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The public cloud computing model enables users to access a wide range of resources, from applications and virtual machines to development platforms and enterprise infrastructure, over the public internet. Modern public cloud solutions provide resources through a combination of environments that offer greater performance and security, highly available applications, infrastructure, services, and keep costs down.

Public cloud resources are typically available on a pay-per-usage basis. Other services may be free to access or sold on a subscription-based model. Common public cloud examples include services like Amazon Web Services, Gmail, Google Drive, and Hotmail.

How do public clouds work?

Public clouds work by virtualizing resources into shared pools that can be accessed by customers. A public cloud provider hosts IT resources in scalable, on-demand pools that customers can access via the internet or dedicated networks. It supplies the IT infrastructure required to host and deploy resources in the cloud, alongside services and tools that help businesses manage their cloud applications, such as data storage, monitoring, and security.

There are three types of public cloud service delivery models:

  1. Infrastructure-as-a-Service (IaaS):  IaaS is the most hands-on cloud model that organizations can select and helps to control and maintain their resources. Iaas delivers solutions like data storage, networking, servers, and virtualization to customers. Customers can access as much data storage or computing power as they need, but they have to run it on their own software platform.
  2. Platform-as-a-Service (PaaS):  PaaS involves cloud providers delivering an entire cloud infrastructure and software platform to customers. The data, networks, servers, and virtualization of infrastructure are provided through a platform comprised of operating systems, runtime, and middleware. This approach removes the complexity and cost of building and maintaining an on-premises IT infrastructure
  3. Software-as-a-Service (SaaS):  SaaS involves providers delivering and maintaining applications and the cloud infrastructure that supports them through web portals. SaaS is the most popular public cloud solution as it removes the hard work of managing and running applications and ensures that organizations don’t have to store application data on local hard disks.

What's the difference between public cloud and private cloud?

The critical private cloud vs public cloud difference is that public cloud resources are hosted by a third-party provider while private cloud resources are hosted internally by an organization. 

A private cloud model requires an organization to invest in the equipment and hardware necessary to build and maintain its IT infrastructure. A common risk with this approach is that if usage reduces, the organization is lumbered with costly resources and unused or underutilized hardware. However, the private cloud model is typically used by organizations that need to store highly sensitive data or meet federal and state regulations around data control.

What's the difference between public cloud and hybrid cloud?

The difference between public-private-hybrid cloud options is that hybrid combines the use of public cloud services and private cloud. A hybrid cloud enables organizations to reap the benefit of both models and choose between the two depending on their specific requirements. For example, a hybrid approach gives an organization the option to store their most sensitive data in a private cloud while moving other information into the public cloud.

Benefits of public cloud

The most significant public cloud benefits include being elastic and scalable, which is ideal for organizations that need to be flexible to changing workload demands. The public cloud model is also highly efficient as it enables customers to only pay for the resources they actually use and, equally importantly, not pay for the resources they don’t use. Further cost-effective benefits include removing the need to purchase IT infrastructure and hardware.

Additional benefits of public cloud services include:

  • New technology access: Using the public cloud gives organizations access to new technologies and software advances as soon as they become available. Operating a private cloud could make these new services too expensive to gain access immediately. 
  • Unlimited scalability levels: The public cloud enables organizations to expand and reduce their cloud capacity and resources to meet spikes in traffic and shifts in user demands. 
  • Greater flexibility: The scalable nature of the public cloud enables organizations the flexibility to store and access vast volumes of data. This is ideal for backing up applications and data to prepare for unseen events like emergencies or outages. 
  • Higher availability and redundancy: Organizations can gain higher availability and greater redundancy based on their provider’s cloud locations. They can also ensure end-users get faster connectivity to cloud services through their provider’s network interfaces.

Cloud solutions for the world’s most demanding organizations

Unisys cloud solutions adhere to the highest security and compliance standards to mitigate risk at each stage of the cloud adoption lifecycle. We design, deploy, and manage flexible and customized cloud solutions that effectively address our clients’ current needs while establishing a foundation to support long-term growth and change.

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