When most non-IT people think of cloud computing, they imagine a public cloud. However, private clouds are an option that shouldn’t be overlooked. Here’s a rundown on the differences between a public cloud and a private cloud, and what strengths each offer.

What Is Public Cloud?

With a public cloud, infrastructure is owned by a service provider and shared by multiple businesses. This makes it easy to deploy and scale resources.

A public cloud operates a bit like a public utility, and while it started out with a software as a service model, the modern public cloud can involve infrastructure, applications, or data storage delivered by a third-party vendor.

What Is Private Cloud?

With a private cloud, infrastructure is hosted at your data center or a service provider’s data center. It is private in the sense that the hardware, even though it is not in your office, is entirely dedicated to your business. This makes it easy to customize storage and networking.

A private cloud looks a bit like what we used to call an on-premises data center. The big difference is that you use software, virtualization, and automation to organize like the public cloud but with added data privacy and security.

The two options have different strengths, so here’s how those differences break down.


Private cloud solutions offer a range of customization that the public cloud can’t. Anything that needs customized hardware, like high-end applications, is better suited to a private cloud. With a private cloud, you design the architecture to suit you.


Both public and private clouds are scalable. You can purchase additional capacity as needed. You won’t need to worry so much about headroom when planning IT operations and can make decisions based on business goals instead of IT conditions.

However, the important difference is that your public cloud can be deployed and scale within minutes. If you have a private cloud, it takes a little more time and planning.

Capital Expense

Neither a public nor a private cloud require any capital expense from a customer.

However, the money you’re spending changes with customization. If you go with a customized private cloud, your provider will ask for a time commitment (e.g., one year, two year, three year, etc.).


A private cloud solution offers more in the way of control over security. First of all, a private cloud is managed by your own IT department. As it lives behind your firewall, outside access to your data is limited to your organization.

This isn’t to say that the public cloud has terrible security. It is to say that the public cloud’s security has to accommodate everyone using the public cloud, while a private cloud’s security is specific and customized. It’s important to remember that data must travel through the wild internet to reach a public cloud. Like most differences between the public cloud and a private cloud, the distinction comes down to control.

Data Privacy

Can governments or other actors touch your data? On the public cloud, this is frustratingly muddled, and it depends on the location of your company, the cloud service provider, the servers themselves, and the laws in all those places. The US government, for example, can force Microsoft to deliver data stored on their servers in Ireland without a word from the Irish courts. In a nutshell, there are legal battles to be fought and questions yet unanswered.

With a private cloud, ownership of infrastructure, data, and applications are clarified. The only parties in any legal equation are you and the government that wants access to your data. You don’t have to worry about the third party running the public cloud and how they impact you. There is absolute clarity of ownership.

The Takeaway

The real question to ask is: how much control do you need? If you want a greater degree of customization, clarified data ownership, and your own IT staff also providing security, you want a private cloud. If these things are less important or you have immediate need for scale, go with a public cloud.

Thursday, August 8, 2013

« Back