In telephony, a customer's telephone line now typically ends at the remote concentrator box, where it is multiplexed along with other telephone lines for that neighborhood or other similar area. The multiplexed signal is then carried to the central switching office on significantly fewer wires and for much further distances than a customer's line can practically go. This is likewise also true for digital subscriber lines (DSL). Fiber in the loop (FITL) is a common method of multiplexing, which uses optical fiber as the backbone. It not only connects POTS phone lines with the rest of the PSTN, but also replaces DSL by connecting directly to Ethernet wired into the home.

Push-button telephone

push-button telephonepush-button dialingpushbutton telephones
* History of the telephone * Interactive voice response * Mobile phone * Timeline of the telephone * VoIP * History of the telephone * Interactive voice response * Mobile phone * Timeline of the telephone * VoIP


landlinefixed linefixed-line
In 2004, only about 45% of people in the United States between the ages of 12 and 17 owned cell phones. At that time, they had to rely on landline telephones. In just 4 years' time, that percentage climbed to about 71%. That same year, 2008, about 77% of adults owned a mobile phone. In the year 2013, 91% of adults in the United States owned a mobile phone. Almost 60% of those with a mobile had a smartphone. A National Health Interview Survey of 19,956 households by the Centers for Disease Control and Prevention released May 4, 2017 showed only 45.9 percent of U.S. households still had landlines, while 50.8 percent had only cell phones. Over 39 percent had both.

Managed facilities-based voice network

MFVNs are interconnected with the public switched telephone network (PSTN) and provide dialtone to end users. Historically, this was provided by equipment at Bell company central offices, however today's MFVNs can include a combination of access network (last mile network of copper, coaxial cable, or fiber optics), customer premises equipment (CPE), network switches and routers, network management systems, voice call servers, and gateways to the larger PSTN. MFVN providers include cable operators and telephone companies, but do not include Internet based providers such as Vonage, Magic Jack, and others that use the public internet to carry calls.

Touch-Tone Terrorists

It appeared under the name The Junkyard Willie Prank Call Tapes 4 due to its release shortly after the September 11 attacks. This CD features 22 prank calls. * The Junkyard Willie Movie: Lost In Transit: A straight-to-DVD movie based loosely on the Touch-Tone Terrorists characters. The film, released in 2008, includes one new prank call. * Customer Care Creeps: This is the 5th CD in the series, was released in two parts in 2009 and 2015 and contains 16 calls. * Caller ID spoofing * Jerky Boys * The Wack Pack * Tube Bar prank calls * Touch-tone Terrorists official Web Site * Homepage of the lost in transit movie


globalstarGlobalstar-2failures of the Globalstar network's satellites
A network of ground gateway stations provides connectivity from the 40 satellites to the public switched telephone network and Internet. A satellite must have a Gateway station in view to provide service to any users it may see. Twenty Four Globalstar Gateways are located around the world, including 7 in North America. Globalstar Gateways are the largest cellular base stations in the world with a design capacity for over 10,000 concurrent phone calls over a coverage area that is roughly 50% of the size of the USA. Globalstar supports CDMA technology such as the rake receiver and soft handoffs, so a handset may be talking via two spot beams to two Gateways for path diversity.

Speech coding

speech codingspeech codecspeech encoding
These techniques were available through the open research literature to be used for civilian applications, allowing the creation of digital mobile phone networks with substantially higher channel capacities than the analog systems that preceded them. The most common speech coding scheme is Code Excited Linear Prediction (CELP) coding, which is used for example in the GSM standard. In CELP, the modelling is divided in two stages, a linear predictive stage that models the spectral envelope and code-book based model of the residual of the linear predictive model.

Primary Rate Interface

PRIprimary rate interfaceprimary rate
* Non-Facility Associated Signalling * H channel * Caller ID spoofing


phonewordmnemonicphone word
* E.161 * Teledotcom * Telephone exchange names * Telephone numbering plan * Telephone number * Toll-free telephone number * Vanity plate * Custom Toll Free * T9 (predictive algorithm) nl:Naambellen ja:語呂合わせ * E.161 * Teledotcom * Telephone exchange names * Telephone numbering plan * Telephone number * Toll-free telephone number * Vanity plate * Custom Toll Free * T9 (predictive algorithm)


keypadnumeric keypadkeyboard
* Keyboard (computing) * Telephone keypad * Push-button telephone * Silicone rubber keypad * Numeric keypad * Keyboard technology * Mobile phone * Digital door lock * Arrow keys

Obscene phone call

obscene phone callTelephone scatologiatelephone scatophilia
* Courtship disorder * Dirty talk * Phone sex * Prank call * Sexual harassment * Strip search phone call scam * Why do some men make obscene phone calls? * Fact Sheet 3: How to Put an End to Unwanted or Harassing Phone Calls * Courtship disorder * Dirty talk * Phone sex * Prank call * Sexual harassment * Strip search phone call scam * Why do some men make obscene phone calls? * Fact Sheet 3: How to Put an End to Unwanted or Harassing Phone Calls

List of dialling codes in the United Kingdom

Dialling codesDialling codearea codes
The national telephone numbering plan is maintained by Ofcom, an independent regulator and competition authority for the UK communications industries. This list is based on the official standard, but includes defunct codes and historical changes, including the derivation of the two letter identities, in cases where known. The United Kingdom adopts an open telephone numbering plan for its public switched telephone network. Dialling codes do not correspond to specific political boundaries. For example, the Coventry dialling code covers a large area of Warwickshire and the Manchester dialling code covers part or all of several neighbouring towns.

List of telephone exchanges in London

170 telephone exchanges
NOTE: The United Kingdom adopts an open dialling plan for area codes within its public switched telephone network. Therefore, all area codes have a preceding 0 (zero) when dialling from within the United Kingdom. When dialling a UK number from abroad the zero must not be included, but replaced by the calling country's international call prefix followed by the 44, the country code for the UK. Thus a call to the Euston exchange discussed above from the United States would be to 011 (US international prefix) 44 20 (London) 73871234. The following exchanges are located outside Greater London, but use the London 020 dial code.

Area codes 416, 647, and 437

416416, 647416, 647, 437
Nonetheless, the GTA's rapid growth and the proliferation of cell phones, fax machines, and pagers made it obvious that the Golden Horseshoe needed another area code. In 1993, the 416 territory was cut back to just Metro Toronto (York, East York, North York, Etobicoke, Scarborough and Old Toronto), while area code 905 was assigned to most of Toronto's suburbs; it almost completely surrounds 416. The split began on October 13, 1993; permissive dialing of 416 continued throughout the Golden Horseshoe until January 1, 1994.

List of dialling codes in Brazil

Area/distance codeArea code63
*Area code 61 primarily serves the Federal District (comprising the national capital city, Brasília), but it also serves some surrounding municipalities in the State of Goiás, such as Formosa, Valparaíso de Goiás and Luziânia. Formerly, area code 61 was even larger and used to include northwestern Minas Gerais (Unaí, Paracatu), now in that state's area code 38. *The city of Alto Parnaíba, in the State of Maranhão, is conurbated with Santa Filomena, State of Piauí, and uses the latter state's area code 89 for landlines. Most local mobile phones, though, use Southern Maranhão area code 99.

Demarcation point

demarcation pointDanishDanes
Part 68) to allow safe connection of third-party telephone customer-premises equipment and wiring to the Public Switched Telephone Network (PSTN). The modern demarcation point is the network interface device (NID) or intelligent network interface device (INID) also known as a "smartjack". The NID is the telco's property. The NID may be outdoors (typically, mounted on the building exterior in a weatherproof box) or indoors. The NID is usually placed for easy access by a technician.

International rankings of Iran

International rankings of Iran in science and technologyInternational Rankings of Iran in EconomyInternational Rankings of Iran in Transport
The following are international rankings for Iran:

Telephone numbers in Brazil

+55Area codeBrazil
So, to call the international telephone number +cc-aa-nnnn-nnnn (where cc is the country code and aa the area code), one would dial 00-xx-cc-aa-nnnn-nnnn, where xx is the carrier selection code. Since international telephone numbers can have up to 15 digits, the maximum number of digits to be dialed is 19. For example, to call the number 555-0123 in Washington, D.C. (area code 202), United States (country code 1), using TIM as the chosen carrier (selection code 41), one would dial 00 41 1 202 555 0123.

Call forwarding

call forwardingforwardingGSM forwarding standard features codes
Call forwarding can also assist travelers who do not have international cell phone plans and who wish to continue to receive their voicemails through a VOIP voicemail very easily while abroad. * Follow-me * Hunting (telephony) * Remote call forwarding * GSM USSD codes - Unstructured Supplementary Service Data: list of standard GSM codes for network and SIM related functions * Call Forwarding User manual, Bell Canada * As of Jan 2012, Sprint charges 20 cents per minute for unconditional call forwarding, conditional call forwarding is included however. * Some carriers (including Verizon Wireless) use *71 for conditional forwarding although this is not standard.

Naked DSL

naked DSL
Naked DSL (both ADSL and VDSL) is provided by Bezeq telephony company to customers upon request, since most homes use both telephony and DSL lines as default, the service is provided only by demand. It's possible to request to remove the telephony line function at any given time without any restrictions or obligations. Chorus Limited is the wholesale provider for the vast majority of phone lines and it provides naked DSL services. All the major internet retailers provide a naked DSL service.

Local number portability

local number portabilitynumber portabilityported
Canada, South Africa and the United States are the only countries that offer full number portability transfers between both fixed lines and mobile phone lines, because mobile and fixed line numbers are mixed in the same area codes, and are billed identically for the calling party, the mobile user usually pays for incoming calls and texts; in other countries all mobile numbers are placed in higher priced mobile-dedicated area codes and the originator of the call to the mobile phone pays for the call. The government of Hong Kong has tentatively approved fixed-mobile number portability; however, as of July 2012, this service is not yet available.

Echo suppression and cancellation

echo cancellationecho cancellerecho suppressor
Today's telephony technology often employs echo cancellers in small or handheld communications devices via a software voice engine, which provides cancellation of either acoustic echo or the residual echo introduced by a far-end PSTN gateway system; such systems typically cancel echo reflections with up to 64 milliseconds delay. Since invention at AT&T Bell Labs echo cancellation algorithms have been improved and honed. Like all echo cancelling processes, these first algorithms were designed to anticipate the signal which would inevitably re-enter the transmission path, and cancel it out.

Telephone numbers in Belgium

+32BelgiumBelgian telephone numbers
The Telephone numbering plan is open, meaning that numbers have varying lengths (9 digits for landline phones of the formerly monopolistic company Belgacom, and 10 digits for other numbers incl. GSM cellphones). Area codes in Belgium are, excluding the leading '0', one or two digits long. Numbers are of variable length; landlines have a seven-digit subscriber number and a one-digit area code, while smaller cities have a six-digit subscriber number and a two-digit area code. All Belgian telephone numbers dialed within Belgium must use the leading '0' trunk code.