Datakit
Encyclopedia
Datakit is a virtual circuit
switch which was developed at Bell Labs
for both local-area and wide-area networks, and in widespread deployment by the Regional Bell Operating Companies (RBOCs).
Datakit uses a cell relay
packet similar to X.25
. Datakit is a connection-oriented switch; hence all packets for a particular call travel through the network over the same virtual circuit
. Datakit networks are still in widespread use by the major telephone companies in the United States.
Interfaces to these networks include TCP/IP and UDP, X.25, asynchronous protocols and several synchronous protocols, such as SDLC
, HDLC, Bisync and others. These networks support host to terminal traffic and vice-versa, host-to-host traffic, file transfers, remote login, remote printing, and remote command execution. At the physical layer
, it can operate over multiple media, from slow speed EIA-232 to 500Mbit fiber optic links including 10/100 Megabit ethernet links.
Most of Bell Laboratories was trunked together via Datakit networking. On top of Datakit transport service, several operating systems (including UNIX
) implemented UUCP
for electronic mail and dkcu for remote login.
Datakit uses a cell relay protocol called Universal Receiver Protocol (URP) that spreads PDU overhead across multiple packets and performs immediate packet processing. URP assumes that packets arrive in order and may force retransmissions if not.
The Information Systems Network (ISN) was the version of Datakit that was supported by the former AT&T Information Systems
. Datakit is supported today by Datatek Applications, Inc. under license from Alcatel-Lucent
Inc., the present owner of Bell Labs.
Virtual circuit
In telecommunications and computer networks, a virtual circuit , synonymous with virtual connection and virtual channel, is a connection oriented communication service that is delivered by means of packet mode communication...
switch which was developed at Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
for both local-area and wide-area networks, and in widespread deployment by the Regional Bell Operating Companies (RBOCs).
Datakit uses a cell relay
Cell relay
In computer networking, cell relay refers to a method of statistically multiplexing small fixed-length packets, called "cells", to transport data between computers or kinds of network equipment. It is an unreliable, connection-oriented packet switched data communications protocol.Cell relay...
packet similar to X.25
X.25
X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...
. Datakit is a connection-oriented switch; hence all packets for a particular call travel through the network over the same virtual circuit
Virtual circuit
In telecommunications and computer networks, a virtual circuit , synonymous with virtual connection and virtual channel, is a connection oriented communication service that is delivered by means of packet mode communication...
. Datakit networks are still in widespread use by the major telephone companies in the United States.
Interfaces to these networks include TCP/IP and UDP, X.25, asynchronous protocols and several synchronous protocols, such as SDLC
SDLC
SDLC can refer to:* Systems Development Life Cycle, known also as "System Design Life Cycle"* "Software Development Life Cycle" synonym to Software development process* Synchronous Data Link Control, an IBM Protocol...
, HDLC, Bisync and others. These networks support host to terminal traffic and vice-versa, host-to-host traffic, file transfers, remote login, remote printing, and remote command execution. At the physical layer
Physical layer
The physical layer or layer 1 is the first and lowest layer in the seven-layer OSI model of computer networking. The implementation of this layer is often termed PHY....
, it can operate over multiple media, from slow speed EIA-232 to 500Mbit fiber optic links including 10/100 Megabit ethernet links.
Most of Bell Laboratories was trunked together via Datakit networking. On top of Datakit transport service, several operating systems (including UNIX
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
) implemented UUCP
UUCP
UUCP is an abbreviation for Unix-to-Unix Copy. The term generally refers to a suite of computer programs and protocols allowing remote execution of commands and transfer of files, email and netnews between computers. Specifically, a command named uucp is one of the programs in the suite; it...
for electronic mail and dkcu for remote login.
Datakit uses a cell relay protocol called Universal Receiver Protocol (URP) that spreads PDU overhead across multiple packets and performs immediate packet processing. URP assumes that packets arrive in order and may force retransmissions if not.
The Information Systems Network (ISN) was the version of Datakit that was supported by the former AT&T Information Systems
AT&T Information Systems
AT&T Information Systems was the fully separate subsidiary of AT&T which focused on computer technology ventures and telephone sales, and other unregulated business...
. Datakit is supported today by Datatek Applications, Inc. under license from Alcatel-Lucent
Alcatel-Lucent
Alcatel-Lucent is a global telecommunications corporation, headquartered in the 7th arrondissement of Paris, France. It provides telecommunications solutions to service providers, enterprises, and governments around the world, enabling these customers to deliver voice, data, and video services...
Inc., the present owner of Bell Labs.