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What is Public Cloud?

What is Public Cloud

What is Public Cloud?

Public cloud helps businesses across the world unlock the power of cloud computing. It’s a model that offers limitless computing resources to the general public – from anywhere with an internet connection.

The public cloud can be used alone, in a multi-cloud setup, or combined with a private cloud resource in a hybrid cloud solution. Businesses who adopt public cloud can increase flexibility, reduce maintenance time, and save on IT costs.

In this blog, we’ll learn what the public cloud is, who are the major providers, and how your business can benefit from moving to the cloud.

Definition of Public Cloud Services

Public cloud services use their cloud computing infrastructure to offer various resources over the internet. Almost anybody can use these resources, making the public cloud one of the most flexible and accessible cloud options available.

A business using the public cloud can choose from many workloads and resources – from fully-fledged software to cloud storage, servers, and virtual machines. To add to their flexibility, these cloud technologies are usually billed on a pay-as-you-go basis.

As such, public cloud infrastructure gives companies extensive options. Choose one platform for its scalability, another for its high speeds, and others for storage space. With the public cloud, users are free to choose the service that fits their needs.

How Public Cloud Works

Public cloud vendors – through their vast buying power and expertise – host huge numbers of computing resources in data centres. These data centres provide perfect conditions for the equipment, giving them high performance and longevity.

Public cloud providers offer these resources for public use. Users can select their public cloud resources, provision them on private or multi-tenant infrastructure, and get to work.

Provisioning public cloud resources is much more cost-effective and straightforward than installing on-premise IT infrastructure. Users connect to the internet, log in, and begin to use their on-demand resource. If needs change, users can upgrade or downgrade their service as required.

What are the service models of public cloud computing?

There are three primary service models of public cloud computing.

Software as a Service (SaaS)

The first is Software as a Service (SaaS). SaaS is the most comprehensive cloud computing model, hosting ready-to-use software on cloud infrastructure. With this, users can connect from anywhere with an internet connection and begin to use the software. SaaS options are more typically used for collaboration, messaging, and work, providing a highly flexible and cost-effective choice.

Platform as a Service (PaaS)

Platform as a Service providers give users the tools needed to build new apps in the cloud. With PaaS cloud resources, developers can get to work designing, building, and testing – instead of having to manage and maintain their high-performance infrastructure.

Infrastructure as a Service (IaaS)

Infrastructure as a Service provides users with the hardware and computing services needed to design their cloud IT infrastructure. In typical IaaS environments, you’ll find everything from data storage to compute resources available on-demand.

Public Cloud Service Providers

While there are various public cloud vendors, the market is led by a few major third-party providers.

Amazon Web Services (AWS)

Amazon’s cloud computing services have grown to become a market leader. In Q1 of 2022, it increased its market share as the largest public cloud provider – responsible for around 33 per cent of the market.

Amazon Web Services (AWS) gives users flexible access to various infrastructure and platform resources. Its huge economies of scale mean that Amazon can offer cutting-edge technology at competitive, pay-as-you-go prices. This gives users access to resources that might not otherwise be available – all backed by AWS public cloud knowledge, expertise, and a massive choice of resources.

Microsoft Azure

The second largest public cloud provider is Microsoft. A giant of the operating system world, Microsoft is also a major player in the cloud space, with a market share of around 20 per cent.

Microsoft Azure public cloud offers users a huge range of options to create their perfect cloud platform. Much like AWS, Azure’s available tools include storage, compute, analytics, and networking resources. It also enjoys enormous buying power, offering its advanced resources over the internet on a flexible billing basis.

Google Cloud Platform

Joining Amazon and Microsoft in the top three public cloud providers list is Google. Its offering – Google Cloud Platform (GCP) – is slightly less popular than the first two, making up nine per cent of the market.

GCP offers several platforms for hosting resources, managing data, and developing apps. The main benefit of choosing one of the big three providers is access to their leading technologies, flexible pricing, and expertise.

Public Cloud vs Private Cloud

To give the public cloud context, it’s important to explain the private cloud. The private cloud is cloud computing resources dedicated to – or owned by – one organisation. They will have full usage of the resource, unlike the multi-tenant public cloud.

Many companies choose to employ a private cloud resource over a public resource due to data privacy, legislation, or personal security preference. The two can be combined to create best-in-breed IT systems.

Public Cloud and Hybrid Cloud

A hybrid cloud model uses a public cloud infrastructure with a private cloud resource. Many cloud-native companies employ a hybrid cloud to pair the flexibility of the public cloud with the security and control of the private cloud. By using the two types of cloud services, companies can choose exactly which one fits each task within their business.

Public Cloud and Multi-Cloud

Likewise, a company might choose to use a multi-cloud deployment. Multi-cloud, in this context, simply means two or more public cloud services. This lets organisations pick and choose providers – perhaps preferring one for data storage, another for computing, and a third for software. Overall, multi-cloud environments keep a business agile while selecting the best provider for each job.

What are the Benefits and Challenges of Public Cloud?



Public cloud services can grow with your business. You might need more cloud storage, or to provision an entirely new resource. With the public cloud’s self-service model, adding or changing resources is generally straightforward.

You can also use the power of automation. Many workloads let you automate scaling – adding resources during busy times and downsizing when they’re not needed. This elastic approach can be a great option for seasonal or more reactive companies.


Cloud computing can also bring cost savings in many forms. For one, there is a much lower initial cost than if you were to purchase IT equipment outright. This is especially true if you are looking to deploy high-performance computing for machine learning, low-latency computing, high bandwidths, or AI automation.

There is also an expertise cost involved in on-premises computing. Not only would you need skilled workers for the initial install, but also for ongoing maintenance, patching, and downtime. With the public cloud, you leave the skilled and time-consuming work to your provider.


One of the public cloud’s most significant benefits is the peace of mind it brings. Resiliency means different things to different businesses – but avoiding downtime is usually near the top of the list.

With the public cloud, you have the reassurance that services suffering from downtime can be switched to another. Larger workloads can be spread across multiple servers – even multiple locations. With business continuity so critical, many public cloud service providers give uptime assurances baked into service level agreements.

Flexible Pricing Models

Your cloud strategy usually comes with flexible pricing models. You’ll know exactly how much a resource costs before deploying it, and you only pay for the time and power you use.

Many cloud platforms will also give you monitoring power over your spending. Not only can they help you budget, but also react to changes in usage and cap any overspending.

Disaster Recovery Options

Public cloud data storage offers companies an excellent disaster recovery option. With its multiple locations, resources and storage types, companies can tailor their backups to cover all bases. This added redundancy and resiliency can help companies overcome worst-case scenarios – including natural disaster, disk failure or cyber-attacks.


While public cloud computing offers many benefits, it can also bring challenges.

Public Cloud Security

Some companies have security concerns with the public cloud. While it is safe –much of the security technology is probably more advanced than businesses would purchase themselves –there is no direct control over infrastructure. This is usually not an issue, but many companies might prefer the reassurance of managing private cloud infrastructure.


The public cloud, due to its flexibility and myriad options, can potentially lead to confusing management for users. This might be down to using multiple different pricing models, or a lack of synchronisation between services.

Multiple public cloud services can also make maintaining data quality a challenge. Without APIs or proper controls, it’s quite simple for data to become outdated or incorrect. There is also the risk of shadow IT – where users employ new or different cloud services without consulting the IT department.


The public cloud may not be an ideal option for companies dealing with strict legislation. This is especially true when handling sensitive data, or data subject to geographical restrictions. In this case, it’s usually best to employ a hybrid cloud model.

Public Cloud Migration

Migrating to the public cloud, in some cases, can be very challenging. While cloud deployment is typically straightforward, it does have hurdles:

  • is your data ready to be moved to the cloud?
  • will you have to build new software?
  • does your IT team have expertise in the cloud platform of choice?

Depending on the answers to these questions, it might be better to employ a hybrid model.

Why choose Public Cloud?

So, why and when would you choose the public cloud? It’s a great fit for companies that want:

  • to guarantee uptime and have a manageable plan in place for disaster recovery
  • to mix and match which provider they use for each task – avoiding vendor lock-in
  • to move a legacy system into the cloud, providing employees and customers with easier access
  • to save money on IT equipment and maintenance
  • to use the latest technology for resource-heavy workloads

The public cloud might not be the best fit for companies that want:

  • dedicated use of computing resources
  • compliance with data legislation, or holding sensitive data
  • advanced or bespoke data centre technology to run large workloads
  • to invest heavily in IT infrastructure

These pros and cons often mean that companies employ a hybrid strategy – using the public cloud for less complicated or critical workloads, combined with a private cloud environment for more control.


The public cloud is a model of computing offering many different resources over the internet. Users can deploy simple, advanced, or specialist workloads to fit different needs – while paying only for what they use. To discover how your business can unlock the power of the cloud, speak to a specialist today.