CYCLADES
TheCYCLADEScomputer network(French pronunciation:[siklad]) was a French research network created in the early 1970s. It was one of the pioneering networks experimenting with the concept ofpacket switchingand, unlike theARPANET,was explicitly designed to facilitateinternetworking.[1][2]
The CYCLADES network was the first to make thehostsresponsible for the reliable delivery of data, rather than this being a centralized service of the network itself.Datagramswere exchanged on the network using transport protocols that do not guarantee reliable delivery, but only attempt best-effort. To empower the network leaves the hosts to perform error-correction, the network ensured end-to-end protocol transparency, a concept later to be known as theend-to-end principle.This simplified network design, reduced network latency, and reduced the opportunities for single point failures. The experience with these concepts led to the design of key features of theInternet Protocolin the ARPANET project.[3][4][5]
The network was sponsored by the French government, through theInstitut de Recherche en lnformatique et en Automatique(IRIA), the national research laboratory for computer science in France, now known asInria,which served as the co-ordinating agency. Several French computer manufacturers, research institutes and universities contributed to the effort. CYCLADES was designed and directed byLouis Pouzin.[6][7]
Conception and deployment
[edit]Planning for the project began in 1971.[8][9]Design and staffing started in 1972, and November 1973 saw the first demonstration, using three hosts and onepacket switch.[10]
Pouzin coined the termcatenetin 1973, in a note circulated to theInternational Network Working Group,[11]to describe a system of packet-switched communication networks interconnected viagateways.He later published these ideas in a 1974 paper "A Proposal for Interconnecting Packet Switching Networks ".[12]
Deployment of the network continued in 1974, with three packet switches installed by February, although at that point the network was only operational for three hours each day. By June the network was up to seven switches, and was available throughout the day for experimental use.
A terminal concentrator was also developed that year, sincetime-sharingwas still a prevalent mode of computer use. In 1975, the network shrank slightly due to budgetary constraints, but the setback was only temporary. At that point, the network providedremote login,remote batchandfile transferuser application services.
By 1976 the network was in full deployment, eventually numbering 20 nodes with connections toNPLin London,ESAin Rome, and to theEuropean Informatics Network(EIN).
Technical details
[edit]CYCLADES used a layered architecture, which was adopted in the Internet. The basicpackettransmission like function, named CIGALE, was novel; it provided an unreliabledatagramservice(the word was coined by Louis Pouzin by combiningdataandtelegram). Since the packet switches no longer had to ensure correct delivery of data, this greatly simplified their design.[13]
“The inspiration for datagrams had two sources. One wasDonald Davies' studies. He had done some simulation of datagram networks, although he had not built any, and it looked technically viable. The second inspiration was I like things simple. I didn't see any real technical motivation to overlay two levels of end-to-end protocols. I thought one was enough.”
— Louis Pouzin[4]
The CIGALE network featured adistance vectorrouting protocol,and allowed experimentation with various metrics. it also included a time synchronization protocol in all the packet switches. CIGALE included early attempts at performing congestion control by dropping excess packets.
The name CIGALE (French pronunciation:[siɡal]) –Frenchforcicada– originates from the fact that the developers installed a speaker at each computer, so that "it went 'chirp chirp chirp' like cicadas" when a packet passed a computer.[14]
An end-to-end protocol built on top of that provided a reliabletransportservice, on top of which applications were built. It provided a reliable sequence of user-visible data units calledletters,rather than thereliable byte streamof TCP. The transport protocol was able to deal with out-of-order and unreliable delivery of datagrams, using the now-standard mechanisms of end-end acknowledgments and timeouts; it also featured sliding windows and end-to-end flow control.
Demise
[edit]By 1976, the FrenchPTTwas developingTranspac,a packet network based on the emergingX.25standard. The academic debates between datagram andvirtual circuitnetworks continued for some time, but were eventually cut short by bureaucratic decisions.
Data transmission was a state monopoly in France at the time, and IRIA needed a special dispensation to run the CYCLADES network. The PTT did not agree to funding by the government of a competitor to their Transpac network, and insisted that the permission and funding be rescinded. By 1981, Cyclades was forced to shut down.[8]
Legacy
[edit]The most important legacy of CYCLADES was in showing that moving the responsibility for reliability into the hosts was workable, and produced a well-functioning service network. It also showed that it greatly reduced the complexity of the packet switches. The concept became a cornerstone in the design of the Internet.[3][4][5][15][16]
The network was a fertile ground for experimentation, and allowed a generation of French computer scientists to experiment with networking concepts.[2]Louis Pouzin and the CYCLADES alumni initiated a number of follow-on projects at IRIA to experiment withlocal area networks,satellite networks,theUnixoperating system,and the message passing operating systemChorus.
Hubert Zimmermannused his experience in CYCLADES to influence the design of theOSI model,which is still a common pedagogical tool.
Gérard Le Lannworked withVint CerfandBob Kahnto incorporate concepts from the CYCLADES project into the original design of theTransmission Control Program.[17]
CYCLADES alumni and researchers at IRIA/INRIA were also influential in spreading adoption of the Internet in France, eventually witnessing the success of the datagram-based Internet, and the demise of the X.25 andATMvirtual circuit networks.
See also
[edit]- History of the Internet
- Internet in France § History
- NPL network
- CII Mitra-15mini-computers, which ran the CYCLADES nodes
References
[edit]- Pouzin, Louis (1973)."Presentation and Major Design Aspects of the Cyclades Computer Network".Proceedings of the NATO Advanced Study Institute on Computer Communication Networks.Sussex, United Kingdom: Noordhoff International Publishing. pp. 415–434. Archived from the original on 2021-02-24.
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:CS1 maint: unfit URL (link) - Pouzin, Louis (1974)."CIGALE, the packet switching machine of the CYCLADES computer network".Proc of IFIP.Stockholm, Sweden. pp. 155–159. Archived from the original on 2021-03-01.
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:CS1 maint: unfit URL (link) - Pouzin, Louis (1975)."The CYCLADES network-present state and development trends".Symposium on Computer Networks.Gaithersburg, Maryland: IEEE Computer Society. pp. 8–13. Archived from the original on 2021-02-24.
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:CS1 maint: unfit URL (link)
Notes
[edit]- ^Abbate, Janet(2000).Inventing the Internet.MIT Press. p. 125.ISBN978-0-262-51115-5.
- ^abKim, Byung-Keun (2005).Internationalising the Internet the Co-evolution of Influence and Technology.Edward Elgar. pp. 51–55.ISBN1845426754.
- ^abBennett, Richard (September 2009)."Designed for Change: End-to-End Arguments, Internet Innovation, and the Net Neutrality Debate"(PDF).Information Technology and Innovation Foundation. p. 11.Retrieved11 September2017.
- ^abcPelkey, James. "6.3 CYCLADES Network and Louis Pouzin 1971-1972".Entrepreneurial Capitalism and Innovation: A History of Computer Communications 1968-1988.Archived fromthe originalon 2021-06-17.Retrieved2012-08-25.
- ^abPelkey, James. "6.4 Transmission Control Protocol (TCP) 1973-1976".Entrepreneurial Capitalism and Innovation: A History of Computer Communications 1968-1988.Archived fromthe originalon 2018-03-06.Retrieved2017-09-12.
- ^"The internet's fifth man".Economist.13 December 2013.Retrieved11 September2017.
In the early 1970s Mr Pouzin created an innovative data network that linked locations in France, Italy and Britain. Its simplicity and efficiency pointed the way to a network that could connect not just dozens of machines, but millions of them. It captured the imagination of Dr Cerf and Dr Kahn, who included aspects of its design in the protocols that now power the internet.
- ^"Say Bonjour to the Internet's Long-Lost French Uncle".Wired.3 January 2013.Retrieved11 September2017.
- ^abRussell, Andrew L.; Schafer, Valérie (2014)."In the Shadow of ARPANET and Internet: Louis Pouzin and the Cyclades Network in the 1970s".Technology and Culture.55(4): 880–907.ISSN0040-165X.
- ^Andrew L. Russell (30 July 2013)."OSI: The Internet That Wasn't".IEEE Spectrum.Vol. 50, no. 8.
- ^Pouzin, Louis (1973)."Presentation and major design aspects of the CYCLADES computer network".ACM Press: 80–87.doi:10.1145/800280.811034.
{{cite journal}}
:Cite journal requires|journal=
(help) - ^McKenzie, Alexander (2011). "INWG and the Conception of the Internet: An Eyewitness Account".IEEE Annals of the History of Computing.33(1): 66–71.doi:10.1109/MAHC.2011.9.ISSN1934-1547.S2CID206443072.
- ^A Proposal for Interconnecting Packet Switching Networks,L. Pouzin, Proceedings of EUROCOMP, Brunel University, May 1974, pp. 1023-36.
- ^"A Technical History of CYCLADES"Archived2013-09-01 at theWayback Machine,Technical Histories of the Internet & other Network Protocols (THINK), University of Texas, 11 June 2002
- ^Gillies, James and Robert Cailliau (2000).How the Web Was Born: The Story of the World Wide Web.Oxford University Press. p.38.ISBN978-0-19-286207-5.
- ^"The path to digital literacy and network culture in France (1980s to 1990s)".The Routledge Companion to Global Internet Histories.Taylor & Francis. 2017. pp. 84–89.ISBN978-1317607656.
- ^Cerf, V.; Kahn, R. (1974)."A Protocol for Packet Network Intercommunication"(PDF).IEEE Transactions on Communications.22(5): 637–648.doi:10.1109/TCOM.1974.1092259.ISSN1558-0857.
The authors wish to thank a number of colleagues for helpful comments during early discussions of international network protocols, especially R. Metcalfe, R. Scantlebury, D. Walden, and H. Zimmerman; D. Davies and L. Pouzin who constructively commented on the fragmentation and accounting issues; and S. Crocker who commented on the creation and destruction of associations.
- ^Abbate, Janet (2000).Inventing the Internet.MIT Press. p. 127.ISBN978-0-262-51115-5.
Further reading
[edit]- Louis Pouzin (editor),The Cyclades Computer Network: Toward Layered Network Architectures(North-Holland, Amsterdam, 1982)
- Russell, Andrew L.; Schafer, Valérie (2014)."In the Shadow of ARPANET and Internet: Louis Pouzin and the Cyclades Network in the 1970s".Technology and Culture.55(4): 880–907.doi:10.1353/tech.2014.0096.ISSN1097-3729.S2CID143582561.
- Paloque-Bergès, Camille; Schafer, Valérie (2019-01-02)."French memories about the ARPANET: a conversation with Michel Élie and Gérard Le Lann".Internet Histories.3(1): 81–97.doi:10.1080/24701475.2018.1536934.ISSN2470-1475.S2CID150309933.