What is a Public Cloud Deployment Model?

Public cloud, also known as external cloud, is a form of cloud computing that involves a third party providing end customers with access to the computing resources they require, such as servers, applications, and storage space, through the Internet. The provider runs them from its own data centers; the AWS Cloud, for example, spans 39 geographic regions as of October 2026. Public cloud services are usually billed on a ‘pay-as-you-go’ basis.

The main cloud deployment models are the public cloud, private cloud, and hybrid cloud. Every model is geared towards the needs and demands of a certain group of users. The public cloud offers shared resources for cost efficiency, the private cloud provides dedicated resources for enhanced control, and the hybrid cloud combines both for flexibility. The ideal model for your organization depends on specific requirements like security, budget, and desired level of control.

Public cloud differs from on-premises infrastructure by ownership, payment structure, flexibility, assistance, and openness. Above all, while public cloud resources are owned and run by the third-party CSP, on-premise resources are owned and run by the actual company. This results in variations in costs, scalability, and responsibilities.

In this multi-tenancy model, each customer’s data and applications remain isolated (Microsoft Azure). However, in public cloud environments, data is stored across multiple servers in data centers owned and managed by cloud service providers (CSPs), where users lack direct control over these servers and have less control over the underlying infrastructure compared to on-premises solutions.

When considering cloud deployment models, the public cloud is applicable for scenarios involving fluctuating demand, such as websites with variable traffic, development and testing setups, and offsite data storage.

Some of the leading public cloud solutions include AWS, Azure, and GCP. The AWS Cloud spans 39 geographic regions as of October 2026 (AWS). Public cloud services fall into three models:

• Infrastructure as a Service (IaaS): Virtual machines, storage, as well as networking.
• Platform as a Service (PaaS): Cloud-based solutions for application development and deployment.
• Software as a Service (SaaS): Applications stored in the cloud (such as Salesforce, Dropbox, and others).

Visit AWS, Azure, and GCP websites to look for more information on the options tailored to your organization’s needs.