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Signaling System No. 6
Signaling System No. 6 (SS6) was introduced in the 1970s as an early common channel signalling method for telecommunication trunks between international switching centers (ISCs). It is specified in CCITT Recommendations Q.251-Q.300.ITU-T Recommendation Q.251-Q.300 - Specifications of Signalling System No. 6 The system had limited applications since at that time the predecessor systems (C5) and C4 were widely in use, but there was a need to experience common channel working on a fast digital basis. Traffic switching in the ISCs was then typically handled by |
Common Channel Signaling
In telecommunication, common-channel signaling (CCS), or common-channel interoffice signaling (CCIS), is the transmission of control information ''(signaling)'' via a separate channel than that used for the messages, The signaling channel usually controls multiple message channels. In the public switched telephone network (PSTN) one channel of a communications link is typically used for the sole purpose of carrying signaling for establishment and tear down of telephone calls. The remaining channels are used entirely for the transmission of voice messages. In most cases, a single channel is sufficient to handle the call setup and call clear-down traffic for numerous bearer (voice and data) channels. The technical alternative to CCS is channel-associated signaling (CAS), in which each bearer channel has a dedicated signaling channel. CCS offers the following advantages over CAS, in the context of the PSTN: * Faster call set-up time * Greater trunking efficiency due to the quick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Register Signalling
In telecommunications, register signaling provides addressing information, such as the calling and/or called telephone number. R2 register signaling is an example. This is contrasted with line signaling Line signaling is a class of telecommunications signaling protocols. Line signaling is responsible for off-hook, ringing signal, answer, ground start, on-hook unidirectional supervision messaging in each direction from calling party to ca .... References Telephony signals {{telephony-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analogue Signal
An analog signal or analogue signal (see spelling differences) is any continuous signal representing some other quantity, i.e., ''analogous'' to another quantity. For example, in an analog audio signal, the instantaneous signal voltage varies continuously with the pressure of the sound waves. In contrast, a digital signal represents the original time-varying quantity as a sampled sequence of quantized values which imposes some bandwidth and dynamic range constraints on the representation. The term ''analog signal'' usually refers to electrical signals; however, mechanical, pneumatic, hydraulic and other systems may also convey or be considered analog signals. Representation An analog signal uses some property of the medium to convey the signal's information. For example, an aneroid barometer uses rotary position as the signal to convey pressure information. In an electrical signal, the voltage, current, or frequency of the signal may be varied to represent the informa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circuit ID
A circuit ID is a company-specific identifier assigned to a data or voice network connection between two locations. This connection, often called a circuit, may then be leased to a customer referring to that ID. In this way, the circuit ID is similar to a serial number on any product sold from a retailer to a customer. Each circuit ID is unique, so a specific customer having many circuit connections sold to them would have many circuit IDs to refer to those connections. As an example of a use of the circuit ID, when a subscriber/customer has an issue (or trouble) with a circuit, they may contact the Controlling Local Exchange Carrier (Controlling LEC) telecommunications provider, identifying the circuit that has the issue by giving the LEC that circuit ID reference. The LEC would refer to their internal records for this circuit ID to take corrective action on the designated circuit. Telecom circuit ID formats Although telecommunication providers are not required to follow any s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modem
A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by modulating one or more carrier wave signals to encode digital information, while the receiver demodulates the signal to recreate the original digital information. The goal is to produce a signal that can be transmitted easily and decoded reliably. Modems can be used with almost any means of transmitting analog signals, from light-emitting diodes to radio. Early modems were devices that used audible sounds suitable for transmission over traditional telephone systems and leased lines. These generally operated at 110 or 300 bits per second (bit/s), and the connection between devices was normally manual, using an attached telephone handset. By the 1970s, higher speeds of 1,200 and 2,400 bit/s for asynchronous dial connections, 4,800 bit/s for synch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leased Line A leased line is a private telecommunications circuit between two or more locations provided according to a commercial contract. It is sometimes also known as a private circuit, and as a data line in the UK. Typically, leased lines are used by businesses to connect geographically distant offices. Unlike traditional telephone lines in the public switched telephone network (PSTN) leased lines are generally not switched circuits, and therefore do not have an associated telephone number. Each side of the line is permanently connected, always active and dedicated to the other. Leased lines can be used for telephone, Internet, or other data communication services. Some are ringdown services, and some connect to a private branch exchange (PBX) or network router. The primary factors affecting the recurring lease fees are the distance between end stations and the bandwidth of the circuit. Since the connection does not carry third-party communications, the carrier can assure a spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] |
