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107-670: It was designed in 1983 by Donald Davies and David Clayden at the National Physical Laboratory (United Kingdom) in response to a request of the UK Bankers Automated Clearing Services. The MAA was one of the first Message Authentication Code algorithms to gain widespread acceptance. The original specification of the MAA was given in a combination of natural language and tables, complemented by two implementations in C and BASIC programming languages. The MAA

214-469: A cholera epidemic; according to a by-law , any house within 100 feet (30 m) of a sewer had to be connected to it. By 1871 the population had risen to 100,000, and the national census listed Portsmouth's population as 113,569. A working-class suburb was constructed in the 1870s, when about 1,820 houses were built, and it became Somerstown . Despite public-health improvements, 514 people died in an 1872 smallpox epidemic. On 21 December of that year,

321-592: A fort , at nearby Portchester in the late third century. The city's Old English Anglo-Saxon name, " Portesmuða ", is derived from port (a haven) and muða (the mouth of a large river or estuary). In the Anglo-Saxon Chronicle , a warrior named Port and his two sons killed a noble Briton in Portsmouth in 501. Winston Churchill , in A History of the English-Speaking Peoples , wrote that Port

428-513: A "single network" for data and telephone communications. Davies proposed and studied a commercial national data network in the United Kingdom and designed and built the first implementation of packet switching in the local-area NPL network in 1966-69 to demonstrate the technology. Many of the wide-area packet-switched networks built in the late 1960s and 1970s were similar "in nearly all respects" to his original 1965 design. Davies' work influenced

535-599: A "single network" for data and telephone communications: Computer developments in the distant future might result in one type of network being able to carry speech and digital messages efficiently. Davies and his team were the first to write communication protocols in a modern data-commutation context in an April 1967 memorandum A Protocol for Use in the NPL Data Communications Network written by Roger Scantlebury and Keith Bartlett. His work on packet switching, presented by Scantlebury, initially caught

642-457: A conclusive and decisive victory. Portsmouth Harbour was a vital military embarkation point for the 6 June 1944 D-Day landings. Southwick House , just north of the city, was the headquarters of Supreme Allied Commander Dwight D. Eisenhower . A V-1 flying bomb hit Newcomen Road on 15 July 1944, killing 15 people. Much of the city's housing stock was damaged during the war. The wreckage was cleared in an attempt to improve housing quality after

749-483: A contemporary working on analysing message delays using queueing theory , developed a mathematical model for the operation of message switching networks in his PhD thesis during 1961-2, published as a book in 1964. However, Kleinrock's later claim to have developed the theoretical basis of packet switching networks is disputed by other Internet pioneers , including by Robert Taylor , Baran and Davies. Donald Davies and Paul Baran are recognized by historians and

856-710: A diplomatic incident with the Soviet Union and scandal in British domestic politics. On 2 April 1982, Argentine forces invaded two British territories in the South Atlantic: the Falkland Islands and South Georgia and the South Sandwich Islands . The British government's response was to dispatch a naval task force , and the aircraft carriers HMS  Hermes and HMS  Invincible sailed from Portsmouth for

963-578: A figure which increased to 23,000 during the First World War . The whole of Portsea Island came united under the control of Portsmouth borough council in 1904. In 1906, HMS  Dreadnought was launched from Portsmouth Dockyard. The ship revolutionised naval warfare and began an arms race with Germany. The ship's entry into service in 1906 represented such an advance in naval technology that her name came to be associated with an entire generation of battleships. A major terrorist incident occurred in

1070-462: A fleet of 100 ships to the port. Richard gave Portsmouth market-town status with a royal charter on 2 May, authorising an annual fifteen-day free-market fair, weekly markets and a local court to deal with minor matters, and exempted its inhabitants from an £18 annual tax. The 1194 royal charter's 800th anniversary was celebrated in 1994 with ceremonies at the city museum. King John reaffirmed Richard   I's rights and privileges, and established

1177-412: A large section of the traffic... Business use of the telephone may be reduced by the growth of the kind of service we contemplate. Davies proposed dividing computer messages into very "short messages in fixed format" that are routed independently across a network, with differing routes allowed for related packets, which are reassembled at the destination. Davies used the word "packet" after consulting with

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1284-641: A linguist because it was capable of being translated into languages other than English without compromise. The following year, he returned to work at the NPL, where he became Superintendent of the Computer Science Division and transformed its computing activity. He designed and proposed a commercial national data network based on packet switching in his 1966 Proposal for the Development of a National Communications Service for On-line Data Processing . This work

1391-537: A number of French ships blockaded the town (which housed ships which were set to invade Normandy); Henry gathered a fleet at Southampton, and invaded the Norman coast in August that year. Recognising the town's growing importance, he ordered a wooden Round Tower to be built at the mouth of the harbour; it was completed in 1426. Henry VII rebuilt the fortifications with stone, assisted Robert Brygandine and Sir Reginald Bray in

1498-525: A number of patents, including methods for providing secure communication to enable the use of smart cards . He retired from NPL in 1984, becoming a leading consultant on data security to the banking industry and publishing a book on the topic that year. Together with David O. Clayden, he designed the Message Authenticator Algorithm (MAA) in 1983, one of the first message authentication code algorithms to gain widespread acceptance. It

1605-738: A permanent naval base. The first docks were begun by William of Wrotham in 1212, and John summoned his earls, barons, and military advisers to plan an invasion of Normandy . In 1229, declaring war against France, Henry   III assembled a force described by historian Lake Allen as "one of the finest armies that had ever been raised in England". The invasion stalled, and returned from France in October 1231. Henry   III summoned troops to invade Guienne in 1242, and Edward   I sent supplies for his army in France in 1295. Commercial interests had grown by

1712-758: A prominent case study for assessing various formal methods . The MAA has been used as a prominent case study for assessing various formal methods . In the early 1990s, the NPL developed three formal specifications of the MAA: one in Z , one in LOTOS , and one in VDM . The VDM specification became part of the 1992 revision of the International Standard 8731-2, and three implementations were manually derived from that latter specification: C , Miranda , and Modula-2 . Other formal models of

1819-554: A slow destinations), he assumed that "all users of the network will provide themselves with some kind of error control", thus inventing what came to be known as the end-to-end principle . In Scantlebury's report following the conference, he noted "It would appear that the ideas in the NPL paper at the moment are more advanced than any proposed in the USA". Larry Roberts , of the Advanced Research Projects Agency (ARPA) of

1926-859: Is among the few British cities with two cathedrals: the Anglican Cathedral of St Thomas and the Roman Catholic Cathedral of St John the Evangelist . The waterfront and Portsmouth Harbour are dominated by the Spinnaker Tower , one of the United Kingdom's tallest structures at 560 feet (170 m). Southsea is Portsmouth's seaside resort , which was named after Southsea Castle. Southsea has two piers; Clarence Pier amusement park and South Parade Pier . The world's only regular hovercraft service operates from Southsea Hoverport to Ryde on

2033-509: Is east of the island. The Farlington Marshes , in the north off the coast of Farlington , is a 125 hectares (310 acres) grazing marsh and saline lagoon. One of the oldest local reserves in the county, built from reclaimed land in 1771, it provides a habitat for migratory wildfowl and waders . South of Portsmouth are Spithead , the Solent , and the Isle of Wight . Its southern coast was fortified by

2140-421: Is located on Portsea Island , off the south coast of England in the Solent , making Portsmouth the only city in England not located primarily on the mainland . The city is located 22 miles (35 km) south-east of Southampton , 50 miles (80 km) west of Brighton and Hove and 74 miles (119 km) south-west of London . With a population last recorded at 208,100, it is the most densely-populated city in

2247-553: Is located primarily on Portsea Island and is the United Kingdom's only island city, although the city has expanded to the mainland. Gosport is a town and borough to the west. Portsea Island is separated from the mainland by Portsbridge Creek , which is crossed by three road bridges (the M275 motorway , the A3 road , and the A2030 road ), a railway bridge, and two footbridges. Portsea Island, part of

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2354-429: Is necessary because of different network packet size limits, Cerf and Kahn maintain that the only logical place to locate the reconstruction process is in the destination host (this is because the last network entered may have the least packet size limit, so that the last gateway has to fragment packets). This philosophy goes against the widely held view that packet networks should deliver a data stream exactly equivalent to

2461-519: Is the high reliability and availability of the services. They cannot become an integral part of industry and commerce unless they can be utterly reliable in the way we have come to expect of the traditional telecommunication media. A third requirement is an overall system design which allows for adaptability to changes in the system as well as to new user requirements. Davies, along with Derek Barber, his deputy, and Roger Scantlebury, conducted research into protocols for internetworking . They participated in

2568-475: Is the residential Milton and an area of reclaimed land known as Milton Common (formerly Milton Lake), a "flat scrubby land with a series of freshwater lakes". Further north on the east coast is Baffins , with the Great Salterns recreation ground and golf course around Portsmouth College . The Hilsea Lines are a series of defunct fortifications on the island's north coast, bordering Portsbridge Creek and

2675-551: Is the second busiest in the United Kingdom after Dover , handling around three million passengers a year. The city formerly had its own airport, Portsmouth Airport , until its closure in 1973. The University of Portsmouth enrolls 23,000 students. Portsmouth is the birthplace of notable people such as author Charles Dickens , engineer Isambard Kingdom Brunel , former Prime Minister James Callaghan , actor Peter Sellers and author-journalist Christopher Hitchens . The Romans built Portus Adurni (now called Portchester Castle ),

2782-531: The Challenger expedition embarked on a 68,890-nautical-mile (127,580 km) circumnavigation of the globe for scientific research. When the British Empire was at its height of power, covering a quarter of Earth's total land area and 458 million people at the turn of the 20th century, Portsmouth was considered "the world's greatest naval port". In 1900, Portsmouth Dockyard employed 8,000 people   –

2889-684: The ARPANET in the United States and the CYCLADES project in France, and was key to the development of the data communications technology used in Internet , which is a network of networks. Davies' work was independent of the work of Paul Baran in the United States who had some similar ideas in the early 1960s, and who also provided input to the ARPANET project, after his work was highlighted by Davies' team. Davies

2996-623: The Battle of Trafalgar in 2005, with Queen Elizabeth II present at a fleet review and a mock battle. The naval base is home to two-thirds of Britain's surface fleet. The city also hosted international commemorations for 50th, 75th and 80th anniversaries of the D-Day landings, these were attended by international leaders and remaining veterans. Portsmouth is 73.5 miles (118.3 km) by road from central London, 49.5 miles (79.7 km) west of Brighton , and 22.3 miles (35.9 km) east of Southampton . It

3103-679: The Battle of Trafalgar . The Royal Navy's reliance on Portsmouth led to its becoming the most fortified city in the world. The Royal Navy's West Africa Squadron , tasked with halting the slave trade, began operating out of Portsmouth in 1808. A network of forts, known as the Palmerston Forts , was built around the town as part of a programme led by Prime Minister Lord Palmerston to defend British military bases from an inland attack following an Anglo-French war scare in 1859. The forts were nicknamed "Palmerston's Follies" because their armaments were pointed inland and not out to sea. In April 1811,

3210-678: The Dissolution of the Monasteries , in 1539 in anticipation of a French invasion. He also invested heavily in the town's dockyard, expanding it to 8 acres (3.2 ha). Around this time, a Tudor defensive boom stretched from the Round Tower to Fort Blockhouse in Gosport to protect Portsmouth Harbour. From Southsea Castle, Henry witnessed his flagship Mary Rose sink in action against the French fleet in

3317-483: The Eocene . Northern areas of the city include Stamshaw , Hilsea and Copnor , Cosham , Drayton , Farlington , Paulsgrove and Port Solent . Other districts include North End and Fratton. The west of the city contains council estates , such as Buckland , Landport , and Portsea, which replaced Victorian terraces destroyed by Second World War bombing. After the war, the 2,000-acre (810 ha) Leigh Park estate

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3424-548: The Hampshire Basin , is low-lying; most of the island is less than 3 metres (9.8 ft) above sea level . The island's highest natural elevation is the Kingston Cross road junction, at 21 feet (6.4 m) above ordinary spring tide. Old Portsmouth , the original town, is in the south-west part of the island and includes Portsmouth Point (nicknamed Spice Island). The main channel entering Portsmouth Harbour, west of

3531-566: The International Network Working Group from 1972, initially chaired by Vint Cerf and later by Barber. Davies and Scantlebury were acknowledged by Cerf and Bob Kahn in their seminal 1974 paper on internetworking, A Protocol for Packet Network Intercommunication . Davies and Barber published Communication networks for computers in 1973. They spoke at the Data Communications Symposium in 1975 about

3638-405: The Isle of Wight . Southsea Common is a large open-air public recreation space which serves as a venue for a wide variety of annual events. The city has several mainline railway stations that connect to London Victoria and London Waterloo amongst other lines in southern England. Portsmouth International Port is a commercial cruise ship and ferry port for international destinations. The port

3745-652: The National Museum of the Royal Navy and Portsmouth Historic Dockyard ; which has a collection of historic warships, including the Mary Rose , Lord Nelson 's flagship, HMS  Victory (the world's oldest naval ship still in commission), and HMS  Warrior , the Royal Navy's first ironclad warship . The former HMS  Vernon shore establishment has been redeveloped into a large retail outlet destination known as Gunwharf Quays which opened in 2001. Portsmouth

3852-577: The Round Tower , the Square Tower , Southsea Castle, Lumps Fort and Fort Cumberland . Four sea forts were built in the Solent by Lord Palmerston : Spitbank Fort , St Helens Fort , Horse Sand Fort and No Man's Land Fort . The resort of Southsea is on the central southern shoreline of Portsea Island, and Eastney is east. Eastney Lake covered nearly 170 acres (69 hectares) in 1626. North of Eastney

3959-534: The United Kingdom . Portsmouth forms part of the South Hampshire urban area with Gosport , Fareham , Havant , Eastleigh and Southampton. Portsmouth's history can be traced to Roman times and has been a significant Royal Navy dockyard and base for centuries. Portsmouth was founded c.  1180 by Anglo-Norman merchant Jean de Gisors in the south-west area of Portsea Island, a location now known as Old Portsmouth . Around this time, de Gisors ordered

4066-740: The United States Department of Defense (DoD), applied Davies' concepts of packet switching for the ARPANET, which went on to become a predecessor to the Internet . In July 1968, NPL put on a demonstration of real and simulated networks at an event organised by the Real Time Club at the Royal Festival Hall in London. Davies first presented his own ideas on packet switching at a conference in Edinburgh on 5 August 1968. In 1969, Davies

4173-461: The transfer of Hong Kong in 1997, after which Britannia was retired from royal service, decommissioned and relocated to Leith as a museum ship. HMNB Portsmouth is an operational Royal Navy base and is home to two-thirds of the UK's surface fleet. The base has long been nicknamed Pompey , a nickname it shares with the wider city of Portsmouth and Portsmouth Football Club . The naval base also contains

4280-501: The "battle for access standards" between datagrams and virtual circuits , with Barber saying the "lack of standard access interfaces for emerging public packet-switched communication networks is creating 'some kind of monster' for users". Internetworking experiments at NPL under Davies included connecting with the European Informatics Network (EIN) by translating between two different host protocols and connecting with

4387-552: The 1545 Battle of the Solent with the loss of about 500 lives. Some historians believe that the Mary Rose turned too quickly and submerged her open gun ports; according to others, it sank due to poor design. Portsmouth's fortifications were improved by successive monarchs. The town experienced an outbreak of plague in 1563, which killed about 300 of its 2,000 inhabitants. In 1623, Charles I (then Prince of Wales) returned to Portsmouth from France and Spain. His unpopular military adviser, George Villiers, 1st Duke of Buckingham ,

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4494-469: The 1960s and early 1970s. The success of the project and the quality of its housing are debatable. Portsmouth was affected by the decline of the British Empire in the second half of the 20th century. Shipbuilding jobs fell from 46 per cent of the workforce in 1951 to 14 per cent in 1966, drastically reducing manpower in the dockyard. The city council attempted to create new work; an industrial estate

4601-651: The 20th century, Portsmouth achieved city status on 21 April 1926. During the Second World War , the city was a pivotal embarkation point for the D-Day landings and was bombed extensively in the Portsmouth Blitz , which resulted in the deaths of 930 people. In 1982, a large Royal Navy task force departed from Portsmouth for the Falklands War . Her Majesty's Yacht Britannia was formerly based in Portsmouth and oversaw

4708-576: The British computer industry. In 1965, Davies became interested in data communications following a seminar he gave at the Massachusetts Institute of Technology . He saw that a significant problem with the new time-sharing computer systems was the cost of keeping a phone connection open for each user. Davies' key insight came in the realisation that computer network traffic was inherently "bursty" in nature with periods of silence, compared with relatively constant telephone traffic. He applied

4815-505: The Danes at Portsmouth, where most of their ships were docked. Although the Danes were driven off, Wulfherd was killed. The Danes returned in 1001 and pillaged Portsmouth and the surrounding area, threatening the English with extinction. They were massacred by the English survivors the following year; rebuilding began, although the town experienced further attacks until 1066 . Although Portsmouth

4922-565: The French landed in Portsmouth. Although the town was plundered and burnt, its inhabitants drove the French off to raid towns in the West Country . Henry V gathered his forces in Portsmouth for an invasion of France in 1415, it was while staying at Portchester Castle that the Southampton plot was uncovered. This campaign would culminate with victory at the battle of Agincourt. He also built Portsmouth's first permanent fortifications . In 1416,

5029-520: The Greyhound public house on High Street, which is now Buckingham House and has a commemorative plaque. Most residents (including the mayor) supported the parliamentarians during the English Civil War , although military governor Colonel Goring supported the royalists . The town, a base of the parliamentarian navy, was blockaded from the sea. Parliamentarian troops were sent to besiege it , and

5136-613: The Internet" at The National Museum of Computing . A blue plaque commemorating Davies was unveiled in Treorchy in July 2013. Davies was survived by his wife Diane, a daughter, two sons and four grandchildren. Portsmouth Portsmouth ( / ˈ p ɔːr t s m ə θ / PORTS -məth ) is a port city and unitary authority in Hampshire , England. Most of Portsmouth

5243-443: The MAA have been developed. In 2017, a complete formal specification of the MAA as a large term rewriting system was published; From this specification, implementations of the MAA in fifteen different languages have been generated automatically. In 2018, two new formal specifications of the MAA, in LOTOS and LNT, have been published. Donald Davies Donald Watts Davies , CBE FRS (7 June 1924 – 28 May 2000)

5350-590: The Portsea Island Company constructed the first piped-water supply to upper- and middle-class houses. It supplied water to about 4,500 of Portsmouth's 14,000 houses, generating an income of £5,000 a year. HMS Victory ' s active career ended in 1812, when she was moored in Portsmouth Harbour and used as a depot ship . The town of Gosport contributed £75 a year to the ship's maintenance. In 1818, John Pounds began teaching working-class children in

5457-539: The Post Office Experimental Packet Switched Service (EPSS) using a common host protocol in both networks. Their research confirmed establishing a common host protocol would be more reliable and efficient than translating between different host protocols using a gateway. Davies published Computer networks and their protocols in 1979, in which he notes: The problems of routing in interconnected networks have received limited attention in

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5564-538: The Restoration , Charles   II married Catherine of Braganza at the Royal Garrison Church on 14 May 1662. Catherine was reputed to have introduced the cultural practice of tea drinking to England at this event. During the late 17th century, Portsmouth continued to grow; a new wharf was constructed in 1663 for military use, and a mast pond was dug in 1665. In 1684, a list of ships docked in Portsmouth

5671-494: The South Atlantic on 5 April. The successful outcome of the war reaffirmed Portsmouth's significance as a naval port and its importance to the defence of British interests. In January 1997, Her Majesty's Yacht Britannia embarked from the city on her final voyage to oversee the handover of Hong Kong; for many, this marked the end of the empire. She was decommissioned on 11 December of that year at Portsmouth Naval Base in

5778-450: The Soviet cruiser Ordzhonikidze docked in Portsmouth harbour on a diplomatic mission that had taken head of state Nikita Khrushchev and Nikolai Bulganin to Britain. Naval intelligence was interested in the design of the ship and MI6 recruited diver Lionel Crabb to collect intelligence on the ship particularly its propulsion. After diving into the harbour Crabb was never seen again. This led to

5885-428: The U.S. National Inventors Hall of Fame for independently inventing the concept of digital packet switching used in modern computer networking including the Internet. Larry Roberts said the computer networks built in the 1970s were similar "in nearly all respects" to Davies' original 1965 design. Davies' work on data communications and computer network design has been described as the "cornerstone" technology used in

5992-454: The UK" by the BBC, was demolished in late 2004 after years of debate over the expense of demolition and whether it was worth preserving as an example of 1960s brutalist architecture . Designed by Owen Luder as part of a project to "revitalise" Portsmouth in the 1960s, it consisted of a shopping centre, market, nightclubs, and a multistorey car park . Portsmouth celebrated the 200th anniversary of

6099-446: The area continued until 1974. Builders still occasionally find unexploded bombs , such as on the site of the destroyed Hippodrome Theatre in 1984. Despite efforts by the city council to build new housing, a 1955 survey indicated that 7,000 houses in Portsmouth were unfit for human habitation. A controversial decision was made to replace a section of the central city, including Landport, Somerstown and Buckland, with council housing during

6206-487: The attention of the developers of the ARPANET , a U.S. Department of Defense (DoD) network, at the Symposium on Operating Systems Principles in October 1967. The proposed network design was based on a hierarchical structure, with "local networks" communicating with a "high level network". To deal with packet permutations (due to dynamically updated route preferences) and datagram losses (unavoidable when fast sources send to

6313-503: The city in 1913, which led to the deaths of two men. During the suffragette bombing and arson campaign of 1912–1914, militant suffragettes of the Women's Social and Political Union carried out a series of politically motivated bombing and arson attacks nationwide as part of their campaign for women's suffrage . In one of the more serious suffragette attacks, a fire was purposely started at Portsmouth dockyard on 20 December 1913, in which two sailors were killed after it spread through

6420-412: The city in 1968, and IBM relocated their European headquarters in 1979. Portsmouth's population had dropped from about 200,000 to 177,142 by the end of the 1960s. Defence Secretary John Nott decided in the early 1980s that of the four home dockyards, Portsmouth and Chatham would be closed. The city council won a concession, however, and the dockyard was downgraded instead to a naval base. In 1956,

6527-543: The city's maritime connections: the lions and unicorn have fish tails, and a naval crown and a representation of the Tudor defensive boom which stretched across Portsmouth Harbour are around the unicorn. During the Second World War , the city (particularly the port) was bombed extensively by the Luftwaffe in the Portsmouth Blitz. Portsmouth experienced 67 air raids between July 1940 and May 1944, which destroyed 6,625 houses and severely damaged 6,549. The air raids caused 930 deaths and wounded almost 3,000 people, many in

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6634-448: The concept of packet switching and Davies and his team referenced Baran's earlier published work. Baran was happy to acknowledge that Davies had come up with the same idea as him independently. In an email to Davies, he wrote: You and I share a common view of what packet switching is all about, since you and I independently came up with the same ingredients. ... and [you were] the first to reduce it to practice. Leonard Kleinrock ,

6741-473: The construction of a chapel dedicated to St Thomas Becket . This became a parish church by the 14th century. Portsmouth was established as a town with a royal charter on 2 May 1194. The city is home to the first drydock ever built. It was constructed by Henry VII in 1496. Portsmouth has the world's oldest dry dock , "The Great Stone Dock" ; originally built in 1698, rebuilt in 1769 and presently known as "No.5 Dock". The world's first mass production line

6848-414: The construction of the world's first dry dock , and raised the Square Tower in 1494. He made Portsmouth a Royal Dockyard, England's only dockyard considered "national". Although King Alfred may have used Portsmouth to build ships as early as the ninth century, the first warship recorded as constructed in the town was the Sweepstake (built in 1497). Henry VIII built Southsea Castle, financed by

6955-453: The country's first ragged school . The Portsea Improvement Commissioners installed gas street lighting throughout Portsmouth in 1820, followed by Old Portsmouth three years later. During the 19th century, Portsmouth expanded across Portsea Island. Buckland was merged into the town by the 1860s, and Fratton and Stamshaw were incorporated by the next decade. Between 1865 and 1870, the council built sewers after more than 800 people died in

7062-467: The development of the Internet , which is a global system of connected computer networks (a network of networks). Davies was appointed a Distinguished Fellow of the British Computer Society (BCS) in 1975 and was made a CBE in 1983, and later a Fellow of the Royal Society in 1987. He received the John Player Award from the BCS in 1974. and was awarded a medal by the John von Neumann Computer Society in Hungary in 1985. In 2000, Davies shared

7169-427: The dockyard and military establishments. On the night of the city's heaviest raid (10 January 1941), the Luftwaffe dropped 140 tonnes of high-explosive bombs which killed 171 people and left 3,000 homeless. Many of the city's houses were damaged, and areas of Landport and Old Portsmouth destroyed; the future site of Gunwharf Quays was razed to the ground. The Guildhall was hit by an incendiary bomb which burnt out

7276-410: The dockyard during the war, making it one of the empire's most strategic ports at the time. Portsmouth's boundaries were extended onto the mainland of Great Britain between 1920 and 1932 by incorporating Paulsgrove , Wymering , Cosham , Drayton and Farlington into Portsmouth. Portsmouth was granted city status in 1926 after a long campaign by the borough council. The application was made on

7383-449: The early 19th century as "azure a crescent or, surmounted by an estoile of eight points of the last." Its design is apparently based on 18th-century mayoral seals. A connection of the coat of arms with the Great Seal of Richard I (which had a separate star and crescent) dates to the 20th century. Marc Isambard Brunel established the world's first mass-production line at Portsmouth Block Mills , making pulley blocks for rigging on

7490-404: The flames. The two victims were a pensioner and a signalman. The attack was notable enough to be reported on in the press in the United States , with the New York Times reporting on the disaster two days after with the headline "Big Portsmouth Fire Loss". The report also disclosed that at a previous police raid on a suffragette headquarters, "papers were discovered disclosing a plan to fire

7597-402: The following century, and its exports included wool, corn, grain, and livestock. Edward II ordered all ports on the south coast to assemble their largest vessels at Portsmouth to carry soldiers and horses to the Duchy of Aquitaine in 1324 to strengthen defences. A French fleet commanded by David II of Scotland attacked in the English Channel , ransacked the Isle of Wight and threatened

7704-640: The globe. The 11-ship First Fleet left on 13 May 1787 to establish the first European colony in Australia , the beginning of prisoner transportation; Captain William Bligh of HMS  Bounty also sailed from the harbour that year. After the 28 April 1789 mutiny on the Bounty , HMS  Pandora was dispatched from Portsmouth to bring the mutineers back for trial. The court-martial opened on 12 September 1792 aboard HMS  Duke in Portsmouth Harbour; of

7811-469: The grounds that it was the "first naval port of the kingdom". In 1929, the city council added the motto "Heaven's Light Our Guide" to the medieval coat of arms. Except for the celestial objects in the arms, the motto was that of the Star of India and referred to the troopships bound for British India which left from the port. The crest and supporters are based on those of the royal arms , but altered to show

7918-581: The guns of Southsea Castle were fired at the town's royalist garrison. Parliamentarians in Gosport joined the assault, damaging St Thomas's Church . On 5 September 1642, the remaining royalists in the garrison at the Square Tower were forced to surrender after Goring threatened to blow it up; he and his garrison were allowed safe passage out of the city. Under the Commonwealth of England , Robert Blake used

8025-597: The harbour as his base during the First Anglo-Dutch War in 1652 and the Anglo-Spanish War . He died within sight of the town, returning from Cádiz . After the end of the Civil War , Portsmouth was among the first towns to declare Charles   II king and began to prosper. The first ship built in over 100 years, HMS  Portsmouth , was launched in 1650; twelve ships were built between 1650 and 1660. After

8132-454: The harbour; navigational charts use the contraction. According to one historian, the name may have been brought back from a group of Portsmouth-based sailors who visited Pompey's Pillar in Alexandria , Egypt, around 1781. Another theory is that it is named after the harbour's guardship, Pompee , a 74-gun French ship of the line captured in 1793. Portsmouth's coat of arms is attested in

8239-599: The inaugural IEEE Internet Award . In 2007, he was inducted into the National Inventors Hall of Fame , and in 2012 Davies was inducted into the Internet Hall of Fame by the Internet Society . Davies received a lifetime achievement award in 2001 for his research into secure communications for smart cards. NPL sponsors a gallery, opened in 2009, about the development of packet switching and "Technology of

8346-422: The industrial area. The fire spread rapidly as there were many old wooden buildings in the area, including the historic semaphore tower which dated back to the eighteenth century, which was completely destroyed. The damage to the dockyard area cost the city £200,000 in damages, equivalent to £23,600,000 today. In the midst of the firestorm, a battleship, HMS  Queen Mary , had to be towed to safety to avoid

8453-487: The interior and destroyed its inner walls, although the civic plate was retrieved unharmed from the vault under the front steps. After the raid, Portsmouth mayor Denis Daley wrote for the Evening News : We are bruised but we are not daunted, and we are still as determined as ever to stand side by side with other cities who have felt the blast of the enemy, and we shall, with them, persevere with an unflagging spirit towards

8560-454: The island, passes between Old Portsmouth and Gosport. Portsmouth Harbour has a series of lakes, including Fountain Lake (near the commercial port), Portchester Lake (south central), Paulsgrove Lake (north), Brick Kiln Lake and Tipner (east), and Bombketch and Spider Lakes (west). Further northwest, around Portchester, are Wicor, Cams, and Great Cams Lakes. The large tidal inlet of Langstone Harbour

8667-427: The literature; notable papers are those by Cerf and Kahn and, more recently, Sunshine. ... The gateway nodes must be provided with an adequate packet buffer pool to cater for the likely level of inter-network traffic. Cerf and Kahn suggest that message reassembly should not take place at gateways; this implies that packet ordering need not be maintained if adaptive routing disrupts packet order. If fragmentation of packets

8774-471: The mainland. Portsdown Hill dominates the skyline in the north, and contains several large Palmerston Forts such as Fort Fareham , Fort Wallington , Fort Nelson , Fort Southwick , Fort Widley , and Fort Purbrook . Portsdown Hill is a large band of chalk ; the rest of Portsea Island is composed of layers of London Clay and sand (part of the Bagshot Formation ), formed principally during

8881-518: The navy's ships. The first machines were installed in January 1803, and the final set (for large blocks) in March 1805. In 1808, the mills produced 130,000 blocks. By the turn of the 19th century, Portsmouth was the largest industrial site in the world; it had a workforce of 8,000, and an annual budget of £570,000. In 1805, Admiral Nelson left Portsmouth to command the fleet which defeated France and Spain at

8988-487: The nuclear weapons Tube Alloys project at Birmingham University. He then returned to Imperial taking a first class degree in mathematics (1947); he was also awarded the Lubbock memorial Prize as the outstanding mathematician of his year. In 1955, he married Diane Burton; they had a daughter and two sons. From 1947, he worked at the National Physical Laboratory (NPL) at Teddington , just outside London, where Alan Turing

9095-576: The presence of Elizabeth II , the Duke of Edinburgh , and twelve senior members of the royal family. Redevelopment of the naval shore establishment HMS  Vernon began in 2001 as a complex of retail outlets, clubs, pubs, and a shopping centre known as Gunwharf Quays. Construction of the 552-foot-tall (168 m) Spinnaker Tower , sponsored by the National Lottery , began at Gunwharf Quays in 2003. The Tricorn Centre , called "the ugliest building in

9202-411: The principle of time-sharing to the data communications line as well as the computer to invent the concept of what he called packet switching . Davies forecast today's "killer app" for his new communication service: The greatest traffic could only come if the public used this means for everyday purposes such as shopping... People sending enquiries and placing orders for goods of all kinds will make up

9309-473: The project and concentrated on delivering the less ambitious Pilot ACE computer, which first worked in May 1950. A commercial spin-off, DEUCE was manufactured by English Electric Computers and became one of the best-selling machines of the 1950s. Davies also worked on applications of traffic simulation and machine translation. In the early 1960s, he worked on government technology initiatives designed to stimulate

9416-548: The received data stream. For a long period of time, the network engineering community was polarized over the implementation of competing protocol suites, a debate commonly called the Protocol Wars . It was unclear which type of protocol would result in the best and most robust computer networks. Davies relinquished his management responsibilities in 1979 to return to research. He became particularly interested in computer network security and his research on cryptography led to

9523-650: The ten remaining men, three were sentenced to death. In 1789, a chapel was erected in Prince George's Street and was dedicated to St John by the Bishop of Winchester. Around this time, a bill was passed in the House of Commons on the creation of a canal to link Portsmouth to Chichester; however, the project was abandoned. The city's nickname, Pompey, is thought to have derived from the log entry of Portsmouth Point (contracted "Po'm.P." – Po' rts m outh P. oint) as ships entered

9630-424: The town. Edward   III instructed all maritime towns to build vessels and raise troops to rendezvous at Portsmouth. Two years later, a French fleet led by Nicholas Béhuchet raided Portsmouth and destroyed most of the town; only the stone-built church and hospital survived. After the raid, Edward   III exempted the town from national taxes to aid its reconstruction. In 1377, shortly after Edward died,

9737-555: The war; before permanent accommodations could be built, Portsmouth City Council built prefabs for those who had lost their homes. More than 700 prefab houses were constructed between 1945 and 1947, some over bomb sites. The first permanent houses were built away from the city centre, in new developments such as Paulsgrove and Leigh Park ; construction of council estates in Paulsgrove was completed in 1953. The first Leigh Park housing estates were completed in 1949, although construction in

9844-633: The world, including Louis Pouzin's CYCLADES project in France. In a 1978 special edition of the Proceedings of the IEEE on packet switching, Bob Kahn , the guest editor, quoted Davies' reflections on ten years of experience with packet communication networks: ... there are three factors, above all, which critically affect the quality of the network. The most critical factor is our ability to design man-machine interfaces which are convenient and natural for most people to use. A second factor of some importance

9951-468: The yard". On 1 October 1916, Portsmouth was bombed by a Zeppelin airship. Although the Oberste Heeresleitung (German Supreme Army Command) said that the town was "lavishly bombarded with good results", there were no reports of bombs dropped in the area. According to another source, the bombs were mistakenly dropped into the harbour rather than the dockyard. About 1,200 ships were refitted in

10058-525: Was a Welsh computer scientist and Internet pioneer who was employed at the UK National Physical Laboratory (NPL). During 1965-67 he invented modern data communications , including packet switching , high-speed routers , layered communication protocols , hierarchical computer networks and the essence of the end-to-end principle , concepts that are used today in computer networks worldwide. He envisioned, in 1966, that there would be

10165-411: Was a pirate who founded Portsmouth in 501. England's southern coast was vulnerable to Danish Viking invasions during the eighth and ninth centuries, and was conquered by Danish pirates in 787. In 838, during the reign of Æthelwulf, King of Wessex , a Danish fleet landed between Portsmouth and Southampton and plundered the region. Æthelwulf sent Wulfherd and the governor of Dorsetshire to confront

10272-565: Was adopted as international standard ISO 8731-2 in 1987. In 1987, Davies became a visiting professor at Royal Holloway and Bedford New College . Unbeknown to Davies at first, Paul Baran of the RAND Corporation in the United States had also worked on a similar concept in the early 1960s, although designed for voice communication using low-cost electronics without communication protocols. When Davies became aware of Baran's work in 1966 he acknowledged that they both had equally discovered

10379-421: Was adopted by ISO in 1987 and became part of international standards ISO 8730 and ISO 8731-2 intended to secure the authenticity and integrity of banking transactions. Later, cryptanalysis of MAA revealed various weaknesses, including feasible brute-force attacks, existence of collision clusters, and key-recovery techniques. For this reason, MAA was withdrawn from ISO standards in 2002 but continued to be used as

10486-603: Was born in Treorchy in the Rhondda Valley, Wales . His father, a clerk at a coalmine, died a few months later, and his mother took Donald and his twin sister back to her home town of Portsmouth , where he went to school. He attended the Southern Grammar School for Boys . He received a BSc degree in physics (1943) at Imperial College London , and then joined the war effort working as an assistant to Klaus Fuchs on

10593-455: Was built in Fratton in 1948, and others were built at Paulsgrove and Farlington during the 1950s and 1960s. Although traditional industries such as brewing and corset manufacturing disappeared during this time, electrical engineering became a major employer. Despite the cutbacks in traditional sectors, Portsmouth remained attractive to industry. Zurich Insurance Group moved their UK headquarters to

10700-552: Was designing the Automatic Computing Engine (ACE) computer. It is said that Davies spotted mistakes in Turing's seminal 1936 paper On Computable Numbers , much to Turing's annoyance. These were perhaps some of the first "programming" bugs in existence, even if they were for a theoretical computer, the universal Turing machine . The ACE project was overambitious and floundered, leading to Turing's departure. Davies took over

10807-546: Was established at the naval base's Block Mills which produced pulley blocks for the Royal Navy fleet. By the early-19th century, Portsmouth was the most heavily fortified city in the world, and was considered "the world's greatest naval port" at the height of the British Empire throughout Pax Britannica . By 1859, a ring of defensive land and sea forts, known as the Palmerston Forts , had been built around Portsmouth in anticipation of an invasion from continental Europe. In

10914-682: Was evidence of its increasing national importance. Between 1667 and 1685, the town's fortifications were rebuilt; new walls were constructed with bastions and two moats were dug, making Portsmouth one of the world's most heavily fortified places. In 1759, General James Wolfe sailed to capture Quebec ; the expedition, although successful, cost him his life. His body was brought back to Portsmouth in November, and received high naval and military honours. Two years later, on 30 May 1775, Captain James Cook arrived on HMS  Endeavour after circumnavigating

11021-420: Was invited to Japan to lecture on packet switching. He gave a series of nine three-hour lectures, concluding with an intense discussion with around 80 people. During 1968-9, Davies directed the construction of the network, elements of which went live in early 1969, the first implementation of packet switching in the world. The local-area Mark I NPL network , became fully operational in January 1970. It

11128-627: Was not mentioned in the 1086 Domesday Book , Bocheland ( Buckland ), Copenore ( Copnor ), and Frodentone ( Fratton ) were. According to some sources, it was founded in 1180 by the Anglo-Norman merchant Jean de Gisors . King Henry II died in 1189; his son, Richard I (who had spent most of his life in France), arrived in Portsmouth en route to his coronation in London. When Richard returned from captivity in Austria in May 1194, he summoned an army and

11235-412: Was stabbed to death in an Old Portsmouth pub by war veteran John Felton five years later. Felton never attempted to escape, and was caught walking the streets when soldiers confronted him; he said, "I know that he is dead, for I had the force of forty men when I struck the blow". Felton was hanged, and his body chained to a gibbet on Southsea Common as a warning to others. The murder took place in

11342-477: Was the first to describe the concept of high-speed "switching nodes", today known as routers as well as "interface computers". Davies applied queueing theory to show that "there is an ample margin between the estimated performance of the [packet-switched] system and the stated requirement" in terms of a satisfactory response time for a human user. This addressed a key question about the viability of computer networking. In this paper, he predicted there would be

11449-567: Was upgraded to the Mark II in 1973 with a layered protocol architecture, and remained in operation until 1986. The NPL team also carried out simulation work on packet networks, studying datagrams and network congestion in wide-area networks of a scale to facilitate data communications across the United Kingdom. These early years of computer resource sharing were documented in the 1972 film Computer Networks: The Heralds of Resource Sharing . Davies' original ideas influenced other research around

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