Network Control Program

Network Control Program
This article is about the ARPANET Network Control Program. For Novell NetWare protocol, see NetWare Core Protocol. For the IBM Network Control Program software, see IBM Network Control Program.

The Network Control Program (NCP) provided the middle layers of the protocol stack running on host computers of the ARPANET, the predecessor to the modern Internet. Although sometimes the abbreviation NCP is mistakenly expanded to Network Control Protocol, this term is not found in the contemporaneous documentation.

Contents

History

NCP provided connections and flow control between processes running on different ARPANET host computers. Application services, such as email and file transfer, were built on top of NCP, using it to handle connections to other host computers.

On the ARPANET, the protocols in the Physical Layer, the Data Link Layer, and the Network Layer used within the network were implemented on separate Interface Message Processors (IMPs). The host usually connected to an IMP using another kind of interface, with different physical, data link and network layer specifications. The IMP's capabilities were specified by the Host/IMP Protocol in BBN Report 1822.

Since lower protocol layers were provided by the IMP-host interface, NCP essentially provided a Transport Layer consisting of the ARPANET Host-to-Host Protocol (AHHP) and the Initial Connection Protocol (ICP). AHHP defined procedures to transmit a unidirectional, flow-controlled data stream between two hosts. The ICP defined the procedure for establishing a bidirectional pair of such streams between a pair of host processes. Application protocols (e.g., FTP) accessed network services through an interface to the top layer of the NCP, a forerunner to the Berkeley sockets interface.

Transition to TCP/IP

On January 1, 1983, known as flag day, NCP was officially rendered obsolete when the ARPANET changed its core networking protocols from NCP to the more flexible and powerful TCP/IP protocol suite, marking the start of the modern Internet.[1]

Notes

  1. ^ Postel, J. (November 1981). "The General Plan". NCP/TCP transition plan. IETF. p. 2. RFC 801. http://tools.ietf.org/html/rfc801#page-2. Retrieved February 1, 2011. 

Further reading

  • S. Crocker (16 March 1970). Protocol Notes. RFC 36. Network Working Group (now IETF). 
  • Postel, Jon; Feinler, E. (1978). ARPANET Protocol Handbook. Menlo Park, CA: Network Information Center. 
  • BBN (May 1978). Interface Message Processor -- Specifications for the Interconnection of a Host and an IMP. BBN Report 1822. Bolt, Beranek, and Newman, Inc.. 

Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Network Control Program — (IBM) Pour les articles homonymes, voir NCP. Le Network Control Program (NCP), est un logiciel autonome exécuté par l unité de communication associé à l ordinateur central. Il assure la gestion de l ensemble des liaisons avec les stations et… …   Wikipédia en Français

  • Network Control Program (Arpanet) — Pour les articles homonymes, voir NCP. Network Control Program (NCP) est un protocole de communication poste à poste opérationnel en 1970 et adopté entre 1971 et 1972 pour le transfert de données via le réseau Arpanet. Ce protocole devint… …   Wikipédia en Français

  • Network Control Program (IBM) — Pour les articles homonymes, voir NCP. Le Network Control Program (NCP), est un logiciel autonome exécuté par l unité de communication associé à l ordinateur central. Il assure la gestion de l ensemble des liaisons avec les stations et terminaux… …   Wikipédia en Français

  • network control program —    Abbreviated NCP. In an IBM Systems Network Architecture (SNA) environment, performs the routing, error control, testing, and addressing of SNA devices …   Dictionary of networking

  • Network Control Program —    (NCP)    Software that runs on IBM communications controllers, such as the 3725, to manage the network and support the host interface to the network …   IT glossary of terms, acronyms and abbreviations

  • IBM Network Control Program — The IBM Network Control Program (NCP) ran on an IBM 3704, 3705 or 3745. It caused the machine to become a Systems Network Architecture (SNA) Physical Unit Type 4 (PU4). A PU4 usually had SDLC links to remote cluster controllers (PU1/PU2) and… …   Wikipedia

  • Network Control Protocol — Das Protokoll NCP (Network Control Protocol) ist eine Komponente des Point to Point Protokolls (PPP) und dient für die Verhandlungsoptionen zwischen beiden Enden einer Punkt zu Punkt Verbindung. Gemeint sind also Steuerprotokolle, die zwischen… …   Deutsch Wikipedia

  • Network Control Protocol — This article is about protocols running atop the Point to Point Protocol for negotiating network layer protocol options. For the ARPANET NCP, see Network Control Program. A Network Control Protocol is a protocol that runs atop the Point to Point… …   Wikipedia

  • Network Crack Program Hacker (NCPH) Group — Formation 1994 (1994) Type hacker group Location Sichuan Province, China Membership 4 core members, aprox. 10 members ( …   Wikipedia

  • remote-control program —    A program that allows the user to link two PCs together so that one of the computers controls the operation of the other. The connection may be over a dedicated serial line, a local area network, or a modem to modem communications link. Each… …   Dictionary of networking

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”