Thanks to Microsoft’s Windows 7 commercials, the term “cloud” has moved into the mainstream.Most people understand that “cloud” refers to applications that stream from the Internet. But there’s a lot more to it than that.
The word “cloud computing” covers a bunch of technologies, which is why Forrester Research can say that the cloud was a $40.7 billion market in 2011 and will grow to a whopping $241 billion in 2020.
A quarter of a trillion dollar market? Wowzers.
Microsoft says the cloud will create 14 million jobs by 2015, too.
But, truth be told, most folks still don’t completely understand what the “cloud” is. So let’s fix that …
What does the term “cloud” mean?
The “cloud” is an umbrella term used for a whole bunch of things, most, but not all, having to do with getting software or computing resources delivered over the Internet as a service. These services are usually paid for on some kind of usage or subscription basis — a certain dollar amount per resource (like data) consumed, or per month. Stop paying, and service is cut off. This is different from buying a software product and getting to use it forever.
Where did the term come from?
Back in the day, network diagrams used the cloud icon to indicated the public telephone network and later the Internet. At the time, it really meant “out there, out in the messy world, on someone else’s systems, out of my control.”
So the cloud is really just another term for “Internet” right?
No, not really. It is possible to use the Internet without using cloud services and it is possible to be on a cloud without being on the Internet. For instance, you could use the Internet to download some software from an application developer, send an e-mail, and connect remotely to your files stored on your office service, all without using “cloud” services.
What are the different technologies that are considered cloud?
Ah. Here we get to the techie, wonkie stuff. Essentially there are five buckets of things called cloud.
- Software as a service (SaaS): This is an application delivered over the Internet as a subscription. It is not installed on a company’s servers or on a person’s PC. Salesforce.com is the granddaddy of this category, but other examples include things like Google Apps, Microsoft’s Office 365, or the human resources suite Workday. When the term “cloud” is used for consumers, it typically means SaaS such as Dropbox, iCloud, Evernote, and so on.
- Platform as a Service (PaaS): This is the next layer up, where you want to build your own cloud application but you want to rent everything you need including the runtime platform like Java, Ruby or .Net. Examples of PaaS include Google App Engine, Microsoft Azure, and Salesforce.com’s Heroku.
- Infrastructure as a Service: This is the most basic cloud of them all, where you rent the hardware (server with operating system, storage, and networking) and you upload your own applications. The difference between IaaS and old-school hosting is that you are sharing the hardware with other renters (in geek terms: it’s a multitenant environment). You only pay for the computer resources you use. Amazon AWS is the biggest here, but Rackspace is another and Linode is popular for Linux users.
- Private clouds: Here’s where things get tricky. Private clouds don’t necessarily use the Internet. This means an enterprise has built its own version of a public cloud to use for itself. When enterprises remodel their IT systems to be like a multitenant environment, they can become more efficient.
- Hybrid clouds: This means that a company is choosing to store some of its applications in its private cloud and using a public cloud for spill-over. A retail company could, for instance, rent extra space on an IBM retail cloud in December when transactions spike. In the old days, a company would have to buy more servers to be ready for those spikes, even though they would sit unused for 11 months.
What’s the big deal about cloud computing?
Because companies share the infrastructure, cloud computing makes it super cheap for anyone to access enormous computational resources. Rather than spending thousands to own your own computer and networks, you can rent all the power you want for however long you want it.
This has lead to a boom in innovation. Companies can grow really big before they need to invest in their own data centres (Groupon started on Amazon), or they can quickly expand by putting a new service in the cloud. Examples include Pinterest, which uses Amazon Web Services, and LivingSocial, which uses Rackspace.
Does everyone love the cloud?
Hardly. Enterprise IT folks are still a little suspicious of the cloud — and the lack of control it represents. But they are getting over it. They are being won over by the number of cloud products, their low cost, improved security and management controls.