AS400 Application Guide — The History, Evolution, Benefits, and More


Are you shying away from the AS400 iSeries?

Have you heard the rumors that AS400 software is outdated and incompatible to meet modern-day business needs?

Are you hesitant about integrating IBM AS400 iSeries into your existing business infrastructure?

Are you an IBM i user, curious about its present and future?

Join us as we answer each of these questions in detail to help you make informed decisions about the iSeries AS400 Solutions & Services for your business.

Let’s unravel.

About AS400

The AS400 is a server by IBM that is counted on by multiple organizations in a broad range of industries. With an unparalleled legacy reputation of 3 decades, AS400 System remains at the top of powerful server platforms.

It is evolving with the changing business needs while enhancing its simplicity, power, and reliability. With proven support, it is still running critical business operations in varied industries around the world.

The Evolution Of AS/400 To IBM i

AS400 is a computer system introduced in 1988 and has the highest market share of 36.03% today — states a report by Enlyft.

Remarkable, right?

Let’s see the evolution of the old AS400 to the legendary IBM i today.

IBM introduced the first computer system in 1988. It was comprised of the operating system called the Operating System/400 (OS/400) and the hardware- Application System/400 (AS/400). Its first product had an integrated database and other important functions. With changing business needs, both the OS400 and AS400 have evolved significantly.

But that’s not how it was formed.

It first began in 1978 when IBM designed a computer using the object-based operating system, System/38, similar to the modern database — Db2. The system was designed to run the AS400 software system smoothly.

Later, in 1983, IBM designed another computer system called System/36 which was only a file management machine. It used RPGII as the programming language.

Fast forward to 2000, IBM rebranded the AS400 into an eServer iSeries and had the OS400. It became a popular server for running online businesses.

In 2006, the company introduced the iSystem server featuring the i5/OS operating system. It gained popularity among businesses that could not run the Windows OS.

Moving on to 2008, IBM introduced a powerful combination of i5/OS (Present day IBM i) and the Unix OS (AIX). Power Systems or IBM Power

have a built-in database called DBMS, DB2/400.

Despite years of upgrades and rebranding, IBM continued to focus on compatibility.

Thus, users can easily run AS/400 programs in Modern Power Systems without a problem. Companies globally continue to hope that the IBM upgrades i series every few years with current-day functionalities.

Now that you know the evolution of AS/400 TO IBM i, let’s understand the AS400 and IBM Series.

Understanding AS400 and IBM Series:


The AS400 i series and IBM iSeries are both computer systems developed by IBM, renowned for their dependability, stability, easy-to-use ability, and performance.

What is IBM iSeries?

IBM i is an operating system backed by IBM systems, says Techopedia.

It is an EBCDIC-based operating system designed to run on IBM Power Systems & IBM PureSystems. Although it is under process, a considerable number of businesses are using it for stability and integrity when it comes to application support.

IBM iSeries is renowned for its versatility and robustness in handling high workloads in businesses. It provides a complete set of integrated software components that enable businesses to manage databases and handle networking tasks seamlessly.

In addition, the IBM iSeries is renowned for its scalability, helping businesses grow their computing resources as their needs grow.

What is AS400?

The AS400 is a midrange computer system combining hardware, operating system, database, and development tools into one package.

It was designed by IBM to serve the needs of businesses in need of reliable and efficient computing solutions.

What makes AS400 unique is its iconic single-level storage architecture. Traditionally, the data and instructions are stored in separate address spaces. But with the AS400, data, and programs can be accessed from the same address space which improves performance, simplifies programming, and boosts stability.

Overall, the AS400 and IBM iSeries are renowned as dependable and time-tested systems that continue to be at the vanguard of many businesses across different industries.

How Does AS400 iSeries Benefit You?

AS400 can be highly beneficial for your business.

Let’s discuss its benefits.

· Reliability and Stability

One of the best features of AS400 IBM is its reliability and stability. It can be a perfect choice if your business operation involves critical applications.

Businesses trust the platform to run their essential operations without worrying about downtime and system failure.

· Security Features

Do you deal with critical data and information that needs security from hackers and cyber threats?

If yes, the IBM iSeries is a suitable choice for you.

It has a robust architecture, with incredible features like object-level security, role-based access control, and integrated encryption. It offers security against growing cyber threats, for your discreet business applications.

· Scalability

Another renowned feature of the IBM iSeries AS400 is its scalability. It allows businesses to adjust their computing resources as per their demand. From handling increased data volume to housing additional users, the iSeries IBM fulfils the growing needs of your business without blowing your budget.

· Modern Application Integration Capabilities

IBM regularly updates the system with modern technologies like web services, cloud computing, and mobile applications. Businesses are hopeful of regular technological advancements which they can leverage to retain the stability and reliability that the AS400 iSeries is known for.

· Cost-Effectiveness

Along with the amazing features, the AS400 i Series is also cost-effective. In comparison to the large mainframe systems, it provides a balance of performance and affordability making it a preferable option for businesses looking for a one-stop computing solution without crossing the budget.

Are you thinking of modernizing your legacy system?

AS/400 modernization services 

AS/400 modernization services offer a custom-made solution designed to meet your business needs. It helps you make the most of your IBM i investment and offer a smooth integration, improved user experience, and enhanced scalability.

Get rid of the old legacy system and embrace the modern iSeries Integration.

FAQs: Answering Common Questions About AS400 and IBM iSeries:

1. Is the IBMi-series outdated and no longer relevant in today’s technology landscape?

Although IBM i is old, it is one of the systems that has surprised the business world with a rich legacy while constantly evolving to meet the growing needs of the business.

Instead of going irrelevant, it has gained popularity among modern developers who are realizing its importance owing to its reliability, scalability, security, and affordability.

Interestingly, Information Technology and Services and Computer Software are the 2 largest industries with 18% stake and the latter with 8% stake as the largest segments using AS400, as per Enlyft.

The same report mentions that the USA, followed by the United Kingdom and Canada has the highest number of companies using IBM i.

Are these companies planning to leave AS400 behind? On the contrary, the majority of enterprises continue to have 75–100% of their workload on the AS400 software, reveals a survey conducted by IBM.

The statistics clearly echo that AS400 is not dead instead, it is highly relevant in the modern business landscape.

2. Is AS400/iSeries limited to traditional green-screen applications?

Initially IBM i supported only green-screen applications. But the scenario has changed. IBM later introduced a new “Graphical User Interface” (GUI) for IBM iSeries and Power Systems.

This GUI provided a user-friendly and attractive interface compared to the typical green screens. Developers started using GUI-based applications, and customers found them easier to use. Ever since, customers prefer GUIs over green screen UIs.

3. Is AS400 System only suitable for large enterprises?

IBM is suitable for all sizes of businesses, whether small, medium, or big. Let us prove — Out of all customers that are using IBM i, 22% consist of small organizations, 41% comprise medium-sized, and over 38% of large businesses, as per Enlyft.

Proving that the AS400 system is a smart choice for all-size of organizations.

4. Is the AS400 iSeries challenging to integrate with other systems?

The As400 system was originally designed as a standalone solution without much focus on the integration feature. However, fast-forward to today, businesses can integrate modern-day tools easily with the IBM i owing to the availability of specialized integration connectors, APIs, and advanced integration platforms that has made it manageable.

The qualified team of AS400 i Series developers offers a seamless AS400 iSeries Development required for your business.

5. Does AS400 lack modern features and innovations?

Modern IBM i is highly designed for modern businesses.

It offers:

· Robust security

· Smooth integration

· Open-source software

· Modern user interface

· Web Services and APIs

· Modern programming languages such as Java, PHP, Python, and Node.Js

6. Is IBM AS400 suitable only for specific industries?

The answer is No! The AS400 series is suitable for multiple industries, including healthcare & hospital, information technology, banking, financial services, computer software, retail, insurance, etc.

IBM i is mostly used by Information Technology and computer software industry, as per a report by Enlyft.

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