Ask someone what the difference between a private and public cloud is, and most will probably elicit a somewhat confused expression.
With that in mind, I thought I’d elaborate a bit on some of the key attributes and differences for each. Part 1 will focus on the private cloud. Next week’s posting will concentrate on the public cloud.
In brief, a private cloud usually means a reserved space in a data center, with lots of racks full of computers, possibly surrounded by a gate to isolate them from the rest of the datacenter.
This basically means that the company has moved its data center to a remote facility rather than keeping it on premise. The advantages are many – a data center requires redundancies for Internet, power, fire emergency and it requires adequate access control. Putting together a dedicated data center for one company is very costly. It is not just the cost of the infrastructure necessary to support the mentioned redundancies; it is also the cost of setting up the necessary access procedures and controls, keeping a log of such accesses, ensuring procedures are followed and protocols are met. Then, getting certifications (such as SAS70) adds to the costs.
Delegating this to a company that does it as its only business means sharing these costs with all the other customers, and obtaining a far stronger infrastructure for a fraction of the cost. You get multiple internet links coming in each on a separate pipe, and using BGP you are guaranteed an up time of 99.99% without too much effort. You get multiple UPSs, not just one, each fed by multiple, cross connected power sources. You get multiple power sources, generators always on standby, and guaranteed gasoline refills. Usually these facilities are on the emergency refill list just after hospitals and few other high emergency facilities. And they are hosted in bunker facilities not easily expunged. Finally, security is strict, adopting a mix of bio and badge technologies, keeping logs of who walks in and out and when; checking people’s bags for content; tracking closely which hardware is brought in or removed. Some of these facilities may also have DOD clearance.
The cost of hosting a company’s infrastructure in such a center is lower than building it from scratch, and the results are better. Today the cloud term is used and abused, and many companies have taken to calling this solution the private cloud. They are no different than they were a few years ago. Only the terminology has changed.
The introduction of virtual solutions has changed the way this private cloud is structured internally and probably allowed the reduction of space and increased companies’ savings; but the substance remains the same.