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In communication networks, network throughput is the rate of successful message delivery over a communication channel, such as Ethernet or packet radio. The data these messages belong to may be delivered over a physical or logical link, or it can pass through a certain network node. Throughput is usually measured in bits per second, and sometimes in data packets per second or data packets per time slot.
In telecommunication and electronics, baud is a common unit of measurement of symbol rate, which is one of the components that determine the speed of communication over a data channel.
In digital transmission, the number of bit errors is the number of received bits of a data stream over a communication channel that have been altered due to noise, interference, distortion or bit synchronization errors.
In telecommunication, data signaling rate (DSR), also known as gross bit rate, is the aggregate rate at which data passes a point in the transmission path of a data transmission system.
- The DSR is usually expressed in bits per second.
- The data signaling rate is given by where m is the number of parallel channels, ni is the number of significant conditions of the modulation in the i-th channel, and Ti is the unit interval, expressed in seconds, for the i-th channel.
- For serial transmission in a single channel, the DSR reduces to (1/T)log2n; with a two-condition modulation, i. e. n = 2, the DSR is 1/T, according to Hartley's law.
- For parallel transmission with equal unit intervals and equal numbers of significant conditions on each channel, the DSR is (m/T)log2n; in the case of a two-condition modulation, this reduces to m/T.
- The DSR may be expressed in bauds, in which case, the factor log2ni in the above summation formula should be deleted when calculating bauds.
- In synchronous binary signaling, the DSR in bits per second may be numerically the same as the modulation rate expressed in bauds. Signal processors, such as four-phase modems, cannot change the DSR, but the modulation rate depends on the line modulation scheme, in accordance with Note 4. For example, in a 2400 bit/s 4-phase sending modem, the signaling rate is 2400 bit/s on the serial input side, but the modulation rate is only 1200 bauds on the 4-phase output side.
In telecommunication, effective data transfer rate is the average number of units of data, such as bits, characters, blocks, or frames, transferred per unit time from a source and accepted as valid by a sink.
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In computer technology, transfers per second and its more common secondary terms gigatransfers per second (abbreviated as GT/s) and megatransfers per second (MT/s) are informal language that refer to the number of operations transferring data that occur in each second in some given data-transfer channel. It is also known as sample rate, i.e. the number of data samples captured per second, each sample normally occurring at the clock edge. The terms are neutral with respect to the method of physically accomplishing each such data-transfer operation; nevertheless, they are most commonly used in the context of transmission of digital data. 1 MT/s is 106 or one million transfers per second; similarly, 1 GT/s means 109, or equivalently in the US/short scale, one billion transfers per second.
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In telecommunications, data-transfer rate is the average number of bits (bitrate), characters or symbols (baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are multiples of bits per second (bit/s) and bytes per second (B/s). For example, the data rates of modern residential high-speed Internet connections are commonly expressed in megabits per second (Mbit/s).
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References
This article incorporates public domain material from the General Services Administration document: "Federal Standard 1037C".(in support of MIL-STD-188)
