External links
 | This computer networking article is a stub. You can help Wikipedia by expanding it. |
VNET is an international computer networking system deployed in the mid-1970s and still in current, but highly diminished use. It was developed inside IBM and provided the main email and file-transfer backbone for the company throughout the 1980s and 1990s. Through it, a number of protocols were developed to deliver email amongst time sharing computers over alternative transmission systems.
VNET was first deployed as a private host to host network among CP/67 and VM/370 mainframes beginning before 1975. It was based on RSCS, a virtual machine–based communications program and an inter machine protocol developed in IBM's Advanced Systems Development Division's Remote Service System (RSS) prototype which produced some of the technology in the IBM Tivoli product. RSCS used the Binary Synchronous Communications (BSC) protocol, not SNA/SDLC, to support file to file transfer among virtual machine users. The first several nodes included Scientific Centers and Poughkeepsie, New York lab sites.
RSCS-compatible communications code was subsequently developed for MVT/HASP, MVT/ASP and MVS mainframe operating systems. By September 1979, the network had grown to include 285 mainframe nodes in Europe, Asia, and North America. Unlike the Internet, VNET switched files among mainframes using a store and forward technique. Many of the early connections operated over dial-up phone lines at speeds of 1200 to 2400 bits per second. The addition of a 19.2 kbit/s trans-Atlantic satellite circuit in late 1977 was considered a major step forward.
End users typically sent files between 100 and 100,000 bytes in length. The user could expect delivery within one minute to several hours. File delivery was acknowledged on a hop by hop basis but there was no end to end delivery confirmation. However, by the late 1970s an email application was developed that provided delivery confirmation as well as message archiving. What began as a research activity among engineers and scientists became, by 1980, a valuable business asset for many organizations within IBM.
The first widely disruptive computer worm, "Christmas Tree EXEC" in December 1987, originated on BITNET and spread to this network.
| | This computer networking article is a stub. You can help Wikipedia by expanding it. |
IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the large computer market. Current mainframe computers in IBM's line of business computers are developments of the basic design of the IBM System/360.
Systems Network Architecture (SNA) is IBM's proprietary networking architecture, created in 1974. It is a complete protocol stack for interconnecting computers and their resources. SNA describes formats and protocols and is, in itself, not a piece of software. The implementation of SNA takes the form of various communications packages, most notably Virtual Telecommunications Access Method (VTAM), the mainframe software package for SNA communications.
BITNET Relay, also known as the Inter Chat Relay Network, was a chat network setup over BITNET nodes. It predated Internet Relay Chat and other online chat systems. The program that made the network possible was called "Relay" and was developed by Jeff Kell of the University of Tennessee at Chattanooga in 1985 using the REXX programming language.
MUSIC/SP was developed at McGill University in the 1970s from an early IBM time-sharing system called RAX. The system ran on IBM S/360, S/370, and 4300-series mainframe hardware, and offered novel features such as file access control and data compression. It was designed to allow academics and students to create and run their programs interactively on terminals, in an era when most mainframe computing was still being done from punched cards. Over the years, development continued and the system evolved to embrace email, the Internet and eventually the World Wide Web. At its peak in the late 1980s, there were over 250 universities, colleges and high school districts that used the system in North and South America, Europe and Asia.
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.
Store and forward is a telecommunications technique in which information is sent to an intermediate station where it is kept and sent at a later time to the final destination or to another intermediate station. The intermediate station, or node in a networking context, verifies the integrity of the message before forwarding it. In general, this technique is used in networks with intermittent connectivity, especially in the wilderness or environments requiring high mobility. It may also be preferable in situations when there are long delays in transmission and variable and high error rates, or if a direct, end-to-end connection is not available.
Remote job entry is the procedure for sending requests for non-interactive data processing tasks (jobs) to mainframe computers from remote workstations, and by extension the process of receiving the output from such jobs at a remote workstation.
A computer network is a group of computers that use a set of common communication protocols over digital interconnections for the purpose of sharing resources located on or provided by the network nodes. The interconnections between nodes are formed from a broad spectrum of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies.
Christmas Tree EXEC was the first widely disruptive computer worm, which paralyzed several international computer networks in December 1987.
The IBM Cambridge Scientific Center was a company research laboratory established in February 1964 in Cambridge, Massachusetts. Situated at 545 Technology Square, in the same building as MIT's Project MAC, it was later renamed the IBM Scientific Center. It is most notable for creating the CP-40 and the control program portions of CP/CMS, a virtual machine operating system developed for the IBM System/360-67.
A clustered file system is a file system which is shared by being simultaneously mounted on multiple servers. There are several approaches to clustering, most of which do not employ a clustered file system. Clustered file systems can provide features like location-independent addressing and redundancy which improve reliability or reduce the complexity of the other parts of the cluster. Parallel file systems are a type of clustered file system that spread data across multiple storage nodes, usually for redundancy or performance.
The history of operating systems running on IBM mainframes is a notable chapter of history of mainframe operating systems, because of IBM's long-standing position as the world's largest hardware supplier of mainframe computers.
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB and Input/Output Control System (IOCS) packages for the IBM 7090/7094 and even more so by the PR155 Operating System for the IBM 1410/7010 processors. It was one of the earliest operating systems to require the computer hardware to include at least one direct access storage device.
A computer cluster is a set of loosely or tightly connected computers that work together so that, in many aspects, they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software.
BITNET was a co-operative U.S. university computer network founded in 1981 by Ira Fuchs at the City University of New York (CUNY) and Greydon Freeman at Yale University. The first network link was between CUNY and Yale.
TRICKLE was a file-forwarding service on the BITNET (EARN/NetNorth/GulfNet) network.
Remote Spooling Communications Subsystem or RSCS is a subsystem of IBM's VM/370 operating system which accepts files transmitted to it from local or remote system and users and transmits them to destination local or remote users and systems. RSCS also transmits commands and messages among users and systems.
Edson C. Hendricks, an IBM computer scientist, developed RSCS, fundamental software that powered the world’s largest network prior to the Internet and which directly influenced both Internet development and user acceptance of networking between independently managed organizations. Within IBM, the resulting network later became known as VNET and grew to 4000 nodes. In the academic community, VNET formed the base for BITNET which extended to 500 organizations and 3,000 nodes. VNET was also the networking design underpinning EARN in Europe, and NETNORTH in Canada.
The European Academic and Research Network (EARN) was a computer network connecting universities and research institutions across Europe, and was connected in 1983 via transatlantic circuits and a gateway funded by IBM to BITNET, its peer in the United States.
The history of email extends over more than 50 years, entailing an evolving set of technologies and standards that culminated in the email systems in use today.