The National Physical Laboratory (NPL) is the national measurement standards laboratory of the United Kingdom. It sets and maintains physical standards for British industry.
Founded in 1900, the NPL is one of the oldest metrology institutes in the world. Research and development work at the laboratory has contributed to the advancement of many disciplines of science, including the development of early computers in the late 1940s and 1950s, construction of the first accurate atomic clock in 1955, and the invention and first implementation of packet switching in the 1960s, which is today one of the fundamental technologies of the Internet.[2][3][4] The former heads of NPL include many individuals who were pillars of the British scientific establishment.[5][6]
In the 19th century, the Kew Observatory was run by self-funded devotees of science. In the early 1850s, the observatory began charging fees for testing meteorological instruments and other scientific equipment. As universities in the United Kingdom created and expanded physics departments, the governing committee of the observatory became increasingly dominated by paid university physicists in the last two decades of the nineteenth century. By this time, instrument-testing was the observatory's main role. Physicists sought the establishment of a state-funded scientific institution for testing electrical standards.[7]
Founding
The National Physical Laboratory was established in 1900 at Bushy House in Teddington. Its purpose was "for standardising and verifying instruments, for testing materials, and for the determination of physical constants".[8] The laboratory was run by the UK government, with members of staff being part of the civil service. It grew to fill a large selection of buildings on the Teddington site.[9]
Late 20th century
Administration of NPL was contracted out in 1995 under a Government Owned Contractor Operated (GOCO) model, via a new operating company, NPL Management Ltd. Serco won the bid and all staff transferred to their employment. Under this regime, overhead costs halved, third-party revenues grew by 16% per annum, and the number of peer-reviewed research papers published doubled.[10][11]
The new laboratory building, which had been maintained by Serco, was transferred back to the DTI in 2004 after the private sector companies involved made losses of over £100m.[12]
It was decided in 2012 to change the operating model for NPL from 2014 onwards to include academic partners and to establish a postgraduate teaching institute on site.[13] The date of the changeover was later postponed for a year.[14] The candidates for lead academic partner were the Universities of Edinburgh, Southampton, Strathclyde and Surrey[15] with an alliance of the Universities of Strathclyde and Surrey chosen as preferred partners.[16]
Funding was announced in January 2013 for a new £25m Advanced Metrology Laboratory that will be built on the footprint of an existing unused building.[17][18]
Researchers who have worked at NPL include:[20]D. W. Dye who did important work in developing the technology of quartz clocks; the inventor Sir Barnes Wallis who did early development work on the "Bouncing Bomb" used in the "Dam Busters" wartime raids;[21]H. J. Gough, one of the pioneers of research into metal fatigue, who worked at NPL for 19 years from 1914 to 1938; and Sydney Goldstein and Sir James Lighthill who worked in NPL's aerodynamics division during World War II researching boundary layer theory and supersonic aerodynamics respectively.[22]
Alan Turing, known for his work at the Government Code and Cypher School (GC&CS) at Bletchley Park during the Second World War to decipher German encrypted messages, worked at the National Physical Laboratory from 1945 to 1947.[23] He designed there the ACE (Automatic Computing Engine), which was one of the first designs for a stored-program computer. Clifford Hodge also worked there and was engaged in research on semiconductors. Others who have spent time at NPL include Robert Watson-Watt, generally considered the inventor of radar, Oswald Kubaschewski, the father of computational materials thermodynamics and the numerical analystJames Wilkinson.[24]
The first accurate atomic clock, a caesium standard based on a certain transition of the caesium-133 atom, was built by Louis Essen and Jack Parry in 1955 at NPL.[27][28] Calibration of the caesium standard atomic clock was carried out by the use of the astronomical time scale ephemeris time (ET).[29] This led to the internationally agreed definition of the latest SI second being based on atomic time.[30]
Computing
Early computers
NPL has undertaken computer research since the mid-1940s.[31] From 1945, Alan Turing led the design of the Automatic Computing Engine (ACE) computer. The ACE project was overambitious and floundered, leading to Turing's departure.[32]Donald Davies took the project over and concentrated on delivering the less ambitious Pilot ACE computer, which first worked in May 1950. Among those who worked on the project was American computer pioneer Harry Huskey. A commercial spin-off, DEUCE was manufactured by English Electric Computers and became one of the best-selling machines of the 1950s.[32]
Beginning in the mid-1960s, Donald Davies invented and pioneered the implementation of packet switching, now the dominant basis for data communications in computer networks worldwide.[33] Davies designed and proposed a national commercial data network in his 1965 Proposal for the Development of a National Communications Service for On-line Data Processing.[34] Subsequently, the NPL team, led by Roger Scantlebury, were the first to implement packet switching in the local-area NPL network in early 1969,[35][36][37][38] which operated until 1986. They carried out work to analyse and simulate the performance of a wide-area packet-switched network capable of providing data communications facilities to most of the U.K.[39] Their research and practice influenced the ARPANET in the United States, the forerunner of the Internet, and other researchers in the UK and Europe, including Louis Pouzin.[40][41][42]
NPL sponsors a gallery, opened in 2009, about the development of packet switching and "Technology of the Internet" at The National Museum of Computing.[43]
Internetworking and Email
NPL internetworking research was led by Davies, Barber and Scantlebury, who were members of the International Network Working Group (INWG).[44][45][46][47][48] Connecting heterogeneous computer networks creates a "basic dilemma" since a common host protocol would require restructuring the existing networks. NPL connected with the European Informatics Network (Barber directed the project and Scantlebury led the UK technical contribution)[49][50][51] by translating between two different host protocols; that is, using a gateway. Concurrently, the NPL connection to the Post Office Experimental Packet Switched Service used a common host protocol in both networks. NPL research confirmed establishing a common host protocol would be more reliable and efficient.[52] The EIN protocol helped to launch the proposed INWG standard.[53]Bob Kahn and Vint Cerf acknowledged Davies and Scantlebury in their 1974 paper "A Protocol for Packet Network Intercommunication".[54]
Derek Barber proposed an electronic mail protocol in 1979 in INWG 192 and implemented it on the EIN.[55] This was referenced by Jon Postel in his early work on Internet email, published in the Internet Experiment Note series.[56]
Scrapbook
Scrapbook was an information storage and retrieval system that went live in mid-1971. It included what would now be called word processing, e-mail and hypertext, anticipating many elements of the World Wide Web.[57] The project was managed by David Yates who said of it "We had a community of bright people that were interested in new things, they were good fodder for a system like Scrapbook" and "When we had more than one Scrapbook system, hyperlinks could go across the network without the user knowing what was happening".[57][58] It was decided that any commercial development of Scrapbook should be left to industry and it was licensed to Triad and then to BT who marketed it as Milepost and developed a transaction processor as an additional feature. Various implementations were marketed on DEC, IBM and ITL machines. All NPL implementations of Scrapbook were closed down in 1984.[59]
Secure communication
In the early 1990s, the NPL developed three formal specifications of the MAA: one in Z,[60] one in LOTOS,[61] and one in VDM.[62][63] The VDM specification became part of the 1992 revision of the International Standard 8731–2, and three implementations in C, Miranda, and Modula-2.[64]
Electromagnetics
A 2020 study by researchers from Queen Mary University of London and NPL successfully used microwaves to measure blood-based molecules known to be influenced by dehydration.[65]
^"About us". NPLWebsite. Archived from the original on 23 July 2020. Retrieved 24 February 2021.
^Needham, Roger M. (2002). "Donald Watts Davies, C.B.E. 7 June 1924 – 28 May 2000". Biographical Memoirs of Fellows of the Royal Society. 48: 87–96. doi:10.1098/rsbm.2002.0006. ISSN0080-4606. S2CID72835589. This was the start of 10 years of pioneering work at the NPL in packet switching. ... At that lecture he first became aware that Paul Baran, of the RAND Corporation, had proposed a similar system in the context of military communication. His report was not as detailed as Davies's design and had not been acted on.
^Scantlebury, Roger (2001). A Brief History of the NPL Network. Symposium of the Institution of Analysts & Programmers 2001. Archived from the original on 7 August 2003. Retrieved 13 June 2024. The system first went 'live' early in 1969
^John S, Quarterman; Josiah C, Hoskins (1986). "Notable computer networks". Communications of the ACM. 29 (10): 932–971. doi:10.1145/6617.6618. S2CID25341056. The first packet-switching network was implemented at the National Physical Laboratories in the United Kingdom. It was quickly followed by the ARPANET in 1969.
^Haughney Dare-Bryan, Christine (22 June 2023). Computer Freaks (Podcast). Chapter Two: In the Air. Inc. Magazine. 35:55 minutes in. Leonard Kleinrock: Donald Davies ... did make a single node packet switch before ARPA did
^Clarke, Peter (1982). Packet and circuit-switched data networks(PDF) (PhD thesis). Department of Electrical Engineering, Imperial College of Science and Technology, University of London. "As well as the packet switched network actually built at NPL for communication between their local computing facilities, some simulation experiments have been performed on larger networks. A summary of this work is reported in [69]. The work was carried out to investigate networks of a size capable of providing data communications facilities to most of the U.K. ... Experiments were then carried out using a method of flow control devised by Davies [70] called 'isarithmic' flow control. ... The simulation work carried out at NPL has, in many respects, been more realistic than most of the ARPA network theoretical studies."
^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.
^Davies, Shanks, Heart, Barker, Despres, Detwiler and Riml, "Report of Subgroup 1 on Communication System", INWG Note No. 1.
^"Smithsonian Oral and Video Histories: Vinton Cerf". National Museum of American History. Smithsonian Institution. 24 April 1990. Retrieved 23 September 2019. Roger Scantlebury was one of the major players. And Donald Davies who ran, at least he was superintendent of the information systems division or something like that. I absolutely had a lot of interaction with NPL at the time. They in fact came to the ICCC 72 and they had been coming to previous meetings of what is now called Datacomm. Its first incarnation was a long title having to do with the analysis and optimization of computer communication networks, or something like that. This started in late 1969, I think, was when the first meeting happened in Pine Hill, Georgia. I didn't go to that one, but I went to the next one that was at Stanford, I think. That's where I met Scantlebury, I believe, for the first time. Then I had a lot more interaction with him. I would come to the UK fairly regularly, partly for IFIP or INWG reasons
^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.
^Barber, D., and J. Laws, "A Basic Mail Scheme for EIN," INWG 192, February 1979.
^ abWard, Mark (5 February 2010), Alan Turing and the Ace computer, BBC News, archived from the original on 10 October 2021, retrieved 17 February 2021 "it is certainly the first system I know of to combine screen-based word processing, hypertext and e-mail as a service over a general-purpose computer network."
^Scrapbook and the umbrella (groupware from the 70's), Retro Computing Forum, 11 February 2021, archived from the original on 10 October 2021, retrieved 18 February 2021 which cites Yates, David M. (1997), Turing's Legacy: A History of Computing at the National Physical Laboratory 1945–1995, Science Museum, ISBN978-0901805942
^Lai, M. K. F. (1991). A Formal Interpretation of the MAA Standard in Z (NPL Report DITC 184/91). Teddington, Middlesex, UK: National Physical Laboratory.
^Parkin, Graeme I.; O’Neill, G. (1990). Specification of the MAA Standard in VDM (NPL Report DITC 160/90). National Physical Laboratory, Teddington, Middlesex, UK.
^Parkin, Graeme I.; O’Neill, G. (1991). Prehn, Søren; Toetenel, W. J. (eds.). Specification of the MAA Standard in VDM. Formal Software Development – Proceedings (Volume 1) of the 4th International Symposium of VDM Europe (VDM’91), Noordwijkerhout, The Netherlands. Lecture Notes in Computer Science. Vol. 551. Springer. pp. 526–544. doi:10.1007/3-540-54834-3_31.
^Lampard, R. P. (1991). An Implementation of MAA from a VDM Specification (NPL Technical Memorandum DITC 50/91). Teddington, Middlesex, UK: National Physical Laboratory.
^Minelli, C. & Clifford, C.A. (2012). "The role of metrology and the UK National Physical Laboratory in Nanotechnology". Nanotechnology Perceptions. 8: 59–75.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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