A file manager or file browser is a computer program that provides a user interface to manage files and folders. The most common operations performed on files or groups of files include creating, opening, renaming, copying, moving, deleting and searching for files, as well as modifying file attributes, properties and file permissions. Folders and files may be displayed in a hierarchical tree based on their directory structure.
The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and the Internet Protocol (IP). Early versions of this networking model were known as the Department of Defense (DoD) model because the research and development were funded by the United States Department of Defense through DARPA.
The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and data connections between the client and the server. FTP users may authenticate themselves with a plain-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. For secure transmission that protects the username and password, and encrypts the content, FTP is often secured with SSL/TLS (FTPS) or replaced with SSH File Transfer Protocol (SFTP).
The Conversational Monitor System is a simple interactive single-user operating system. CMS was originally developed as part of IBM's CP/CMS operating system, which went into production use in 1967. CMS is part of IBM's VM family, which runs on IBM mainframe computers. VM was first announced in 1972, and is still in use today as z/VM.
VM is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible systems, including the Hercules emulator for personal computers.
CP/CMS is a discontinued time-sharing operating system of the late 1960s and early 1970s. It is known for its excellent performance and advanced features. Among its three versions, CP-40/CMS was an important 'one-off' research system that established the CP/CMS virtual machine architecture. It was followed by CP-67/CMS, a reimplementation of CP-40/CMS for the IBM System/360-67, and the primary focus of this article. Finally, CP-370/CMS was a reimplementation of CP-67/CMS for the System/370. While it was never released as such, it became the foundation of IBM's VM/370 operating system, announced in 1972.
Server Message Block (SMB) is a communication protocol used to share files, printers, serial ports, and miscellaneous communications between nodes on a network. On Microsoft Windows, the SMB implementation consists of two vaguely named Windows services: "Server" and "Workstation". It uses NTLM or Kerberos protocols for user authentication. It also provides an authenticated inter-process communication (IPC) mechanism.
z/VM is the current version in IBM's VM family of virtual machine operating systems. z/VM was first released in October 2000 and remains in active use and development as of 2022. It is directly based on technology and concepts dating back to the 1960s, with IBM's CP/CMS on the IBM System/360-67. z/VM runs on IBM's IBM Z family of computers. It can be used to support large numbers (thousands) of Linux virtual machines.
A hypervisor, also known as a virtual machine monitor (VMM) or virtualizer, is a type of computer software, firmware or hardware that creates and runs virtual machines. A computer on which a hypervisor runs one or more virtual machines is called a host machine, and each virtual machine is called a guest machine. The hypervisor presents the guest operating systems with a virtual operating platform and manages the execution of the guest operating systems. Unlike an emulator, the guest executes most instructions on the native hardware. Multiple instances of a variety of operating systems may share the virtualized hardware resources: for example, Linux, Windows, and macOS instances can all run on a single physical x86 machine. This contrasts with operating-system–level virtualization, where all instances must share a single kernel, though the guest operating systems can differ in user space, such as different Linux distributions with the same kernel.
In computing, Advanced Program to Program Communication or APPC is a protocol which computer programs can use to communicate over a network. APPC is at the application layer in the OSI model, it enables communications between programs on different computers, from portables and workstations to midrange and host computers. APPC is defined as VTAM LU 6.2
Since the rise of the personal computer in the 1980s, IBM and other vendors have created PC-based IBM-compatible mainframes which are compatible with the larger IBM mainframe computers. For a period of time PC-based mainframe-compatible systems had a lower price and did not require as much electricity or floor space. However, they sacrificed performance and were not as dependable as mainframe-class hardware. These products have been popular with mainframe developers, in education and training settings, for very small companies with non-critical processing, and in certain disaster relief roles.
Connect:Direct—originally named Network Data Mover (NDM)—is a computer software product that transfers files between mainframe computers and/or midrange computers. It was developed for mainframes, with other platforms being added as the product grew. NDM was renamed to Connect:Direct in 1993, following the acquisition of Systems Center, Inc. by Sterling Software. In 1996, Sterling Software executed a public spinoff of a new entity called Sterling Commerce, which consisted of the Communications Software Group (the business unit responsible for marketing the Connect:Direct product and other file transfer products sourced from the pre-1993 Sterling Software (e.g. Connect:Mailbox)) and the Sterling EDI Network business. In 2000, SBC Communications acquired Sterling Commerce and held it until 2010. AT&T merged with SBC effective November 2005. In 2010, IBM completed the purchase of Sterling Commerce from AT&T.
VP/CSS was a time-sharing operating system developed by National CSS. It began life in 1968 as a copy of IBM's CP/CMS, which at the time was distributed to IBM customers at no charge, in source code form, without support, as part of the IBM Type-III Library. Through extensive in-house development, in what today would be termed a software fork, National CSS took VP/CSS in a different direction from CP/CMS. Although the two systems would eventually share many capabilities, their technical implementations diverged in substantive ways.
The following is a timeline of virtualization development. In computing, virtualization is the use of a computer to simulate another computer. Through virtualization, a host simulates a guest by exposing virtual hardware devices, which may be done through software or by allowing access to a physical device connected to the machine.
CP-40 was a research precursor to CP-67, which in turn was part of IBM's then-revolutionary CP[-67]/CMS – a virtual machine/virtual memory time-sharing operating system for the IBM System/360 Model 67, and the parent of IBM's VM family. CP-40 ran multiple instances of client operating systems – particularly CMS, the Cambridge Monitor System, built as part of the same effort. Like CP-67, CP-40 and the first version of CMS were developed by IBM's Cambridge Scientific Center (CSC) staff, working closely with MIT researchers at Project MAC and Lincoln Laboratory. CP-40/CMS production use began in January 1967. CP-40 ran on a unique, specially modified IBM System/360 Model 40.
This article covers the History of CP/CMS — the historical context in which the IBM time-sharing virtual machine operating system was built.
The history of IBM mainframe operating systems is significant within the history of mainframe operating systems, because of IBM's long-standing position as the world's largest hardware supplier of mainframe computers. IBM mainframes run operating systems supplied by IBM and by third parties.
Barry Appelman is recognized as being the father of the "buddy list" and AOL instant messenger. Companies had been using crude forms of Instant messaging within their own networks for over forty years, but the idea of presence, i.e. who is logged on at any given time, was non existent. It was not until Appelman, and his colleagues at the Thomas Watson Research Center, first began to write programs on the mainframe system letting each other know when they were actually online, that modern day Instant Messaging was born.
S2 Spreadsheet was a Lotus 1-2-3 compatible spreadsheet developed by IBM in 1984. It had all the features of Lotus 1-2-3, plus it had an ability to connect to IBM mainframes via TCP/IP and pull data from IBM databases such as IBM DB2 and IBM SQL/DS. It also had features that allowed for easy visual connection between formulas and their dependencies - those features were later adopted by Lotus 1-2-3 and Microsoft Excel. S2 was developed almost concurrently with Lotus development of 1-2-3, and matched 1-2-3 feature for feature. The S2 program was used throughout IBM in 1980s and 1990s. In 1986 it caused a legal controversy within IBM because of then current look-and-feel lawsuits between Lotus and other companies, and most importantly because IBM was negotiating a high-profile deal with Lotus to market Lotus 1-2-3.
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