International Networking Working Group

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The International Networking Working Group (INWG) was a group of prominent computer science researchers in the 1970s who studied and developed standards and protocols for computer networking. Set up in 1972 as an informal group to consider the technical issues involved in connecting different networks, its charter was to develop international standard protocols for internetworking. INWG became a subcommittee of the International Federation for Information Processing (IFIP) two years later. Concepts developed by members of the group contributed to the original "Protocol for Packet Network Intercommunication" proposed by Vint Cerf and Bob Kahn in 1974 and the Transmission Control Protocol and Internet Protocol (TCP/IP) that emerged later.



The International Networking Working Group formed in October 1972 at the International Conference on Computer Communication held in Washington D.C. Its purpose was to study and develop "international standard protocols for internetworking". [1] The group was modelled on the ARPANET "Networking Working Group" created by Steve Crocker. [2]

Vint Cerf was the first Chair of the INWG. Other active members included Alex McKenzie, Donald Davies, Roger Scantlebury, Louis Pouzin and Hubert Zimmermann. [3] [4] [5] These researchers represented the American ARPANET, [nb 1] the French CYCLADES project, and the British team working on the NPL network and European Informatics Network. [3] In January 1974 Pouzin arranged affiliation with the International Federation for Information Processing (IFIP). [1] INWG became IFIP Working Group 1 under Technical Committee 6 (Data Communication) with the title "International Packet Switching for Computer Sharing" (WG6.1). This standing, although informal, enabled the group to provide technical input on packet networking to CCITT and ISO. [3] [5] [6] [7] [8]

In September 1973, Vint Cerf and Bob Kahn (who was not a member of INWG) gave a paper at an INWG meeting at the University of Sussex in England. Their ideas were refined further in long discussions with Davies, Scantlebury, Pouzin and Zimmerman. [9] Louis Pouzin introduced the term catenet , the original term for an interconnected network, in October 1973. [3] Zimmerman published a paper "Standard host-host protocol for heterogeneous computer networks" in April 1974, [10] and Pouzin published a May 1974 paper "A Proposal for Interconnecting Packet Switching Networks". [11] Kahn and Vint Cerf also published their proposal in May 1974, "A Protocol for Packet Network Intercommunication", which introduced the term internet as a shorthand for internetwork. The paper acknowledged several members of the INWG. [12]

The Internet architecture as seen by the INWG. INWG-arch.png
The Internet architecture as seen by the INWG.

Over three years, the group shared numerous numbered 'notes'. There were two competing proposals, [14] INWG 37 based on the early Transmission Control Program proposed by Kahn and Cerf (updated in INWG 72), [15] and INWG 61 based on the CYCLADES TS (transport station) protocol proposed by Pouzin and Zimmermann. There were two sticking points (how fragmentation should work; and whether the data flow was an undifferentiated stream or maintained the integrity of the units sent). These were not major differences and after "hot debate" a synthesis was proposed in INWG 96. [3] [13] [16]

This protocol, agreed by the group in 1975, titled "Proposal for an international end to end protocol", was written by Vint Cerf, Alex McKenzie, Roger Scantlebury, and Hubert Zimmermann. [17] [18] [19] It was presented to the CCIT in 1976 by Derek Barber, who became INWG chair earlier that year. Although the protocol was adopted by networks in Europe, [20] it was not adopted by the CCIT nor by the ARPANET.

CCIT went on to adopt the X.25 standard in 1976, based on virtual circuits, and ARPA ultimately developed the Internet protocol suite, including the Internet Protocol as connectionless layer and the Transmission Control Protocol as a reliable connection-oriented service, which incorporated concepts from the French CYCLADES project. [21]

Alex McKenzie served as chair from 1979-1982 and Secretary beginning in 1983. [1] Later international work led to the OSI model in 1984, of which many members of the INWG became advocates. [4] During the 'Protocol Wars' of the late 1980s and early 1990s, engineers, organizations and nations became polarized over the issue of which standard, the OSI model or the Internet protocol suite would result in the best and most robust computer networks. ARPA partnerships with the telecommunication and computer industry led to widespread private sector adoption of the Internet protocol suite as a communication protocol. [4] [22] [23]

The INWG continued to work on protocol design and formal specification until the 1990s when it disbanded as the Internet grew rapidly. [3] Nonetheless, issues with the Internet Protocol suite remain and alternatives have been proposed building on INWG ideas such as Recursive Internetwork Architecture. [13]


The group had about 100 members, including the following: [3] [7]

See also


  1. Specifically, McKenzie represented BBN and Cerf represented Stanford University.

Related Research Articles

Internetworking is the practice of interconnecting multiple computer networks, such that any pair of hosts in the connected networks can exchange messages irrespective of their hardware-level networking technology. The resulting system of interconnected networks are called an internetwork, or simply an internet.

The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet.

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). In the development of this networking model, early versions of it 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.

<span class="mw-page-title-main">Vint Cerf</span> American computer scientist

Vinton Gray Cerf is an American Internet pioneer and is recognized as one of "the fathers of the Internet", sharing this title with TCP/IP co-developer Bob Kahn. He has received honorary degrees and awards that include the National Medal of Technology, the Turing Award, the Presidential Medal of Freedom, the Marconi Prize, and membership in the National Academy of Engineering.

A datagram is a basic transfer unit associated with a packet-switched network. Datagrams are typically structured in header and payload sections. Datagrams provide a connectionless communication service across a packet-switched network. The delivery, arrival time, and order of arrival of datagrams need not be guaranteed by the network.

<span class="mw-page-title-main">Packet switching</span> Method for transmitting data over a computer network

In telecommunications, packet switching is a method of grouping data into packets that are transmitted over a digital network. Packets are made of a header and a payload. Data in the header is used by networking hardware to direct the packet to its destination, where the payload is extracted and used by an operating system, application software, or higher layer protocols. Packet switching is the primary basis for data communications in computer networks worldwide.

<span class="mw-page-title-main">National Physical Laboratory (United Kingdom)</span> National Measurement Institution of the United Kingdom

The National Physical Laboratory (NPL) is the national measurement standards laboratory of the United Kingdom. It is one of the most extensive government laboratories in the UK and has a prestigious reputation for its role in setting and maintaining physical standards for British industry.

<span class="mw-page-title-main">ARPANET</span> Early packet switching network (1969–1990), one of the first to implement TCP/IP

The Advanced Research Projects Agency Network (ARPANET) was the first wide-area packet-switched network with distributed control and one of the first networks to implement the TCP/IP protocol suite. Both technologies became the technical foundation of the Internet. The ARPANET was established by the Advanced Research Projects Agency (ARPA) of the United States Department of Defense.

<span class="mw-page-title-main">Bob Kahn</span> American Internet pioneer, computer scientist

Robert Elliot Kahn is an American electrical engineer who, along with Vint Cerf, first proposed the Transmission Control Protocol (TCP) and the Internet Protocol (IP), the fundamental communication protocols at the heart of the Internet.

<span class="mw-page-title-main">Donald Davies</span> Welsh computer scientist (1924–2000)

Donald Watts Davies, was a Welsh computer scientist who was employed at the UK National Physical Laboratory (NPL).

The CYCLADES computer network was a French research network created in the early 1970s. It was one of the pioneering networks experimenting with the concept of packet switching and, unlike the ARPANET, was explicitly designed to facilitate internetworking.

<span class="mw-page-title-main">Louis Pouzin</span> French computer scientist (born 1931)

Louis Pouzin is a French computer scientist. He designed an early packet communications network, CYCLADES.

Hubert Zimmermann was a French software engineer and a pioneer of computer networking.

Peter Thomas Kirstein was a British computer scientist who played a role in the creation of the Internet. He put the first computer on the ARPANET outside of the US and was instrumental in defining and implementing TCP/IP alongside Vint Cerf and Bob Kahn.

A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics and synchronization of communication and possible error recovery methods. Protocols may be implemented by hardware, software, or a combination of both.

<span class="mw-page-title-main">NPL network</span> Historical network in England pioneering packet switching

The NPL network, or NPL Data Communications Network, was a local area computer network operated by a team from the National Physical Laboratory in London that pioneered the concept of packet switching.

<span class="mw-page-title-main">SATNET</span> Early computer network that used satellite communication

SATNET, also known as the Atlantic Packet Satellite Network, was an early satellite network that formed an initial segment of the Internet. It was implemented by BBN Technologies under the direction of the Advanced Research Projects Agency.

Roger Anthony Scantlebury is a British computer scientist who worked at the National Physical Laboratory (NPL) and later at Logica.

A long-running debate in computer science known as the Protocol Wars occurred from the 1970s to the 1990s when engineers, organizations and nations became polarized over the issue of which communication protocol would result in the best and most robust computer networks. This culminated in the Internet–OSI Standards War in the late 1980s and early 1990s, which was ultimately "won" by the Internet protocol suite ("TCP/IP") by the mid-1990s and has since resulted in most other protocols disappearing.


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  13. 1 2 3 J. Day. How in the Heck Do You Lose a Layer!? 2nd IFIP International Conference of the Network of the Future, Paris, France, 2011
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Further reading