|
Digital Access Carrier System
Digital access carrier system (DACS) is the name used by British Telecom (BT Group plc) in the United Kingdom for a 0+2 pair gain system. Usage For almost as long as telephones have been a common feature in homes and offices, telecommunication companies have regularly been faced with a situation where demand in a particular street or area exceeds the number of physical copper pairs available from the pole to the exchange. Until the early 1980s, this situation was often dealt with by providing shared or 'party' lines, which were connected to multiple customers. This raised privacy problems since any subscriber connected to the line could listen to (or indeed, interrupt) another subscriber's call. With advances in the size, price, and reliability of electronic equipment, it eventually became possible to provide two normal subscriber lines over one copper pair, eliminating the need for party lines. The more modern ISDN technology based digital systems that perform this task ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BT Group Plc
BT Group plc (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 fixed-line, Internet access, broadband and Mobile telephony, mobile services in the UK, and also provides 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, Post Office Telecommunications. The ''British Telecom'' brand was introduced in 1980, and became independent of the R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caller ID
Caller identification (Caller ID) is a telephone service, available in analog and digital telephone systems, including voice over IP (VoIP), that transmits a caller's telephone number to the called party's telephone equipment when the call is being set up. The caller ID service may include the transmission of a name associated with the calling telephone number, in a service called Calling Name Presentation (CNAM). The service was first defined in 1993 in International Telecommunication UnionTelecommunication Standardization Sector (ITU-T) Recommendation Q.731.3. The information received from the service is displayed on a telephone display screen, on a separately attached device, or on other displays, such as cable television sets when telephone and television service is provided by the same vendor. Value to society includes allowing suicide-prevention hotlines to quickly identify a caller, and enabling businesses (for an example, restaurants and florists) to quickly have co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BT Group
BT Group plc (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 fixed-line, Internet access, broadband and Mobile telephony, mobile services in the UK, and also provides 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, Post Office Telecommunications. The ''British Telecom'' brand was introduced in 1980, and became independent of the R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modem
The Democratic Movement (, ; MoDem ) is a centre to centre-right political party in France, whose main ideological trends are liberalism and Christian democracy, and that is characterised by a strong pro-Europeanist stance. MoDem was established by François Bayrou to succeed the Union for French Democracy (UDF) and contest the 2007 legislative election, after his strong showing in the 2007 presidential election. Initially named the Democratic Party (''Parti démocrate''), the party was renamed "Democratic Movement", because there was already a small Democratic Party in France. MoDem secured an agreement with La République En Marche! (LRM) — later Renaissance (RE) — in the 2017 legislative election after Bayrou had endorsed the candidacy of Emmanuel Macron in February. The two parties have since been in alliance, as of late named Ensemble. The party's founder and leader Bayrou has served as Prime Minister of France since December 2024. History Background MoDem tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Access And Cross-connect System
A digital cross-connect system (DCS or DXC) is a piece of circuit-switched network equipment, used in telecommunications networks, that allows lower-level TDM bit streams, such as DS0 bit streams, to be rearranged and interconnected among higher-level TDM signals, such as DS1 bit streams. DCS units are available that operate on both older T-carrier/E-carrier bit streams, as well as newer SONET/SDH bit streams. DCS devices can be used for " grooming" telecommunications traffic, switching traffic from one circuit to another in the event of a network failure, supporting automated provisioning, and other applications. Having a DCS in a circuit-switched network provides important flexibility that can otherwise only be obtained at higher cost using manual " DSX" cross-connect patch panels. DCS devices "switch" traffic, but they are ''not'' packet switches—they switch ''circuits'', not packets, and the circuit arrangements they are used to manage tend to persist over very l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subscriber Loop Carrier
A subscriber loop carrier or subscriber line carrier (SLC) provides telephone exchange-like telephone interface functionality. SLC remote terminals are typically located in areas with a high density of telephone subscribers, such as a residential neighborhood, or very rural areas with widely dispersed customers, that are remote from the telephone company's central office (CO). Two or four T1 circuits (depending on the configuration) connect the SLC remote terminal to the central office terminal (COT), in the case of a universal subscriber loop carrier (USLC). An integrated subscriber loop carrier (ISLC) has its T-spans terminating directly in time division switching equipment in the telephone exchange. One system serves up to 96 customers. This configuration is more efficient than the alternative of having separate copper pairs between each service termination point (the subscriber's location) and the central telephone exchange. These systems are generally installed in cabinet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carrier Wave
In telecommunications, a carrier wave, carrier signal, or just carrier, is a periodic waveform (usually sinusoidal) that conveys information through a process called ''modulation''. One or more of the wave's properties, such as amplitude or frequency, are modified by an information bearing signal, called the ''message signal'' or ''modulation signal''. The carrier frequency is usually much higher than the message signal frequency; this is because it is usually impractical to transmit signals with low frequencies over long distances (due to attenuation). The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave (as in radio communication), or to allow several carriers at different frequencies to share a common physical transmission medium by frequency division multiplexing (as in a cable television system). The term originated in radio communication, where the carrier wave creates the waves which carry the information (mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Frequency
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper limit of audio frequencies that humans can hear (though these are not electromagnetic) and the lower limit of infrared frequencies, and also encompasses the microwave range. These are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves, so they are used in radio technology, among other uses. Different sources specify different upper and lower bounds for the frequency range. Electric current Electric currents that oscillate at radio frequencies (RF currents) have special properties not shared by direct current or lower audio frequency alternating current, such as the 50 or 60 Hz current used in electrical power distribution. * Energy from RF currents in conduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog Signal
An analog signal (American English) or analogue signal (British and Commonwealth English) is any continuous-time signal representing some other quantity, i.e., ''analogous'' to another quantity. For example, in an analog audio signal, the instantaneous signal voltage varies continuously with the pressure of the sound waves. In contrast, a digital signal represents the original time-varying quantity as a sampled sequence of quantized values. Digital sampling imposes some bandwidth and dynamic range constraints on the representation and adds quantization noise. The term ''analog signal'' usually refers to electrical signals; however, mechanical, pneumatic, hydraulic, and other systems may also convey or be considered analog signals. Representation An analog signal uses some property of the medium to convey the signal's information. For example, an aneroid barometer uses rotary position as the signal to convey pressure information. In an electrical signal, the voltage, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kent
Kent is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Essex across the Thames Estuary to the north, the Strait of Dover to the south-east, East Sussex to the south-west, Surrey to the west, and Greater London to the north-west. The county town is Maidstone. The county has an area of and had population of 1,875,893 in 2022, making it the Ceremonial counties of England#Lieutenancy areas since 1997, fifth most populous county in England. The north of the county contains a conurbation which includes the towns of Chatham, Kent, Chatham, Gillingham, Kent, Gillingham, and Rochester, Kent, Rochester. Other large towns are Maidstone and Ashford, Kent, Ashford, and the City of Canterbury, borough of Canterbury holds City status in the United Kingdom, city status. For local government purposes Kent consists of a non-metropolitan county, with twelve districts, and the unitary authority area of Medway. The county historically included south-ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Wales
South Wales ( ) is a Regions of Wales, loosely defined region of Wales bordered by England to the east and mid Wales to the north. Generally considered to include the Historic counties of Wales, historic counties of Glamorgan and Monmouthshire (historic), Monmouthshire, south Wales extends westwards to include Carmarthenshire and Pembrokeshire. In the western extent, from Swansea westwards, local people would probably recognise that they lived in both south Wales and west Wales. The Brecon Beacons National Park covers about a third of south Wales, containing Pen y Fan, the highest British mountain south of Cadair Idris in Snowdonia. A point of some discussion is whether the first element of the name should be capitalised: 'south Wales' or 'South Wales'. As the name is a geographical expression rather than a specific area with well-defined borders, style guides such as those of the BBC and ''The Guardian'' use the form 'south Wales'. In a more authoritative style guide, the Wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Subscriber Line
Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that are used to transmit digital data over telephone lines. In telecommunications marketing, the term DSL is widely understood to mean asymmetric digital subscriber line (ADSL), the most commonly installed DSL technology, for Internet access. In ADSL, the data throughput in the upstream (networking), upstream direction (the direction to the service provider) is lower, hence the designation of ''asymmetric'' service. In symmetric digital subscriber line (SDSL) services, the downstream and upstream data rates are equal. DSL service can be delivered simultaneously with plain old telephone service, wired telephone service on the same telephone line since DSL uses higher frequency bands for data transmission. On the customer premises, a DSL filter is installed on each telephone to prevent undesirable interaction between DSL and telephone service. The bit rate of consumer ADSL services typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
