|
Permanent Signal
Permanent signal (PS) in American telephony terminology, or permanent loop in British usage, is a condition in which a POTS line is off-hook without connection for an extended period of time.Telcordia Technologies, GR-505-CORE Issue 2, December 2005, ''Call Processing'', Section 4.5.2 This is indicated in modern switches by the silent termination after the off-hook tone times out and the telephone exchange computer puts the telephone line on its ''High & Wet list'' or ''Wetlist''. In older switches, however, a Permanent Signal Holding Trunk (PSHT) would play either an off-hook tone (''howler tone'') or a 480/500 Hz high tone (which would subsequently bleed into adjacent lines via crosstalk). Off-hook tone is a tone of increasing intensity that is intended to alert telephone users to the fact that the receiver has been left off the hook without being connected in a call. On some systems before the off-hook tone is played, an intercept message may be announced. The most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Telephony
Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunications services for the purpose of electronic transmission of voice, fax, or data, between distant parties. The history of telephony is intimately linked to the invention and development of the telephone. Telephony is commonly referred to as the construction or operation of telephones and telephonic systems and as a system of telecommunications in which telephonic equipment is employed in the transmission of speech or other sound between points, with or without the use of wires. The term is also used frequently to refer to computer hardware, software, and computer network systems, that perform functions traditionally performed by telephone equipment. In this context the technology is specifically referred to as Internet telephony, or voice over Internet Protocol (VoIP). Overview The first telephones were connected directly in pairs: each user had a separate telephone wire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Telephone Call
A telephone call, phone call, voice call, or simply a call, is the effective use of a connection over a telephone network between the calling party and the called party. Telephone calls are the form of human communication that was first enabled by the development of the telephone and several inventions in the mid- to late-19th century. Initial technology involved point-to-point electrical wire connections between telephone installations, until centralized exchanges evolved where Switchboard operator, telephone operators established each interconnection manually at a telephone switchboard after asking the calling party for their call destination. After the invention of automatic telephone exchanges in the 1890s, the process became increasingly automated, eventually leading to the widespread adoption of digital exchanges in the second half of the 20th century, including the transition to wireless communication via mobile telephone networks and cellular networks. With the developm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Lockout (telecommunication)
Lockout may refer to: * Lockout (industry), a type of work stoppage ** Dublin Lockout, a major industrial dispute between approximately 20,000 workers and 300 employers 1913–1914 * Lockout (sports), lockout in sports leagues ** MLB lockout, lockout in MLB ** NBA lockout, lockout in NBA ** NFL lockout, lockout in NFL ** NHL lockout, lockout in NHL * ''Lockout'' (film), a 2012 science fiction action film * ''Lock Out'' (film), a 1973 Spanish film * Lockout chip, a computer chip in a video game system to prevent use of unauthorized software * Lock-out device, part of a signaling system used on game shows * Regional lockout, a barrier to prevent media use outside of a specific region * Lockout (news filing), a kind of "dateline" appended to a news report * Lockout–tagout, a procedure to prevent unsafe activation of machinery * A period in some hostel A hostel is a form of low-cost, short-term shared sociable lodging where guests can rent a bed, usually a bunk bed in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
