The term cloud services is a broad category that encompasses the myriad IT resources provided over the internet. Most cloud computing services fall into three broad categories: infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (Saas).
The management responsibility for the company starts with the operating system layer and the provider ensures the availability and reliability of the infrastructure provided.
With IaaS, you rent IT infrastructure—servers and virtual machines (VMs), storage, networks, operating systems—from a cloud provider on a pay-as-you-go basis. IaaS is the most flexible cloud computing model and clients have true control over their infrastructure.
Platform as a service (PaaS)
Platform-as-a-service (PaaS) refers to cloud computing services that supply an on-demand environment for developing, testing, delivering and managing software applications. PaaS is designed to make it easier for developers to quickly create web or mobile apps, without worrying about setting up or managing the underlying infrastructure of servers, storage, network and databases needed for development.
PaaS provides a very simple way to test and prototype new applications. It can save money when developing new services and applications. Applications can be released more quickly than usual to get user feedback. The API economy is the new paradigm in development, and the cloud provides the perfect platform for its implementation.
Software as a service (SaaS)
Today, SaaS patterns are generally accepted by many companies that want to benefit from application usage without the need to maintain and update infrastructure and components. Mail, ERP, collaboration, and office apps are the most accepted SaaS solutions. The flexibility and elasticity of the SaaS model are great benefits. Software-as-a-service (SaaS) is a method for delivering software applications over the Internet, on demand and typically on a subscription basis. With SaaS, cloud providers host and manage the software application and underlying infrastructure and handle any maintenance, like software upgrades and security patching. SaaS applications are usually provided on a subscription model. Users connect to the application over the Internet, usually with a web browser on their phone, tablet or PC.