Push-button telephoneThe push-button telephone is a telephone that has buttons or keys for dialing a telephone number, in contrast to having a rotary dial as in earlier telephone instruments. Western Electric experimented as early as 1941 with methods of using mechanically activated reeds to produce two tones for each of the ten digits and by the late 1940s such technology was field-tested in a No. 5 Crossbar switching system in Pennsylvania.
In-band signalingIn telecommunications, in-band signaling is the sending of control information within the same band or channel used for data such as voice or video. This is in contrast to out-of-band signaling which is sent over a different channel, or even over a separate network. In-band signals may often be heard by telephony participants, while out-of-band signals are inaccessible to the user. The term is also used more generally, for example of computer data files that include both literal data, and metadata and/or instructions for how to process the literal data.
TrunkingIn telecommunications, trunking is a technology for providing network access to multiple clients simultaneously by sharing a set of circuits, carriers, channels, or frequencies, instead of providing individual circuits or channels for each client. This is reminiscent to the structure of a tree with one trunk and many branches. Trunking in telecommunication originated in telegraphy, and later in telephone systems where a trunk line is a communications channel between telephone exchanges.
Satellite phoneA satellite telephone, satellite phone or satphone is a type of mobile phone that connects to other phones or the telephone network by radio link through satellites orbiting the Earth instead of terrestrial cell sites, as cellphones do. Therefore, they can work in most geographic locations on the Earth's surface, as long as open sky and the line-of-sight between the phone and the satellite are provided. Depending on the architecture of a particular system, coverage may include the entire Earth or only specific regions.
Prank callA prank call (also known as a crank call) is a telephone call intended by the caller as a practical joke played on the person answering. It is often a type of nuisance call. It can be illegal under certain circumstances. Recordings of prank phone calls became a staple of the obscure and amusing cassette tapes traded among musicians, sound engineers, and media traders in the United States from the late 1970s. Among the most famous and earliest recorded prank calls are the Tube Bar prank calls tapes, which centered on Louis "Red" Deutsch.
Ringing toneRinging tone (audible ringing, also ringback tone) is a signaling tone in telecommunication that is heard by the originator of a telephone call while the destination terminal is alerting the receiving party. The tone is typically a repeated cadence similar to a traditional power ringing signal (ringtone), but is usually not played synchronously. Various telecommunication groups, such as the Bell System and the General Post Office (GPO) developed standards, in part taken over by the European Telecommunications Standards Institute (ETSI) and other standards bodies.
