Naked DSL

A naked DSL (a.k.a. standalone or dry loop DSL) is a digital subscriber line (DSL) without a PSTN (analogue telephony) service — or the associated dial tone. In other words, only a standalone DSL Internet service is provided on the local loop. The original concept of DSL was to use existing telephone lines for high speed data communication, with DSL and telephone services coexisting on the same phone line - but increasingly customers may require only the Internet service - and see no need for the traditional phone service. In Regular DSL, data transmission is carried on inaudible high frequencies on a standard Plain Old Telephone Service (POTS) telephone line.

Echo suppression and cancellation

echo cancellationecho cancellerecho suppressor
Until recently echo cancellation only needed to apply to the voice bandwidth of telephone circuits. PSTN calls transmit frequencies between 300 Hz and 3 kHz, the range required for human speech intelligibility. Videoconferencing is one area where full bandwidth audio is transceived. In this case, specialised products are employed to perform echo cancellation. Echo suppression may have the side-effect of removing valid signals from the transmission. This can cause audible signal loss that is called "clipping" in telephony, but the effect is more like a "squelch" than amplitude clipping. In an ideal situation then, echo cancellation alone will be used.

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.

PSTN network topology

A PSTN network topology is the switching network topology of a telephone network connected to the public switched telephone network (PSTN). In the United States and Canada, the Bell System network topology was the switching system hierarchy implemented and operated from the late 1940s to the 1980s for the purpose of integrating the diverse array of local telephone companies and telephone numbering plans to achieve nationwide Direct Distance Dialing (DDD) by telephone subscribers. It was the precursor of the world-wide interconnected public switched telephone network (PSTN).

Area codes 450 and 579

450 and 579450450, 579
Area codes 450 and 579 are telephone area codes in the Canadian province of Quebec, encompassing the off-island suburbs of Montreal, which is served by area codes 514 and 438. Among the cities served by area code 450 are Longueuil and Laval. The communities of Ormstown, Huntingdon, Boucherville, Varennes, Roussillon, Joliette, Saint-Hyacinthe, Granby, Chambly, Saint-Jean-sur-Richelieu and Vaudreuil-Dorion are also part of this area code.

Texts From Last Night

The texts are sent in by people who wake in the morning "to find regrettable messages sent to or from their mobile phones". The receiver then sends the allegedly discovered text into this website. The copies of the messages do not show the phone numbers, but only area codes. Since the texts are often similar to late night drunk dials, they're often graphic and sexual in nature, thus not safe for work. From a sociological perspective, the website is a "living document of twentysomething life in 2009". While TFLN has many "blackout drinking, sex, and vomit stories", there is also an extended discussion taking place about morality. The texts show how humans "interact with drugs and alcohol".

Area code 770

770770; 404; 678
Currently, cell phone subscribers in the region can choose from either the 770 or 470 area code when signing up for service. When the area was originally divided in 1995, most cellphones stayed with 404, which balanced the fact that most of the landline area went to 770. Atlanta was the first city in the United States to have mandatory 10-digit dialing throughout its metro area, roughly coinciding with the 1996 Summer Olympics in Atlanta.

Mobile-to-mobile convergence

The term mobile to mobile calling is used in many mobile phone plans to refer to making calls to other mobile phones using the same provider's network--which is often cheaper than other calls. Mobile to mobile convergence (MMC) is a term to describe a technology used in modern computing and telephony. The term is an offshoot of fixed mobile convergence (FMC) and uses dual mode (cellular network and WiFi) phones with a special software client and an application server to connect voice calls and business applications via a VoWLAN and/or through a cellular service.

Communications in Iran

Technology start-ups in Irancommunicatione-commerce
Iran's national Internet connectivity infrastructure is based on two major networks: the public switched telephone network (PSTN) and the public data network. The PSTN provides a connection for end-users to Internet service providers (ISPs) over mostly digital lines and supports modem-based connections. The Data Communication Company of Iran (DCI), a subsidiary of TCI, operates the public data network. Iran's external Internet links use the basic Internet protocol of TCP/IP (transmission control protocol/Internet protocol) via satellite exclusively.

Asynchronous transfer mode

ATMAsynchronous Transfer Mode (ATM)virtual circuit identifier
ATM is a core protocol used over the SONET/SDH backbone of the public switched telephone network (PSTN) and Integrated Services Digital Network (ISDN), but its use is declining in favour of all IP. ATM provides functionality that is similar to both circuit switching and packet switching networks: ATM uses asynchronous time-division multiplexing, and encodes data into small, fixed-sized packets (ISO-OSI frames) called cells. This differs from approaches such as the Internet Protocol or Ethernet that use variable sized packets and frames. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins.

Remote concentrator

In modern telephony a remote concentrator, remote concentrator unit (RCU), or remote line concentrator (RLC) is a concentrator at the lowest level in the telephone switch hierarchy. Subscribers' analogue telephone/PSTN lines are terminated on concentrators. They have three main functions, namely: Only a few hundred telephone lines attach to each remote concentrator. In North America concentrators are located in a serving area interface (SAI) or other enclosure in each neighborhood. In Europe the buildings which once contained local Strowger switch telephone exchanges are now usually empty except for a remote concentrator.

Split plan

In telephony, a split plan is the practice of introducing a new area code by dividing an existing area code's territory and applying the new area code to one of the resulting divisions, replacing the existing area code within that section. Split plans are used as growth in demand for telephone numbers (due to the increase in use of pagers, fax machines, and cellular phones) require new area codes in increasingly densely populated areas.

Telecommunications in Belgium

The telephone system itself is highly developed and technologically advanced, with full automation in facilities that handle domestic and international telecom. Domestically speaking, the county has a nationwide cellular telephone system and an extensive network of telephone cables. Telephone regulation is a national competency. The country code for Belgium is 32 and the international call prefix is 00. A telephone number in Belgium is a sequence of nine or ten numbers dialled on a telephone to make a call on the telephone network in Belgium. Belgium is under a closed telephone numbering plan, but retains the trunk code, "0", for all national dialling.


IPKall was a public switched telephone network to voice over IP call forwarding service. Users were able to register with the service to obtain a phone number chosen from several Washington State area codes and have all calls to that number forwarded to their Session Initiation Protocol or Inter-Asterisk eXchange uniform resource identifier, including an Asterisk server. The telephone company that provided IPKall numbers is International Telcom; they also provide a flat-rate $1/month area code 206 inbound fax service as Faxaway, a non-free voice and fax service as Kall8 (with toll-free or US local numbers) and the Kallback and KallCents discount outbound long-distance services.

Origination (telephony)

Origination in VOIP telephony refers to calls that originate in the PSTN public switched telephone network and are carried to their destination over the Internet. A VoIP call is initiated between two points, the initiation point is known as originator and the destination point is known as terminator. An Internet Telephony Service Provider (ITSP) involved in the origination of telephone calls usually offers either or both of “PC to Phone calls” and “Phone to Phone calls”. The two major business models for VoIP Originator are “Prepaid” and “Postpaid”. Hardware requirements for VoIP origination are simple.

Mobile Telephone Switching Office

Its subordinate BSC/RNC are responsible for assigning frequencies to each call, reassigning frequencies for handoffs, controlling handoffs so a mobile phone leaving one cell (formally known as BTS)'s coverage area, can be switched automatically to a channel in the next cell. All cellular systems have at least one MTSO which will contain at least one MSC. The MSC is responsible for switching calls to mobile units as well as to the local telephone system, recording billing data and processing data from the cell site controllers. The MSC is connected to a close telephone exchange by a trunk group. This provides an interface to the (Public Switched Telephone Network) (PSTN).

Local call

local phone calls
In telephony, the term local call has the following meanings: Typically, local calls have shorter numbers than long distance calls, as the area code may not be required. However, this is not true in parts of the United States and Canada that are subject to overlay plans or many countries in Europe that require closed dialing plans. Toll free (e.g. "800" numbers in the United States) are not necessarily local calls; despite being free to the caller, any charge due for the distance of the connection is charged to the called party.

Terrestrial Trunked Radio

TETRATETRA radio systemTETRA radio
TETRA terminals can act as mobile phones (cell phones), with a full-duplex direct connection to other TETRA Users or the PSTN. Emergency buttons, provided on the terminals, enable the users to transmit emergency signals, to the dispatcher, overriding any other activity taking place at the same time. The main advantages of TETRA over other technologies (such as GSM) are: Further information is available from the TETRA Association (formerly TETRA MoU) and the standards can be downloaded for free from ETSI. Its main disadvantages are: Up to 7.2 kbit/s per timeslot, in the case of point-to-point connections, and 3.5 kbit/s per timeslot in case of IP encapsulation.


Cable and Wireless OptusSingTel/OptusSingtel Optus
The long distance calling rates on offer were initially available by consumers dialing 1 before the area code and phone number. Following this, a ballot process was conducted by then regulator AUSTEL, with customers choosing their default long distance carrier. Customers who made no choice or refused to respond to the mailout campaign automatically remained as a Telstra long distance customer. Customers who remained with Telstra could dial the override code of 1456 before the area code and phone number to manually select Optus as the carrier for that single call.

Mass call event

overload the systemmillions of extra people and their calls
However, it can also apply to landline phones, in which not enough trunking telephone circuits are available into and out of any given telephone exchange or equivalent switching office at any level of the public switched telephone network (PSTN). An MCE is typically caused by a sudden disaster of some sort, such as an earthquake or explosion. One of the earliest examples was the Iroquois Theatre Fire in Chicago in 1903. The 1963 Kennedy assassination represented a mass call event for Washington, DC.

Rate center

rate centre
In the North American Numbering Plan, a rate center (rate centre in Canada) is a geographically-specified area used for determining mileage and/or usage dependent rates in the public switched telephone network. Unlike a wire center (which is the actual physical telephone exchange building), a rate center is a regulatory construct created primarily for billing purposes. Each rate center is associated with: A rate center may contain one or multiple physical wire centers; conversely, it may merely be a legal fiction retained for billing purposes with its actual subscribers served from the same physical switch as an adjacent community.

Japanese abbreviated and contracted words

contractedJapanese method of abbreviationabbreviation
Japanese "Dial Q2" premium-rate telephone numbers start with 0990. S, M: used for sadism and masochism respectively, often referring to mild personality traits rather than sexual fetishes. "SM" is also used for sadomasochism, instead of "S&M" used in English, in a more sexual context. W: The English word "double." Japanese people sometimes pronounce the letter "double." For example, ”Wデート” (W deeto) means "double date(s)"; "WW Burger" from Freshness Burger has double beef and double cheese.

Advanced Mobile Phone System

AMPSanalogTotal Access Communication System
Motorola had long produced mobile telephones for automobiles, but these large and heavy models consumed too much power to allow their use without the automobile's engine running. Mitchell's team, which included the gifted Dr. Martin Cooper, developed portable cellular telephony, and Mitchell was among the Motorola employees granted a patent for this work in 1973. The first call on the prototype connected, reportedly, to a wrong number. While Motorola was developing a cellular phone, from 1968-1983 Bell Labs worked out a system called Advanced Mobile Phone System (AMPS), which became the first cellular network standard in the United States.

Area code 816

However, in 1951 a third NPA, area code 417, was created for the southwest, including the cities of Branson, Joplin, and Springfield. By late 1996 the proliferation of cell phones, especially in the Kansas City area, and other market reforms related to deregulation by the Telecommunications Act of 1996, required that northwestern Missouri received an additional area code. The supply of telephone numbers was further limited because the Kansas City LATA extends some distance into eastern Kansas, meaning that several numbers in area code 913, the area code for most of the Kansas side of the Kansas City area, were not available for use.