Hello! We are a writer team from Definer Inc. In this issue, you are wondering about the difference between SaaS, PaaS, and IaaS. Let's take a look at the actual screens and resources to explain in detail.

The difference between SaaS, PaaS, and IaaS is the difference in areas of responsibility between the cloud provider and the user. The following diagram explains the difference.   SaaS (Software as a Service) In SaaS, the provider (cloud service provider) is responsible for everything from hardware to OS, middleware, and applications. Since the application part is also the provider's responsibility (since it is created by the provider), the user does not develop the application, but only uses the application provided by the provider. SaaS is a service that allows users to easily use various services created by providers without having to develop their own software.   PaaS (Platform as a Service) In PaaS, the provider (cloud service provider) is responsible for the hardware, OS, and middleware, while the user is responsible for the application. In other words, users build their own applications on the platform provided by the provider. PaaS is a development platform that allows users to implement services as long as they are programmed.   IaaS (Infrastructure as a Service) In IaaS, the provider (cloud service provider) is responsible for the hardware, while the user is responsible for the OS, middleware, and applications. The user uses the infrastructure resources (servers, networks, etc.) provided by the provider, configures the OS, installs middleware, and implements applications for the IaaS. IaaS requires the user to manage the OS and middleware in addition to developing the application, but it allows for more customizable development because users can use any middleware they wish.   (Supplemental) On-premise When creating on-premise systems, the user is responsible for all hardware, OS, middleware, and applications. Since everything is owned by the company, highly customizable applications can be created, but there are disadvantages such as initial costs.

SaaS is software that requires no development and is available over the Internet. Use cases are used to solve specific issues for companies or individuals. For example, SaaS is emerging in a variety of areas, such as communication, including meetings and chats, and recruitment and labor management. Famous services are too numerous to mention, but some examples include Money Forward and SanSan.   (Reference) Image of SaaS services (Reference：https://www.atlassian.com/ja/software/confluence)     In the SaaS market, tech companies, primarily from the United States, are on the rise. The SaaS industry rankings for 2021 show companies such as Microsoft, Oracle, SAP, and Salesforce at the top of the list. In addition, the market size is said to be in the hundreds of billions of dollars, although it varies according to various reports.

PaaS is a development platform that requires only an application and no database, server, or operating system. Use cases include the development of applications that do not have many functions or requirements, or applications that are not highly customizable. Famous services include Cybozu's Kintone and Salesforce's Heroku.   (Reference) PaaS service image (Reference：https://kintone.cybozu.co.jp/support/newdesign.html)  

IaaS is a service that enables the use of IT infrastructure resources such as servers and networks required for development over the Internet. Servers and other resources that previously had to be purchased in-house can now be easily used on the Internet for a pay-as-you-go fee. Use cases include the development of applications and services with many functions and requirements that require customization. Well-known services include AWS EC2, S3, and Azure VM.   (Reference) Image of Iaas services (Reference：https://docs.microsoft.com/ja-jp/troubleshoot/azure/virtual-machines/serial-console-windows）   A 2022 Gartner study showed that the top four companies - AWS, Microsoft Azure, Alibaba, and Google Cloud - account for about 3/4 of the total market. The IaaS market size is also estimated at $90.9 billion.

This article summarizes the contents of this article. 　SaaS is software available over the Internet with no development required. 　PaaS is a development platform that requires only the preparation of an application and does not require a database, server, or operating system. 　IaaS is a service that allows you to use IT infrastructure resources such as servers and networks required for development over the Internet.

✅　Gatner　Gartner Says Worldwide IaaS Public Cloud Services Market Grew 41.4% in 2021 ✅　Atlassian　Confluence ✅　Cybozu　New Kintone Design Concept ✅　Microsoft　Azure Serial Console for Windows ✅　deallab　SaaS Industry Market Share, Revenue Ranking and Market Size Analysis

✅ PrismScaler is a web service that enables multi-cloud infrastructure construction such as AWS, Azure, and GCP in just 3 steps, without requiring development and operation. ✅ It is a solution that streamlines "automatic construction," "automatic monitoring," "problem detection," and "configuration visualization" related to cloud infrastructures, and takes over the tedious and difficult tasks performed by cloud engineers and SRE/DevOps engineers. ✅ It is intended for a wide range of usage scenarios such as cloud infrastructure construction/cloud migration, cloud maintenance and operation, and cost optimization, and can easily realize more than several hundred high-quality general-purpose cloud infrastructures by appropriately combining IaaS and PaaS.  

In "[Introduction to AWS] Gathering Server Information with AWS Application Discovery Service - PrismScaler", useful introductory information is available free of charge. For consultation and inquiries, please contact "Definer, Inc.

　Definer Inc provides one-stop solutions from upstream to downstream IT. 　We are committed to providing integrated support for advanced IT technologies such as AI and cloud IT infrastructure, from consulting to requirements definition / design development / implementation, and maintenance and operation. 　Through DevOps and CI/CD consulting, we realize "creating a mechanism for business growth with fewer engineers," "creating an environment where engineers are happy and easy to hire," and "a fast agile development environment. 　PrismScaler is a high-quality, rapid, "auto-configuration," "auto-monitoring," "problem detection," and "configuration visualization" for multi-cloud/IT infrastructure such as AWS, Azure, and GCP. ©️ Definer Inc. All rights reserved.