With a private cloud you still leverage the capabilities of cloud storage like multisite replication, location-aware delivery, and disaster recovery. With a storage cloud, you can insure that your latest training video could be distributed to your employees worldwide, and that playback would come from the closest geographical server. For example, if you had a storage pod in the United States, Europe, and Asia, you could make sure that the training video was streamed to the European viewers from the European storage pod.
In addition to capturing all the benefits of a public storage cloud with a private storage cloud, you also can customize it to your specific needs. Many of the public clouds are generic in their architectures because they need to appeal to a broad range of customers. In the enterprise you may have a specific requirement that a generic cloud service may not be able to provide and since you own that cloud you can modify the architecture to suit your needs.
For example, if you were designing a private cloud and your company was in the oil and gas sector, you might be more concerned about fast ingestion rates. Again, because it is your cloud, you can change the architecture specifically in your cloud to handle that requirement, in this case adding more nodes that are dedicated to ingestion. Alternatively, if you were concerned about a power efficient, dense, and high-capacity disk-based archive architecture, then you could design your cloud utilizing high capacity SATA drives on a system that understands how to use power efficiency to spin down or even power off drives. Lastly, if you wanted to deliver streaming video you would focus more on geographic distribution of your cloud resources and the ability to deliver that video, not only rapidly but at a consistent level as the number of viewers increase.
A private cloud will most likely be less expensive over time. Clearly, the upfront cost will almost always be more expensive, but most private clouds will become less expensive than contracted outsourced solutions after a few years. The driver is typically how much storage are you going to put on the cloud and how much interaction with that storage is there going to be.
Of course, the downside to a private cloud is that you own it. You have to buy much of the capability upfront, you have to maintain it and upgrade it in the future. The suppliers in the space make entry easy by offering solutions that can start very small and scale in very granular increments. It is the classic in-house vs. outsource decision that IT professionals are all too familiar with. Smaller organizations may never recoup their investment. If you can't see yourself ever filling up the initial storage provided by a private cloud supplier, then you probably should lean toward a public cloud service. Larger organizations will have to "do the math" to see what makes the most sense for them.
Cloud computing and cloud storage isn't limited to something that uses the public Internet to make connections and cloud architectures can provide more than just broad access, they can provide distribution, disaster recovery, and with a finely tuned private cloud they can provide power efficiency, density, or high-speed ingestion.
In a future entry, I will discuss suppliers of solutions for designing your own private storage cloud.
George Crump is founder of Storage Switzerland, an analyst firm focused on the virtualization and storage marketplaces. It provides strategic consulting and analysis to storage users, suppliers, and integrators. An industry veteran of more than 25 years, Crump has held engineering and sales positions at various IT industry manufacturers and integrators. Prior to Storage Switzerland, he was CTO at one of the nation's largest integrators.