Private Cloud vs. Public Cloud: What's the Difference?

The overall benefits of cloud computing are clear. It provides scalability, instant provisioning, virtualized resources, and the ability to quickly expand your server base. But what is the best method—private cloud or public cloud? This blog will help clear the cloud of confusion, so you can make the best decision for your company.

What is a Private Cloud?

To the skeptic, private cloud looks a lot like what we used to call an on-premise data center. However private clouds use virtualization, software (e.g. JD Edwards, SAP) and automation to organize infrastructure. This gives them some of the flexibility found in the public cloud without sacrificing control over security and data privacy.

Private cloud hosting is a single-tenant environment where the hardware, storage and network are dedicated to a single client or company. Unlike public clouds, private clouds are typically maintained, provisioned and managed by their users, not third-party IT staff. This includes setting up a firewall. Whether running software on a public-facing server or using actual hardware, the firewall prevents anyone from accessing resources without proper credentials (e.g. user ID, passcode, special key number).

Many mid- to large-sized organizations choose private cloud for benefits including:

• Increased security — Lowering the risk of access by non-users via the Internet or in the same data center
• Compliance — Meeting Sarbanes Oxley, PCI and HIPAA standards
• Customization — Offering the ability to specify hardware, network, and storage performance
• Hybrid deployment — Integrating dedicated servers to run high-speed database applications. This can’t be achieved solely in a public cloud.

Fully-managed private clouds are not typically delivered through a utility model because the hardware is dedicated. However, a virtual private cloud provider will offer pay-as-you-go with the bonus of specifically provisioned hardware, network and storage configurations.

What is a Public Cloud?

When most people hear the word “cloud” it’s public clouds they think of. Public clouds started out as applications hosted over the internet or Software as a Service (SaaS). Today’s public clouds include applications, infrastructure, and even data storage. They are provisioned, maintained, and managed by a third-party vendor who assumes responsibility for the entire cloud infrastructure and all the customers accessing it.

Public cloud is a multi-tenant environment, meaning you typically buy a “server slice” in a cloud computing environment that is shared by other clients. For this reason, it is most often used for web servers or development systems with less rigorous security and compliance requirements.

Public clouds, such as Amazon EC2 and Microsoft Azure, have many benefits including:

• Flexible pricing — Allowing users to pay by the hour for only the compute resources used
• No contracts — Letting users spin up and shut down servers as needed
• Self-management — Giving technical buyers the ability to setup and manage server details

Cloud computing continues to impact how IT resources are delivered. Understanding the advantages and limitations of private cloud and public cloud can help you make the best decision for your company’s future.