing power offered via the web - something you can tap into without knowing or caring how it works. You just want to know THAT it works. And therein lies the principle of cloud computing.

Services, platforms, power, apps, hosting, etc you can pick out of the cloud that is the internet. A cloud is fuzzy, misty, obscure and opaque - but that’s okay because it’s not about how or why it works. It only matters that it works and you can access it anywhere, anytime.

Cloud computing is a method of supplying technology on demand. Who cares where it comes from, or even what it’s called? So long as it’s there when you need it. That’s why services as basic as web-based email are also forms of cloud computing. It’s just that, as the services expand, we are now finding it necessary to have a name for this stuff. And just in time, because the expansion it’s undergoing is nothing short of phenomenal.

• Did Google's Eric Schmidt Coin "Cloud Computing"?
• Cloud Computing vs. Grid Computing - What's the Difference?
• Cloud Computing vs Grid Computing
• Cloud Computing - The User-Friendly Version of Grid Computing