This is an on-demand service to the cloud infrastructure, which includes servers, storage and networking resources needed by customers to run their operations. The customers can provision, configure, and use this in the same way they use on-premises infrastructure. However, the difference is that the cloud service provider owns and maintains these resources in its own data centers, and customers pay and connect to them via an internet connection. The payment is often subscription-based or pay-as-you-go basis. The customers can choose between virtual machines hosted on a physical hardware or bare metal servers on dedicated physical hardware.
The benefit of IaaS compared to traditional IT is that it gives customers flexibility. The capacity can be scaled up or down based on traffic or need. IaaS allows customers to avoid the upfront expense and overhead of maintaining a data center. It also rids the trade-off between a waste of excess capacity purchase to accommodate traffic and outages due to a lack of adequate capacity.
Platform-as-a-service (PaaS) offers a cloud-based platform for developing, running and managing applications. The provider hosts, manages and maintains all hardware and software included in the platform. This includes servers, operating systems, software, storage, middleware, frameworks, networking, development tools and services.
Users access the PaaS via a graphical user interface (GUI) where DevOps teams can collaborate on their work, such as coding, testing, integration, delivery, deployment and feedback across the application lifecycle.
The key benefit of PaaS is that it enables customers to build, test, update and deploy a wide range of applications faster and at a lower cost. Other critical benefits of using PaaS include faster time to market, low to no risk testing and new technology adoption, simplified collaboration, scalable approach and reduced management need.
Some use cases of PaaS include API development and management, the internet of things, agile software development and the DevOps toolchain. It offers in-built automation that supports continuous integration and continuous delivery.
Software-as-a-Service (SaaS) is a cloud-hosted ready-to-use service/application software. This service enables users to pay a monthly or annual fee to use an application from their web browser, desktop client or mobile applications. The application and the necessary infrastructure for delivering services, such as servers, storage, networking, middleware, and application software, are all managed by a cloud or SaaS vendor. Furthermore, this vendor is responsible for upgrading and dispatching the software, usually invisibly to the customers. The vendor is responsible for ensuring availability and security as part of the service level agreement with the customer. On the other hand, the latter can add more users and data on demand by simply adding the cost of the service.
The benefits of using SaaS include reduced cost due to the management of infrastructure by the service provider, vendor handling everything such as maintaining server hardware and software and managing user access and security. The provider is also responsible for managing storage, maintaining data, patches and upgrading the system. The good thing with this approach is that it has minimal risk, users can be productive anytime and from anywhere, and it is highly scalable. This has driven its adoption by modern businesses that want to do all they can to reduce the cost of operations.