What is AS400 Mainframe? IBM AS/400 Mainframe (2023)

AS400 Mainframe is an IBM platform used for commercial purposes since the mid-1980s. It is a type of minicomputer based on the IBM System/38 architecture. The AS/400 mainframe delivers stability, scalability, and security characteristics that make it suitable for running mission-critical applications in medium to large business environments. As400 Mainframe is the superior server of choice when managing large databases and processing bulk data. With unparalleled speed, reliability, scalability, and security provided by its powerful hardware, distributed computing capabilities, and advanced operating system software – mainframes will effortlessly handle even your most demanding requirements!

Before IBM released the object-based OS, they had already developed System/38 in 1978, resembling Db2. Furthermore, some of its concepts contributed to the success of the AS 400 Mainframe software system. In 1983, another computer named System/36 was launched with RPGII as its main programming language, and it primarily served as a file management machine.

AS400 Mainframe
AS/400 Mainframe

How does AS400 Mainframe works?

As400 Mainframe is uniquely engineered to:

  • Leverage the power of common operating systems such as Linux® and specialized ones like IBM z/OS® while taking full advantage of unique hardware capabilities through software.
  • With capacity available on demand and shared memory for direct interservice communication, it supports an extraordinary amount of simultaneous transactions and input/output.
  • Ensure the highest levels of safety with integrated cryptographic cards and groundbreaking software. For example, As/400 Mainframe has been known to handle up to one trillion secure web transactions every day while being able to keep data safe through policy management.
  • Bolster your system’s ability to survive by using multiple redundant layers for every element (such as power supplies, cooling tips, backup batteries, CPUs, and I/O components) and stress-testing them in extreme weather conditions.

Who uses AS400 mainframes & why do they use them?

Who utilizes As400 mainframes? Just about everyone! If you have ever used an ATM to access your banking account, then odds are you were utilizing a machine powered by As400 ERP. So the next time you use one of these machines, know that it’s running on this powerful system – and helping makes everything go as smoothly as possible for consumers everywhere.

The Mainframe As400 computer is a cornerstone of efficient operations for most major corporations today. While other computing techniques exist and are used in many businesses, these mainframe computers are especially valuable in the modern e-business domain. Banking, finance, health care, insurance firms, government departments – you name it – all these industries use this technology as their basis to deliver excellent services while setting new standards in efficiency.

These powerful machines can easily handle data processing in large amounts while also offering security and reliability. Businesses today depend more on technology than ever before, and As 400 Mainframe makes it easier to manage their IT infrastructure requirements. It is the perfect solution for many of these businesses as its cost effective, reliable, secure, and easy to use.

Strengths of AS400 Mainframe

As400 Mainframe offers a wide range of features and benefits, including:

Reliability, availability & serviceability

  • Reliability: Thanks to its hardware components that feature automated self-testing and recovery mechanisms, the system enjoys exceptional reliability. Additionally, thorough testing and an ability to rapidly implement fixes for identified issues, further enhance the software’s dependability.
  • Availability: In the event of a breakdown, this system can instantly restore its functionality without disrupting non-affected components. This recovery technique covers hardware – through the utilization of spares for ineffective elements – and software via the operating system’s layers for error management.
  • Serviceability: Our system is adept at pinpointing the source of any technical failure, giving us the control to replace hardware and software components without disrupting other operations. Such flexibility means we can effectively swap out pieces with well-defined replacements – be it in terms of hardware or software.


Data—customer lists, accounting data, staff information—is a company’s most precious asset. This sensitive data must be securely managed and accessible to authorized individuals. The mainframe can protect and share the firm’s data with different users.

A secure computer system restricts users from accessing or changing system objects, including user data, except through authority-controlled interfaces. The AS/400 Mainframe can safeguard many diverse applications that access vital data.


The scalability of hardware, software, or a distributed system is the capability to retain top performance regardless of the increasing number of processors, memory space, and storage. With scalable systems in use for complex jobs with either large-scale or small networks – you can be sure that reliable results will follow!

As a corporation grows in staff, customers and partners – so too do its need for more computing resources. Increasing processors of the same size are confusing to manage; instead, merging smaller ones into larger systems can be much simpler! Due to hardware, software, and operating savings, many companies have reaped the benefits of lower TCO (total cost of ownership) by using AS400 Mainframe systems.

AS 400 Mainframe is renowned for its hardware and software scalability, letting them run multiple copies of the operating system as a single entity known as a simplex.

Continuing compatibility

Maintaining compatibility with new and older applications is a major challenge that the AS400 Mainframe can easily address. The platform provides backward compatibility between versions so that users can smoothly transition data from one generation to another. This makes it easier for companies to upgrade or redesign their systems without worrying about data preservation being lost. Furthermore, its robust log management feature helps IT staff determine the source of any possible errors.

Example of AS/400 Mainframe Computer

Modern businesses depend on the robustness and security of As400 Mainframe Computers for various purposes. These incredibly reliable computing platforms are used in banking, insurance, healthcare, government, and public utilities sectors with great success. With unparalleled compatibility and stability guarantees, their continued use is guaranteed for years.

When accessing the Mainframe As400, the most efficient way is through its core element (SE). This console also serves as a hub for all its components, being physically linked to the main processor and stored within a CPC frame. It acts as the central point of control (CPC) for an As400 Mainframe Computer.

IBM’s hardware management console (HMC) and AS400 operating system on the mainframe are no match for this software. It is connected to the HMC cluster communication system, granting it access from an IP business network with proper configuration — IBM zSeries, System z9, or even its latest version, System z10 As400 Mainframe Computer being common examples of its usage.

AS400 Mainframe Operating System & Capabilities

An AS400 mainframe system acts as the main data repository in a corporation’s data processing center, providing access to users through less powerful devices such as workstations, terminals, and other similar equipment. These advanced technologies feature an array of distinct characteristics and objectives that vary dramatically from each other.

Z is an exceptionally reliable operating system specifically designed for IBM AS 400 mainframe computers, providing a comprehensive suite of programs to manage the components such as memory, processors, and peripherals. Used by many organizations for mission-critical applications, Z offers unprecedented stability and accuracy to ensure operations run smoothly.

IBM brought the Z operating system to life in 2000, providing enhanced security and maintenance for computers. It operates on a 64-bit design and is still in use today with AS400 Mainframe computers, which are renowned for their compatibility and dependability due to expert planning and implementation.


What are examples of the As400 mainframe?

If you’re looking for examples of As400 mainframe computers, consider the universal automatic computer from the UNIVAC series, a ZSeries mainframe computer from IBM, and Non-Stop by Hewlett Packard. All three are excellent options to explore when searching for an As400 mainframe system.

AS/400 Mainframe
mainframe as400

Why is As 400 Mainframe used?

Corporations often choose IBM As 400 mainframes to host applications that require dependability and scalability. For example, financial institutions like banks turn to these powerful machines when it comes time to store their customer records in a secure database.

Is AS/400 Mainframe still used today?

Despite the massive technological advancements of recent times, AS400 Mainframes remain at the very core of large corporate operations, primarily in finance and airway companies. They continue to make a critical impact on day-to-day business activities.

Is an AS400 mainframe a database?

No, an As400 mainframe is not a database. It is a type of computer system that runs the Z operating system from IBM and provides robust management and security features. However, it can be used to host applications with databases in them. Despite the fact that an As 400 mainframe can be used both for hosting and connecting to a database, it is not itself considered a database.

What language does the mainframe use?

The primary language used by a mainframe is COBOL (Common Business Oriented Language). Other languages that can be used include Java, C/C++, and RPG. Additionally, some higher-level applications, such as IBM WebSphere and VisualAge, may be used on the As/400 Mainframe.


In conclusion, the As400 Mainframe is a powerful computer system that provides a secure and reliable platform for businesses. It features robust capabilities such as an IBM Z operating system, hardware management console, and compatibility with various programming languages. These attributes make it an ideal choice for organizations looking to host mission-critical applications. With its performance and stability, it can also be used to store customer records in a secure database. Overall, As/400 Mainframe is certainly worth considering when searching for a dependable computer system with superior security and reliability. Furthermore, its scalability makes it suitable for any size organization that requires the highest level of operational efficiency.

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