What’s the Diff: Private Cloud vs Public Cloud

Anyone just starting out with the cloud is going to need answers to some basic questions.

The first, of course, is what exactly is the cloud? Put simply, the cloud is a collection of purpose built servers. These servers could perform one or more services (storage, compute, database, email, web, etc.) and could exist anywhere as long as they’re accessible to whomever needs to use them.

The next important question to ask is whether the servers are in a private cloud or a public cloud. This distinction is often tied to where the servers are located, but more precisely, it reflects who uses the servers and how they use them.

What is Private Cloud?

If the servers are owned by and dedicated to only one tenant (user) or group of related tenants, they are in a private cloud. The private cloud is typically on-site (or on-prem or on-premises in IT lingo), but it could be off-site, as well. The owner is responsible for the management and maintenance of the servers and for planning for future capacity and performance to meet the needs of its users. This planning usually involves long lead times to add additional hardware and services (electricity, broadband, cooling, etc.) to meet the future demand.

What is Public Cloud?

In a public cloud, the servers are shared between multiple unrelated tenants (users). A public cloud is off-site (or off-prem or off-premises). Public clouds are typically owned by a vendor who sells access to servers that are co-located with many servers providing services to many users. Users contract with the vendor for the services they need. The user isn’t responsible for capital expenses, data is backed up regularly, and customers only have to pay for the resources they use. If their needs change, they can add or remove capacity very quickly and easily by requesting changes from the vendor who reserves additional resources to meet demand from its clients.

Differences: Private Cloud vs Public Cloud

Private Cloud	Public Cloud
Single client	Multiple clients
On-premises or off-premises	Off-premises
Capital cost to set up and maintain	No capital cost
High IT overhead	Low IT overhead
Fully customizable	Limited customizations
Fully private network	Shared network
Possible under utilization	Scalable with demand

Which Cloud is Right For You?

If you’re a big company or organization with special computing needs, you know whether you need to keep your data in a private data center. For businesses in certain industries, for example, government or medical, the decision to host in a private or public cloud will be determined by regulation. These requirements could mandate the use of a private cloud, but there are more and more specialized off-premises clouds with the necessary security and management to support regulated industries.

The public cloud is the cloud of choice for those whose needs don’t yet include building a dedicated data center, or who like the flexibility, scalability, and cost of public cloud offerings. If the organization has a global reach, it also provides an easy way to connect with customers in diverse locations with minimal effort.

The growing number of vendors and variety of public cloud services indicate that the trend is definitely in favor of using the public cloud when possible. Even big customers are increasingly using the public cloud due to its undeniable advantages in rapid scaling, flexibility, and cost savings.

Enter Multi Cloud and Hybrid Cloud

For some, a combination of clouds could provide the best solution. Using multiple public cloud vendors (multi cloud) for independent tasks and duties can provide redundancy and cost savings. The data centers and infrastructure can be spread out geographically to decrease the risk of service loss or disaster, and it makes sense financially to store the second or third copy of data with an additional vendor that offers a good and reliable service at a lower cost.