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British Telephone Sockets
British telephone sockets were introduced in their current plug and socket form on 19 November 1981 by British Telecom to allow subscribers to connect their own telephones. The connectors are specified in British Standard BS 6312. Electrical characteristics of the telephone interface are specified by individual network operators, e.g. in British Telecom's SIN 351. Until recently, this socket contained an enclosed spark gap, SP1, that could safely flash over internally to provide high voltage surge protection. This component is no longer used due to negative effects on VDSL speeds. The socket includes a 1.8 µF capacitor (bell circuit) to feed the AC ringing and a 470 kΩ resistor (R1, out-of-service resistor) to permit remote testing when no telephones are plugged into any sockets. Additional internal extension (secondary) sockets are wired off the master socket (connected in parallel using the IDC system) but not containing the surge protector, bell circuit capacitor, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Telephone Connector
British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, the English language as spoken and written in the United Kingdom or, more broadly, throughout the British Isles * Celtic Britons, an ancient ethno-linguistic group * Brittonic languages, a branch of the Insular Celtic language family (formerly called British) ** Common Brittonic, an ancient language Other uses *''Brit(ish)'', a 2018 memoir by Afua Hirsch *People or things associated with: ** Great Britain, an island ** United Kingdom, a sovereign state ** Kingdom of Great Britain (1707–1800) ** United Kingdom of Great Britain and Ireland (1801–1922) See also * Terminology of the British Isles * Alternative names for the British * English (other) * Britannic (other) * British Isles * Brit (other) * Briton (d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Termination Equipment
upTwo simple NIDs, carrying six lines each, on the outside of a building upA German copper phone line termination box called '' Abschlusspunkt LinienTechnik'' (APL, " Demarcation point") In telecommunications, a network interface device (NID; also known by several other names) is a device that serves as the demarcation point between the carrier's local loop and the customer's premises wiring. Outdoor telephone NIDs also provide the subscriber with access to the station wiring and serve as a convenient test point for verification of loop integrity and of the subscriber's inside wiring. Naming Generically, an NID may also be called a network interface unit (NIU), telephone network interface (TNI), system network interface (SNI), or telephone network box. Australia's National Broadband Network uses the term '' network termination device'' or NTD. A smartjack is a type of NID with capabilities beyond simple electrical connection, such as diagnostics. An ''optical network term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications In New Zealand
Telecommunications in New Zealand are fairly typical for an industrialised country. Fixed-line broadband and telephone services are largely provided through copper-based networks, although fibre-based services are increasingly common. Spark New Zealand, Vodafone New Zealand, and 2degrees provide most services, although a number of smaller mobile virtual network operators also exist. History The first telegraph opened in New Zealand between the port of Lyttelton and Christchurch on 16 June 1862. The line was constructed along the Lyttelton - Christchurch railway line. The Vogel Era from 1870 saw a major expansion of the telegraph network, including an inter-island cable. Telegraph lines increased from in 1866 to in 1876. The first overseas telegraph cable between Australia and New Zealand began operation on 21 February 1876. The Electric Telegraph Department formed to manage the growing telegraph network was merged with Post Office Department to form the New Zealand Post ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crossover Cable
A crossover cable connects two devices of the same type, for example DTE-DTE or DCE-DCE, usually connected asymmetrically (DTE-DCE), by a modified cable called a crosslink. Such a distinction between devices was introduced by IBM. The crossing of wires in a cable or in a connector adaptor allows: * connecting two devices directly, output of one to input of the other, * letting two terminal (DTE) devices communicate without an interconnecting hub knot, i.e. PCs, * linking two or more hubs, switches or routers (DCE) together, possibly to work as one wider device. In contrast, a straight-through cable uses direct wiring to connect complementary devices, e.g. a PC to a switch. Concept Straight-through cables are used for most applications, but crossover cables are required in others. In a straight-through cable, pins on one end correspond exactly to the corresponding pins on the other end (pin 1 to pin 1, pin 2 to pin 2, etc.). Using the same wiring scheme at each end yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straight-through Cable
A crossover cable connects two devices of the same type, for example DTE-DTE or DCE-DCE, usually connected asymmetrically (DTE-DCE), by a modified cable called a crosslink. Such a distinction between devices was introduced by IBM. The crossing of wires in a cable or in a connector adaptor allows: * connecting two devices directly, output of one to input of the other, * letting two terminal (DTE) devices communicate without an interconnecting hub knot, i.e. PCs, * linking two or more hubs, switches or routers (DCE) together, possibly to work as one wider device. In contrast, a straight-through cable uses direct wiring to connect complementary devices, e.g. a PC to a switch. Concept Straight-through cables are used for most applications, but crossover cables are required in others. In a straight-through cable, pins on one end correspond exactly to the corresponding pins on the other end (pin 1 to pin 1, pin 2 to pin 2, etc.). Using the same wiring scheme at each end yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interconnection
In telecommunications, interconnection is the physical linking of a carrier's network with equipment or facilities not belonging to that network. The term may refer to a connection between a carrier's facilities and the equipment belonging to its customer, or to a connection between two or more carriers. In United States regulatory law, interconnection is specifically defined (47 C.F.R. 51.5) as "the linking of two or more networks for the mutual exchange of traffic." One of the primary tools used by regulators to introduce competition in telecommunications markets has been to impose interconnection requirements on dominant carriers. History United States Under the Bell System monopoly (post Communications Act of 1934), the Bell System owned the phones and did not allow interconnection, either of separate phones (or other terminal equipment) or of other networks; a popular saying was "Ma Bell has you by the calls". This began to change in the landmark case Hush-A-Phone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Telecom
BT Group plc (trade name, trading as BT and formerly British Telecom) is a British Multinational corporation, multinational telecommunications holding company headquartered in London, England. It has operations in around 180 countries and is the largest provider of Landline, fixed-line, Internet access, broadband and Mobile telephony, mobile services in the UK, and also provides Pay television, subscription television and Information technology, IT services. BT's origins date back to the founding in 1846 of the Electric Telegraph Company, the world's first public telegraph company, which developed a nationwide communications network. BT Group as it came to be started in 1912, when the General Post Office, a government department, took over the system of the National Telephone Company becoming the monopoly telecoms supplier in the United Kingdom. The Post Office Act of 1969 led to the GPO becoming a public corporation. The ''British Telecom'' brand was introduced in 1980, and be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADSL
Asymmetric digital subscriber line (ADSL) is a type of digital subscriber line (DSL) technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. ADSL differs from the less common symmetric digital subscriber line (SDSL). In ADSL, bandwidth and bit rate are said to be asymmetric, meaning greater toward the customer premises (downstream) than the reverse (upstream). Providers usually market ADSL as an Internet access service primarily for downloading content from the Internet, but not for serving content accessed by others. Overview ADSL works by using spectrum above the band used by voice telephone calls. With a DSL filter, often called ''splitter'', the frequency bands are isolated, permitting a single telephone line to be used for both ADSL service and telephone calls at the same time. ADSL is generally only installed for short distances from the telephone exchange (the las ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DSL Filter
A DSL filter (also DSL splitter or microfilter) is an analog low-pass filter installed between analog devices (such as telephones or analog modems) and a plain old telephone service (POTS) line. The DSL filter prevents interference between such devices and a digital subscriber line (DSL) service connected to the same line. Without DSL filters, signals or echoes from analog devices at the top of their frequency range can reduce performance and create connection problems with DSL service, while those from the DSL service at the bottom of its range can cause line noise and other problems for analog devices. The concept of a low pass filter for ADSL was first described in 1996 by Vic Charlton when working for the Canadian Operations Development Consortium: Low-Pass Filter On All Phones.Generic Operational Guidelines & Test Results for ADSL, Project Number 549R, 96-12-31 DSL filters are passive devices, requiring no power source to operate. Some high-quality filters may contain ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BT Infinity
BT Superfast Fibre (formerly BT Infinity) is a broadband service in the United Kingdom provided by BT Consumer, the consumer sales arm of the BT Group. The underlying network is fibre-to-the-cabinet (FTTC), which uses optical fibre for all except the final few hundred metres (yards) to the consumer, and delivers claimed download speeds of "up to 76 Mbit/s" and upload speeds of "up to 19 Mbit/s" depending on package selected. The fibre terminates in a new roadside cabinet containing a DSLAM, from where the final connection to the customer uses VDSL2 technology. Ofcom data gathered in November 2014 indicated that only 1% of 76 Mbit/s and 15% of 38 Mbit/s customers received the advertised speed. It adopted its present name on 23 May 2018 as part of BT's renaming of its entire broadband portfolio which is "designed to be simpler and more descriptive". Deployment Following a technical trial involving 50 homes in Foxhall, Ipswich, in January 2009, and operational ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vdsl
Very high-speed digital subscriber line (VDSL) and very high-speed digital subscriber line 2 (VDSL2) are digital subscriber line (DSL) technologies providing data transmission faster than the earlier standards of asymmetric digital subscriber line (ADSL) G.992.1, G.992.3 (ADSL2) and G.992.5 (ADSL2+). VDSL offers speeds of up to 52 Mbit/s Downstream (networking), downstream and 16 Mbit/s Upstream (networking), upstream, over a single twisted pair of copper wires using the frequency band from 25 kHz to 12 MHz. These rates mean that VDSL is capable of supporting applications such as high-definition television, as well as telephone services (voice over IP) and general Internet access, over a single connection. VDSL is deployed over existing wiring used for Plain old telephone service, analog telephone service and lower-speed DSL connections. This standard was approved by the International Telecommunication Union (ITU) in November 2001. Second-generation systems (VD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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