Bit per second
In information theory, a bit per second (bit/s or b/s) is a unit used to express the number of bits passing a designated point per second.
For example, for two-condition serial transmission in a single channel in which each significant condition represents a bit, i.e. a 0 or a 1, the bit rate in bits per second and the baud have the same numerical value only if each bit occurs in a unit interval. In this case, the data signaling rate in bits per second is 1/T, where T is the unit interval.
Notes:
- Binary prefixes apply, such as kilobit/s and megabit/s, usually in their decimal SI variant, i.e. 1 Mbit/s means 106 = 1,000,000 bit/s, not 220 = 1,048,576 bit/s.
- The colloquial abbreviations bps, kbps, Mbps and so on are not in accordance with international standards and are therefore deprecated. Usage in telecommunications is particularly deprecated in comparison to the software industry, due to bandwidth being measured in multiples of the the telephone data rate of 64,000 bits per second (8-bit sample data at 8000 hertz). A "32 kbps data rate" would colloquially refer to 32,000 bits per second, whereas a "32 KB file" would colloquially refer to a 32,768 byte (215) file.
- When abbreviated there is no plural-s behind the "bit".
- B/s (with capitalized B) means "byte per second", where one byte is usually equal to eight bits. To avoid confusion it's usually best to spell out "byte" and "bit".
See also
Based upon Federal Standard 1037C and MIL-STD-188.
