IBM System/370

IBM System/370 is a family of mainframe computers developed by IBM and announced on June 30, 1970, as the successor to the IBM System/360. The System/370 was designed to be compatible with the System/360, allowing customers to upgrade their existing systems with minimal changes to their software and applications, similar to the approach taken by Microsoft with its Windows operating system and Intel with its x86 processors. The System/370 was widely used by large corporations, government agencies, and universities, including Harvard University, Stanford University, and Massachusetts Institute of Technology. It played a significant role in the development of the computer industry, influencing companies like Hewlett-Packard, Digital Equipment Corporation, and Unisys.

Introduction

The IBM System/370 was a major milestone in the development of mainframe computing, building on the success of the System/360 and incorporating new technologies and innovations, such as virtual memory and cache memory, developed by IBM Research and Bell Labs. The System/370 was designed to support a wide range of applications, from simple batch processing to complex online transaction processing systems, used by companies like American Airlines, United Airlines, and Bank of America. It was also used by NASA for space exploration and by the US Department of Defense for military operations. The System/370 was widely adopted by organizations around the world, including European Union institutions, Japanese government agencies, and Australian universities.

Architecture

The IBM System/370 architecture was based on a 32-bit processor with a byte-addressable memory, similar to the PDP-11 and VAX architectures developed by Digital Equipment Corporation. The System/370 used a bus-oriented architecture, with a system bus that connected the central processing unit (CPU) to the memory and input/output (I/O) devices, designed by IBM Federal Systems Division and IBM Storage Systems Division. The System/370 also introduced a new instruction set architecture (ISA) that was compatible with the System/360 ISA, allowing customers to run their existing software on the new system, including applications developed by SAP, Oracle Corporation, and Microsoft. The System/370 architecture was influenced by the work of computer scientists like Alan Turing, John von Neumann, and Donald Knuth, and was used in systems developed by Cray Research, Control Data Corporation, and Burroughs Corporation.

Models

The IBM System/370 family included a range of models, from the low-end System/370 Model 115 to the high-end System/370 Model 195, each with its own unique characteristics and capabilities, similar to the IBM System z and IBM Power Systems families. The System/370 models were designed to support different types of applications and workloads, from small-scale batch processing to large-scale online transaction processing systems, used by companies like Visa, Mastercard, and American Express. The System/370 models were also used by research institutions, such as CERN, Los Alamos National Laboratory, and Lawrence Livermore National Laboratory, and by government agencies, including the US Department of Energy, US Department of Commerce, and National Security Agency.

Operating Systems

The IBM System/370 supported a range of operating systems, including MVS (Multiple Virtual Storage), VM (Virtual Machine), and VSE (Virtual Storage Extended), developed by IBM Software Group and IBM Research. These operating systems provided a range of features and functions, including virtual memory, multiprogramming, and job scheduling, similar to the Unix and Linux operating systems developed by Bell Labs and Linus Torvalds. The System/370 operating systems were designed to support a wide range of applications, from simple batch processing to complex online transaction processing systems, used by companies like IBM Global Services, Accenture, and Deloitte. The System/370 operating systems were also used by universities, such as University of California, Berkeley, University of Michigan, and Carnegie Mellon University, and by research institutions, including MIT Lincoln Laboratory and Sandia National Laboratories.

Applications and Impact

The IBM System/370 had a significant impact on the development of the computer industry, influencing the design of subsequent mainframe computers and supercomputers, such as the Cray-1 and IBM Blue Gene. The System/370 was used in a wide range of applications, from financial transactions to scientific simulations, including weather forecasting and climate modeling developed by National Oceanic and Atmospheric Administration and National Center for Atmospheric Research. The System/370 was also used by government agencies, such as the US Census Bureau and Social Security Administration, and by healthcare organizations, including Mayo Clinic and Cleveland Clinic. The System/370 played a significant role in the development of the internet, with many of the first network protocols and network architectures being developed on System/370 systems, including TCP/IP and HTTP developed by Vint Cerf and Tim Berners-Lee.

Legacy and Withdrawal

The IBM System/370 was eventually replaced by the IBM System/390 and IBM zSeries families, which offered improved performance, scalability, and reliability, similar to the IBM Power Systems and IBM Storage Systems families. The System/370 was withdrawn from marketing in the 1990s, but many of its legacy systems remain in use today, supporting critical applications and workloads, including air traffic control and financial transactions developed by Federal Aviation Administration and Federal Reserve System. The System/370 has had a lasting impact on the development of the computer industry, influencing the design of subsequent mainframe computers and supercomputers, and its legacy continues to be felt in the modern data center and cloud computing environments, including Amazon Web Services, Microsoft Azure, and Google Cloud Platform. The System/370 has also influenced the development of artificial intelligence and machine learning systems, including IBM Watson and Google DeepMind. Category:Mainframe computers