What is a Public Cloud?

By 2020, 83% of enterprise workloads will be in the cloud, about half of which will run in a public cloud. As a result, it’s more important than ever to understand the trade-offs of different cloud strategies, including the qualifications of what is a public cloud vs. a private cloud — and whether a singular or hybrid cloud strategy will best fulfill your business’ objectives.

First and Foremost, What is a Public Cloud?

At its most basic level, a public cloud is a collection of computing resources that are accessible via internet access, usually for a consumption-based usage fee. These public clouds are made up of physical and virtualized hardware and software that can be rented and utilized on-demand by developers and businesses, making it easier to spin up ad hoc applications and environments as demand ebbs and flows. Importantly, the hardware resources are not often nearby, but are instead located in centralized server farms located in dispersed regions around the world. Dominant vendors in the public cloud space include Amazon Web Services, Microsoft Azure, and Google Cloud.

Before the cloud, a business would have to purchase hardware and install software to manage their data in a secure space. This afforded companies with on-premises (or, to some degree, remotely located) data centers a large degree of control over their data and applications. But, with that control came significant management overhead. Your company was also wholly responsible for the security of the physical and virtual resources.

Now that public cloud resources are easily accessible, a business can access those same services and data through a public cloud, balancing performance needs and cost. The most commonly cited reasons for the shift to the cloud are higher availability and scalability.

Additionally, unlike legacy data centers, public clouds can support multi-tenancy. This means multiple entities (companies, individuals) can access and be part of the same cloud space without additional dedicated hardware, so you can essentially distribute responsibility and management of your resources to a wider pool of users.

Benefits of the Public Cloud

Balancing Performance and Cost

Public cloud vendors benefit from their massive scale, which is often passed down to the customer as cost savings. It also saves businesses the expense of hosting a local server and finding talent to manage it. This usually results in less expensive and faster-to-implement projects. However, not all data needs to be stored in high-performance file storage.


Rather than purchasing large amounts of hardware upfront, public cloud services allow you to access the resources you need now and purchase additional capacity as you grow. It also allows organizations to prepare for and meet one-time anomalous usage spikes without a long-term commitment.


Data protection is key to public clouds’ value proposition. Partnering with a large, properly vetted service like Amazon or Google can add a layer of security and remove some of the burden from your internal resources. That’s not to say your team should wholly pass off security responsibilities to an outside form; it’s more of a relief than a replacement.

Many vendors actively invest in security on an ongoing basis. In 2015 alone, Google paid out more than $2 million to people who were able to find vulnerabilities or bugs in their services, that doesn’t include all of the other expenses for their leading security and encryption.

However, security remains an area of concern for many considering the public cloud. Much of the complexity on this topic comes from overblown concerns caused by sensationalized headlines. In reality, there is a balance between the convenience of public cloud and the security problems it may introduce, which has led many companies to actively pursue hybrid cloud strategies.

Public Cloud Pros and Cons

Pros Cons
Public Cloud
  • Ease of scalability —  the cost of infrastructure and hardware is not directly your responsibility
  • Pay-as-you-go, only need to pay for what you need
  • Also very reliable due to multiple data centers
  • Multi-tenancy
  • Limited to the customization of the cloud organization
  • Limited influence over physical hardware
  • Security and backup managed by a third party that may have different security standards or privacy regulations
  • Subject to latency issues associated with usage across the cloud
Private Cloud
  • Higher level of security
  • Greater control of server
  • Multi-tenancy
  • Much higher initial costs (hardware, infrastructure, space, etc.)

Find out more about the unique advantages of private clouds in our related article: “What is a Private Cloud?”