Plain old telephone service (POTS), or plain ordinary telephone system, is a retronym for voice-grade telephone service employing analog signal transmission over copper loops. POTS was the standard service offering from telephone companies from 1876 until 1988 in the United States when the Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) was introduced, followed by cellular telephone systems, and voice over IP (VoIP). POTS remains the basic form of residential and small business service connection to the telephone network in many parts of the world. The term reflects the technology that has been available since the introduction of the public telephone system in the late 19th century, in a form mostly unchanged despite the introduction of Touch-Tone dialing, electronic telephone exchanges and fiber-optic communication into the public switched telephone network (PSTN).
A dial tone is a telephony signal sent by a telephone exchange or private branch exchange (PBX) to a terminating device, such as a telephone, when an off-hook condition is detected. It indicates that the exchange is working and is ready to initiate a telephone call. The tone stops when the first dialed digit is recognized. If no digits are forthcoming, the partial dial procedure is invoked, often eliciting a special information tone and an intercept message, followed by the off-hook tone, requiring the caller to hang up and redial.
Caller identification 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 Union—Telecommunication Standardization Sector (ITU-T) Recommendation Q.731.3.
An answering machine, answerphone, or message machine, also known as telephone messaging machine in the UK and some Commonwealth countries, ansaphone or ansafone, or telephone answering device (TAD), is used for answering telephone calls and recording callers' messages. When a telephone rings a set number of times predetermined by the call's recipient the answering machine will activate and play either a generic announcement or a customized greeting created by the recipient. Unlike voicemail, an answering machine is placed at the user's premises alongside—or incorporated within—the user's landline telephone, and unlike operator messaging, the caller does not talk to a human. As landlines become less important due to the shift to cell phone technology, and as unified communications evolve, the installed base of TADs is shrinking.
A voicemail system is a computer-based system that allows users and subscribers to exchange personal voice messages; to select and deliver voice information; and to process transactions relating to individuals, organizations, products, and services, using an ordinary phone. The term is also used more broadly to denote any system of conveying a stored telecommunications voice messages, including using an answering machine. Most cell phone services offer voicemail as a basic feature; many corporate private branch exchanges include versatile internal voice-messaging services, and *98 vertical service code subscription is available to most individual and small business landline subscribers.
A telephone call is a connection over a telephone network between the called party and the calling party.
Call waiting is a telephone service where a subscriber can accept a second incoming telephone call by placing an in-progress call on hold—and may also switch between calls. With some providers it can be combined with additional features such as conferencing, call forwarding, and caller ID. Call waiting is intended to alleviate the need to have more than one telephone line or number for voice communications.
Call forwarding, or call diversion, is a telephony feature of all telephone switching systems which redirects a telephone call to another destination, which may be, for example, a mobile or another telephone number where the desired called party is available. Call forwarding was invented by Ernest J. Bonanno. In North America, the forwarded line usually rings once to remind the customer using call forwarding that the call is being redirected. More consistently, the forwarded line indicates its condition by stutter dial tone. Call forwarding typically can redirect incoming calls to any other domestic telephone number, but the owner of the forwarded line must pay any toll charges for forwarded calls. Call forwarding is often enabled by dialing *72 followed by the telephone number to which calls should be forwarded. Once someone answers, call forwarding is in effect. If no one answers or the line is busy, the dialing sequence must be repeated to effect call forwarding. Call forwarding is disabled by dialing *73. This feature requires a subscription from the telephone company. Also available in some areas is Remote Access to call forwarding, which permit the control over call forwarding from telephones other than the subscriber's telephone. VOIP and cable telephone systems also allow call forwarding to be set up and directed via their web portals.
In telephony, an automated attendant allows callers to be automatically transferred to an extension without the intervention of an operator/receptionist. Many AAs will also offer a simple menu system. An auto attendant may also allow a caller to reach a live operator by dialing a number, usually "0". Typically the auto attendant is included in a business's phone system such as a PBX, but some services allow businesses to use an AA without such a system. Modern AA services can route calls to mobile phones, VoIP virtual phones, other AAs/IVRs, or other locations using traditional land-line phones or voice message machines.
A public-safety answering point (PSAP), sometimes called public-safety access point, is a call center where emergency/non-emergency calls initiated by any landline, mobile or Voice Over Internet Protocol ("VOIP") subscriber is terminated. It can also happen that when 112 is dialed in then a logic is implemented by mobile or network operators to route the call to the nearest police station. It is a call center in almost all the countries including Canada and the United States responsible for answering calls to an emergency telephone number for police, firefighting, and ambulance services. Trained telephone operators are also usually responsible for dispatching these emergency services. Most PSAPs are now capable of caller location for landline calls, and many can handle mobile phone locations as well, where the mobile phone company has a handset to location system. Some can also use voice broadcasting where outgoing voice mail can be sent to many phone numbers at once, in order to alert people to a local emergency such as a chemical spill.
GSM services are a standard collection of applications and features available over the Global System for Mobile Communications (GSM) to mobile phone subscribers all over the world. The GSM standards are defined by the 3GPP collaboration and implemented in hardware and software by equipment manufacturers and mobile phone operators. The common standard makes it possible to use the same phones with different companies' services, or even roam into different countries. GSM is the world's most dominant mobile phone standard.
Simplified Message Desk Interface (SMDI) is a protocol that defines the interface between a voice mail system and a phone system such as a PBX or public telephone switch. It was developed by Bell Labs. It is used to provide the voice mail system the information it needs to process the call. Each time a call is sent to the voice mail system, a message is sent using SMDI over a serial interface that identifies the line, the type of call, and the calling/called party numbers. The SMDI protocol also specifies a method for turning the message-waiting indicator (MWI) on and off on individual telephones.
Analog Display Services Interface (ADSI) is a telephony technology that is used in plain old telephone service (POTS) or computer-based private branch exchange (PBX) telephone service. It works in conjunction with a screen-based telephone ("screenphone") or other compatible customer-premises equipment (CPE) to provide the user with softkey access to telephone company or internal PBX custom calling features. It is an analog service because it uses analog frequency-shift keying (FSK) technology to interact with an LCD screen via short, low-baud rate, downloads to refresh and re-program softkeys in real-time.
Numbers on the Irish telephone numbering plan are regulated and assigned to operators by ComReg.
An intercept message is a telephone recording informing the caller that the call cannot be completed, for any of a number of reasons ranging from local congestion, to disconnection of the destination phone, number dial errors or network trouble along the route.
1-5-7-1 is the name of a family of calling features in the United Kingdom, for residential and business telephone lines and for mobile telephones, that are provided by BT Group and several other telephone service providers. The family is named after the telephone number 1571, the special service number that is used to access it. Call Minder is the name of BT's highest level of 1571 service.
In many voice telephone networks, anonymous call rejection (ACR) is a calling feature implemented in software on the network that automatically screens out calls from callers who have blocked their caller ID information.
iobi,, is a way of providing and managing telephone services over the Internet or PSTN-based telephone. Among capabilities, a registered customer could use a connected personal computer to dial a phone number and then speak to the person, they can check their voicemail messages over computer, or additionally customers could select to have specific callers permanently blocked from dialing the subscriber's telephone number, such as from telemarketers.
AUDIX is a voicemail server intended to be used with a Lucent/Avaya private branch exchange (PBX). AUDIX features many integrations with Avaya PBXes, such as capturing the extension of the calling party and announcing that person's name when announcing the attributes of a message, automatic identification of subscribers when they are dialing in to retrieve their messages, and activating and deactivating message-waiting indicators.
