Mainframe computers are crucial to some of the world’s largest corporations. Every mainframe has more than one modern processor, RAM ranging from a few megabytes to several gigabytes, and disk space and other storage beyond anything in a microcomputer. A mainframe can handle multiple tasks and serve thousands of users every second without downtime.
The main difference between mainframes and other computer systems is the level of processing that takes place. Mainframes are also different in terms of data bandwidth, organization, reliability, and control. Large organizations (banking, healthcare, insurance, and telecommunications companies, etc.) use mainframes to process critical business data.
In this article, we discuss the evolution of mainframe computers and their components.
History of mainframe computers
IBM developed a crucial part of mainframe computing, the Automatic Sequence Controlled Calculator (ASCC) for arithmetic operations, in 1944. From the late 1950s through the 1970s, several companies made mainframes: IBM, Burroughs, RCA, NCR, General Electric and Sperry. Randy, for example. Since then, IBM’s System/390 is the only type of mainframe in use. It evolved from IBM’s System/360 in 1960.
An Early mainframe took up a huge space. New technologies have drastically reduced the size and cost of hardware. A current generation mainframe can fit in a small closet.
Components of a modern mainframe computer
Like a PC, a mainframe has many components to process data: operating system, motherboard or main board, processor, controllers, storage devices, and channels.
• Motherboard – A mainframe computer’s motherboard consists of a printed circuit that allows the CPU, RAM, and other hardware components to work together through a concept called “bus architecture.” The motherboard has device slots for input cards and cable interfaces for various external devices. Where PC motherboards use 32-bit or 64-bit buses, mainframes use 128-bit buses. General internal architecture instructions help the motherboard connect to other devices and retrieve data using binary computation.
• Processor – A CPU acts as the central processing point in the mainframe architecture and includes an arithmetic logic unit (ALU) to perform arithmetic calculations. It also functions as a controller for the bus architecture and manages traffic and data requests. The processing power of mainframes is much higher compared to PCs, so they can handle large amounts of data.
• Storage Devices: Storage devices are for entering, retrieving, storing, and recording data. Many are external devices, such as hard drives, tape drives, and punch card readers, all connected to mainframe terminals and controlled by the CPU. Its data storage capacity can be a hundred or even thousands of times greater than that of a PC.
• Communication drivers: Communication drivers allow remote computers to access a mainframe. With the help of networks, LANs or WANs, communication controllers establish connections with various devices, perform data transmission over communication channels, and keep track of users at terminals.
• Channels: “Channels” are the cables used to connect the CPU and main storage to other parts of the system and ensure that data moves consistently without losing its integrity.
Modern mainframes have advanced features such as expanded service management capabilities, cross-platform integration facilities, etc. and are therefore suitable for critical data center operations. The maintenance cost of modern mainframes is much lower compared to older models.