Internet in the United Kingdom
The United Kingdom has been involved with the Internet throughout its origins and development. The telecommunications infrastructure in the United Kingdom provides Internet access to businesses and home users in various forms, including cable, DSL, wireless and mobile.

The share of households with internet access in the United Kingdom grew from 9 percent in 1998 to 93 percent in 2019. Virtually all adults aged 16 to 44 years in the UK were recent internet users (99%) in 2019, compared with 47% of adults aged 75 years and over; in aggregate, the third-highest in Europe. Online shoppers in the UK spend more per household than consumers in any other country. Internet bandwidth per Internet user was the 7th highest in the world in 2016, and average and peak internet connection speeds were top-quartile in 2017.

The Internet country code top-level domain (ccTLD) for the United Kingdom is .uk and is run by Nominet.

History 

The UK was involved in research and development of packet switching, wide area networks, and communication protocols since their origins. The development of these technologies was international from the beginning, although much of the research and development that led to the Internet was driven and funded by the United States.

Early years 
Pioneering work on computing in Britain, from the 1940s onwards, involved partnerships between academic or national bodies and industry which brought about transfer and sharing of personnel and concepts. At the National Physical Laboratory, Alan Turing worked on computer design, assisted by Donald Davies in 1947.

Packet switching 
Christopher Strachey, who became Oxford University's first professor of computation, filed a patent application for time-sharing in 1959. He passed the concept on to J. C. R. Licklider at a UNESCO-sponsored conference on Information Processing in Paris that year.

After meeting with Licklider in 1965, Donald Davies conceived the idea of packet switching for data communications. He proposed a wide area network and developed plans to implement the concept in a local area network, the NPL network, which operated from 1969 to 1986. He and his team, including Roger Scantlebury, carried out work to analyse and simulate the performance of packet switching networks, including datagram networks. Their research and practice was adopted by the ARPANET in the United States, the forerunner of the Internet, and influenced other researchers in the UK and Europe.

TCP/IP and the early Internet 
Along with researchers from the United States and France, Donald Davies, Roger Scantlebury and Derek Barber joined the International Networking Working Group (INWG) in 1972. Vint Cerf and Bob Kahn acknowledged Davies and Scantlebury in their 1974 paper "A Protocol for Packet Network Intercommunication".

Peter Kirstein's research group at University College London was one of the first international connections on the ARPANET in 1973, alongside the Norwegian Seismic Array (NORSAR) which connected via Sweden's Tanum satellite station. Kirstein co-authored (with Vint Cerf) one of the most significant early technical papers on the internetworking concept in 1978. His research group at UCL adopted TCP/IP in 1982, a year ahead of ARPANET, and played a significant role in the very earliest experimental Internet work. Kirstein's group included Sylvia Wilbur who programmed the computer used as the local node for the network.

When Jon Postel was desiging the Domain Name System in 1984, British researchers expressed a desire to use a country designator. Following the convention used in the UK academic network Name Registration Scheme, the .uk Internet country code top-level domain (ccTLD) was registered in July 1985, seven months after the original generic top-level domains such as .com and the first country code after .us. At the time, ccTLDs were delegated by Postel to a "responsible person" and Andrew McDowell at UCL managed .uk, the first country code delegation. He later passed it to Dr Willie Black at the UK Education and Research Networking Association (UK ERNA, which became JANET). The BBC registered with the DDN-NIC in 1989, establishing Internet access via Brunel University. In 1991, bbc.co.uk was registered through JANET NRS.

Black managed the “Naming Committee” until he and John Carey formed Nominet UK in 1996. As one of the first professional ccTLD operators, it became the model for many other operators worldwide.

Ivan Pope's company, NetNames, developed  the concept of a standalone commercial domain name registrar, which would sell domain registration and other associated services to the public. Network Solutions Inc. (NSI), the domain name registry for the com, net, and org top-level domains (TLDs), assimilated this model, which ultimately led to the separation of registry and registrar functions.

Jon Crowcroft and Mark Handley received multiple awards for their work on Internet technology in the 1990s and 2000s. Karen Banks pioneered the use of the Internet to empower women around the world.

Other protocols and networks 
The NPL team worked on internetworking and the European Informatics Network, a datagram network linking Euratom, the French research centre INRIA and the UK’s National Physical Laboratory. The transport protocol of the EIN was the basis of the one adopted by the International Networking Working Group.

British along with French research contributed to the development of the X.25 standard by the CCIT in 1976. Logica, together with the French company SESA, set up a joint venture in 1975 to undertake the Euronet development, using X.25 protocols to form virtual circuits. It established a network linking a number of European countries before being handed over to national PTTs In 1984.

Based on the Coloured Book protocols defined by the UK academic community in 1975, Post Office Telecommunications developed a public packet switching network, EPSS. This was the first public data network in the UK when it began operating in 1977. The Coloured Book protocols gained some acceptance internationally as the first complete X.25 standard, and gave the UK "several years lead over other countries".

EPSS was replaced with the Packet Switch Stream using X.25 in 1980. PSS connected to an International Packet Switched Service (IPSS), created in 1978 in a collaboration between Post Office Telecommunications and two US telecoms companies. Four companies provided electronic mail services in Britain in 1985, enabling subscribers to send email over telephone connections or data networks such as Packet Switch Stream.

A number of local and research networks in the 1970s serving the Science and Engineering Research Council community became SRCnet, later called SERCnet. In the early 1980s a standardisation and interconnection effort started based on X.25 and the Coloured Book protocols. Known as the United Kingdom Education and Research Networking Association (UK ERNA), and later JNT Association, this became JANET in 1984, the UK's high-speed academic and research network that linked all universities, higher education establishments, and publicly funded research laboratories.

Commercial networking services between the UK and the US were being developed in late 1990.

The National Computing Centre publication 'Why Distributed Computing' which came from considerable research into future configurations for computer systems, resulted in the UK presenting the case for an international standards committee to cover this area at the ISO meeting in Sydney in March 1977. This international effort ultimately led to the OSI model as an international standard, published in 1984. For a period in 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.

In 1991, JANET adopted Internet Protocol on the existing network. In the same year, Dai Davies introduced Internet technology into the pan-European backbone, EuropaNet, which was built on the X.25 protocol.

World Wide Web 

In 1989, Tim Berners-Lee, working at CERN in Switzerland, wrote a proposal for "a large hypertext database with typed links". The following year, he specified HTML, the hypertext language, and HTTP, the protocol. These concepts became a world-wide information system known as the World Wide Web (WWW). Operating on the Internet, it allows documents to be created for reading or accessing services with connections to other documents or services, accessed by clicking on hypertext links, enabling the user to navigate from one document or service to another. Nicola Pellow worked with Berners-Lee and Robert Cailliau on the WWW project at CERN.

BT (British Telecommunications plc) began using the WWW in 1991 during a collaborative project called the Oracle Alliance Program.  It was founded in 1990 by Oracle Corporation, based in California, to provide information for its corporate partners and about those partners.  BT became involved in May 1991.  File sharing was required as part of the program and, initially, floppy disks were sent through the post. Then in July 1991 access to the Internet was implemented by BT network engineers using the BT packet switching network. A link was established from Ipswich to London for access to the Internet backbone. The first file transfers made via a NeXT-based WWW interface were completed in October 1991.

An early attempt to provide access to the Web on television was being developed in 1995.

Dial-up 

Pipex was established in 1990 and began providing dial-up Internet access in March 1992, the UK's first commercial Internet provider. By November 1993 Pipex provided Internet service to 150 customer sites. One of its first customers was Demon Internet which popularised dial up modem-based internet access in the UK. Other commercial Internet service providers, and web-hosting companies aimed at small businesses and individuals, developed in the 1990s. By May 1998 Demon Internet had 180,000 subscribers.

This narrowband service has been almost entirely replaced by the new broadband technologies, and is now generally only used as a backup. BT trialled its first ISBN 'broadband' connection in 1992. The first commercial service was available from Telewest in 2000.

Broadband 

Broadband allowed the signal in one line to be split between telephone and Internet data, meaning users could be online and make phone calls at the same time. It also enabled faster connections, making it easier to browse the Internet and download files. Broadband Internet access in the UK was, initially, provided by a number of regional cable television and telephone companies which gradually merged into larger groups. The development of digital subscriber line (DSL) technology has allowed broadband to be delivered via traditional copper telephone cables. Also, Wireless Broadband is now available in some areas. These three technologies (cable, DSL and wireless) now compete with each other.

More than half of UK homes had broadband in 2007, with an average connection speed of 4.6 Mbit/s. Bundled communications deals mixing broadband, digital TV, mobile phone and landline phone access were adopted by forty per cent of UK households in the same year, up by a third over the previous year. This high level of service is considered the main driver for the recent growth in online advertising and retail.

In 2006 the UK market was dominated by six companies, with the top two taking 51%, these being Virgin Media with a 28% share, and BT at 23%.

As of July 2011 BT's share had grown by six percent and the company became the broadband market leader.

The UK broadband market is overseen by the government watchdog Ofcom. According to Ofcom's 2007 report the average UK citizen uses the Internet for 36 minutes every day.

The Ofcom Communications Market 2018 report provided updated UK broadband usage statistics. A standout statistic from the 2012 Ofcom report compared with the 2018 Ofcom report is that the 2012 report showed just 5% of adults had access and use of a Smart TV, this increased to 42% by 2018 exemplifying the extra bandwidth required by broadband providers on their networks.

Cable 
Cable broadband uses coaxial cables or optical fibre cables. The main cable service provider in the UK is Virgin Media and the current maximum speed available to their customers is 500Mbit/s (subject to change).

Digital subscriber line (DSL) 

Asymmetric digital subscriber line (ADSL) was introduced to the UK in trial stages in 1998 and a commercial product was launched in 2000. In the United Kingdom, most exchanges, local loops and backhauls are owned and managed by BT Wholesale, who then wholesale connectivity via Internet service providers, who generally provide the connectivity to the Internet, support, billing and value added services (such as web hosting and email).

As of October 2012, BT operate 5630 exchanges across the UK with the vast majority being enabled for ADSL. Only a relative handful have not been upgraded to support ADSL products – in fact it is under 100 of the smallest and most rural exchanges. Some exchanges, numbering under 1000, have been upgraded to support SDSL products. However, these exchanges are often the larger exchanges based in major towns and cities so they still cover a large proportion of the population. SDSL products are aimed more at business customers and are priced higher than ADSL services.

Unbundled local loop 

Many companies are now operating their own services using local loop unbundling. Initially Bulldog Communications in the London area and Easynet (through their sister consumer provider UK Online) enabled exchanges across the country from London to Central Scotland.

In November 2010, having purchased Easynet in the preceding months, Sky closed the business-centric UK Online with little more than a month's notice. Although Easynet continued to offer business-grade broadband connectivity products, UKO customers could not migrate to an equivalent Easynet service, only being offered either a MAC to migrate provider or the option of becoming a customer of the residential-only Sky Broadband ISP with an introductory discounted period. Also, some previously available service features like fastpath (useful for time-critical protocols like SIP) were not made available on Sky Broadband, leaving business users with a difficult choice particularly where UK Online were the only LLU provider. Since then, Sky Broadband has become a significant player in the quad play telecoms market, offering ADSL line rental and call packages to customers (who have to pay a supplement if they are not also Sky television subscribers).

Whilst Virgin Media is the nearest direct competitor, their quad play product is available to fewer homes given the fixed nature of their cable infrastructure. TalkTalk is the next DSL-based ISP with a mature quad play product portfolio (EE's being the merger of the Orange and T-Mobile service providers, and focusing their promotion on forthcoming fibre broadband and 4G LTE products).

Market consolidation and expansion has permitted service providers to offer faster and less expensives services with typical speeds of up to 24 Mbit/s downstream (subject to ISP and line length). They can offer products at sometimes considerably lower prices, due to not necessarily having to conform to the same regulatory requirements as BT Wholesale: for example, 8 unbundled LLU pairs can deliver 10 Mbit/s over 3775 m for half the price of a similar fibre connection.

In 2005, another company, Be, started offering speeds of up to 24 Mbit/s downstream and 2.5 Mbit/sec upstream using ADSL2+ with Annex M, eventually from over 1,250 UK exchanges. Be were taken over by O2's parent company Telefónica in 2007. On 1 March 2013 O2 Telefónica sold Be to Sky who have now migrated O2 and Be customers onto the somewhat slower Sky network.

Exchanges continue to be upgraded, subject to demand, across the country, although at a somewhat slower pace since BT's commencement of FTTC rollout plans and near-saturation in key geographical areas.

IPstream 
Up until the launch of "Max" services, the only ADSL packages available via BT Wholesale were known as IPstream Home 250, Home 500, Home 1000 and Home 2000 (contention ratio of 50:1); and Office 500, Office 1000, and Office 2000 (contention ratio of 20:1). The number in the product name indicates the downstream data rate in kilobits per second. The upstream data rate is up to 250 kbit/s for all products.

For BT Wholesale ADSL products, users initially had to live within 3.5 kilometres of the local telephone exchange to receive ADSL, but this limit was increased thanks to rate-adaptive digital subscriber line (RADSL), although users with RADSL possibly had a reduced upstream rate, depending on the quality of their line. There are still areas that cannot receive ADSL because of technical limitations, not least of which networks in housing areas built with aluminium cable rather than copper in the 1980s and 1990s, and areas served by optical fibre (TPON), though these are slowly being serviced with copper.

In September 2004, BT Wholesale removed the line-length/loss limits for 500 kbit/s ADSL, instead employing a tactic of "suck it and see" — enabling the line, then seeing if ADSL would work on it. This sometimes includes the installation of a filtered faceplate on the customer's master socket, so as to eliminate poor quality telephone extension cables inside the customer's premises which can be a source of high frequency noise.

In the past, the majority of home users used packages with 500 kbit/s (downstream) and 250 kbit/s (upstream) with a 50:1 contention ratio. However, BT Wholesale introduced the option of a new charging structure to ISPs which means that the wholesale service cost was the same regardless of the ADSL data rate, with charges instead being based on the amount of data transferred. Nowadays, most home users use a package whose data rate is only limited by the technical limitations of their telephone line. Initially this was 2 Mbit/s downstream. Until the advent of widespread FTTC, most home products were first ADSL Max-based (up to 7.15 Mbit/s), using ADSL G.992.1 and then later ADSL2+ (up to 21 Mbit/s).

Max and Max Premium 
Following successful trials, BT announced the availability of higher speed services known as BT ADSL Max and BT ADSL Max Premium in March 2006. BT made the "Max" product available to more than 5300 exchanges, serving around 99% of UK households and businesses.

Both Max services offered downstream data rates of up to 7.15 Mbit/s. Upstream data rates were up to 400 kbit/s for the standard product and up to 750 kbit/s for the premium product. (Whilst the maximum downstream data rate for IPStream Max is often touted as 8 Mbit/s, this is in fact misleading because, in a departure from previous practice, it actually refers to the gross ATM data rate. The maximum data rate available at the IP level is 7.15 Mbit/s; the maximum TCP payload rate – the rate one would actually see for file transfer – would be about 7.0 Mbit/s.)

The actual downstream data rate achieved on any given Max line is subject to the capabilities of the line. Depending on the stable ADSL synchronisation rate negotiated, BT's ‘20CN’ system applied a fixed rate limit from one of the following data rates: 160 kbit/s, 250, 500, 750 kbit/s, 1.0 Mbit/s, 1.25, 1.5, 1.75, 2.0 Mbit/s, then in 500 kbit/s steps up to 7.0 Mbit/s, then a final maximum rate of 7.15 Mbit/s.

Speeds 
On 13 August 2004 the ISP Wanadoo (formerly Freeserve and now EE in the UK) was told by the Advertising Standards Authority to change the way that they advertised their 512 kbit/s broadband service in Britain, removing the words "full speed" which rival companies claimed was misleading people into thinking it was the fastest available service.

In a similar way, on 9 April 2003 the Advertising Standards Authority ruled against ISP NTL, saying that NTL's 128 kbit/s cable modem service must not be marketed as "broadband". Ofcom reported in June 2005 that there were more broadband than dial-up connections for the first time in history.

In the third quarter of 2005 with the merger of NTL and Telewest, a new alliance was formed to create the largest market share of broadband users. This alliance brought about huge increases in bandwidth allocations for cable customers (minimum speed increasing from the industry norm of 512 kbit/s to 2 Mbit/s home lines with both companies planning to have all domestic customers upgraded to at least 4 Mbit/s downstream and ranging up to 10 Mbit/s and beyond by mid-2006.) along with the supply of integrated services such as Digital TV and Phone packages.

March 2006 saw the nationwide launch of BT Wholesale's up to “8 Mbit/s” ADSL services, known as ADSL Max. “Max”-based packages are available to end users on any broadband-enabled BT exchange in the UK.

Since 2003, BT has been introducing SDSL to exchanges in many of the major cities. Services are currently offered at upload/download speeds of 256 kbit/s, 512 kbit/s, 1 Mbit/s or 2 Mbit/s. Unlike ADSL, which is typically 256 kbit/s upload, SDSL upload speeds are the same as the download speed. BT usually provide a new copper pair for SDSL installs, which can be used only for the SDSL connection. At a few hundred pounds a quarter, SDSL is significantly more expensive than ADSL, but is significantly cheaper than a leased line. SDSL is marketed to businesses and offers low contention ratios, and in some cases, a service level agreement. At present, the BT Wholesale SDSL enablement programme has stalled, most probably due to a lack of uptake.

Still in the year 2015 it was common in highly developed areas like the London Aldgate region for consumers to be limited to speeds of up to 8 Mbit/s for ADSL services. This had a major effect in the London rental market as limited broadband service can affect the readiness of prospective tenants to sign a rental lease.

Developments since 2006 

Since 2006, the UK market has changed significantly; companies that previously provided telephone and television subscriptions also began to offer broadband.

TalkTalk offered customers ‘free’ broadband if they had a telephone package. Orange responded by offering ‘free’ broadband for some mobile customers. Many smaller ISPs now offer similar packages. O2 also entered the broadband market by taking over LLU provider Be, while Sky (BSkyB) had already taken over LLU broadband provider Easynet. In July 2006, Sky announced 2 Mbit/s broadband to be available free to Sky TV customers and a higher speed connection at a lower price than most rivals.

In 2007 BT announced service trials for ADSL2+. Entanet, BT Wholesale and BT Retail were chosen as the three service providers for the first service trial in the West Midlands

In 2011, BT began offering 100Mbit/s FTTP broadband in Milton Keynes. The service in 2014 operates to speeds in excess of 300Mbit/s.

Virgin Media stated that 13 million UK homes are covered by their optical fibre broadband network, and that by the end of 2012 would be able to offer 100Mb broadband. There are currently over 100 towns in the UK that have access to this service.

In October 2011, British operator Hyperoptic launched a 1Gbit/sec FTTH service in London.

In October 2012, British operator Gigler UK launched a 1Gbit/sec down and 500Mbit/sec up FTTH service in Bournemouth using the CityFibre network.

In contrast to development in cities, in rural areas certain people in 2014 still suffered connection speeds below 256 kbit/s during daytimes and only can achieve speeds of more than 1 Mbit/s during nighttimes.

Wireless broadband 
The term "wireless broadband" generally refers to the provision of a wireless router with a broadband connection, although it can also refer to alternative wireless methods of broadband delivery, such as satellite or radio-based technology. These alternative delivery models are often deployed in areas that are physically or commercially unfeasible to reach by traditional fixed methods.

Mobile broadband 

Mobile broadband is high-speed Internet access provided by mobile phone operators using a device that requires a SIM card to access the service (such as the Huawei E220).

A new mobile broadband technology emerging in the United Kingdom is 4G which hopes to replace the old 3G technology currently in use and could see download speeds increased to 300Mbit/s. The company EE have been the first company to start developing a  full scale 4G network throughout the United Kingdom. This was later followed by other telecommunications companies in the UK such as O2 (Telefónica) and Vodafone.

Children's access to the Internet 
Educational computer networks are maintained by organisations such as JANET and East Midlands Public Services Network.

According to a 2017 Ofcom report named 'Children and Parents: Media Use and Attitudes Report' more younger children are going online than in 2016 with much of the growth coming from increased use of tablets.

A survey on UK school children's access to the Internet commissioned by security company Westcoastcloud in 2011 found half have no parental controls installed on their internet connected devices and half of parents said they have concerns about the lack of controls installed on their children's Internet devices.

Call for better oversight 

In June 2018 Tom Winsor, Her Majesty’s chief inspector of constabulary, said technologies like encryption should be breakable if law enforcers have a warrant.  Winsor said the public was running out of  patience with organisations like Facebook, Telegram and WhatsApp.  Winsor said, “There is a handful of very large companies with a highly dominant influence over how the internet is used. In too many respects, their record is poor and their reputation tarnished.  The steps they take to make sure their services cannot be abused by terrorists, paedophiles and organised criminals are inadequate; the commitment they show and their willingness to be held to account are questionable.”