Editing Binary symmetric channel (section)

{{more footnotes|date=March 2013}}
A '''binary symmetric channel''' (or '''BSC<sub>p</sub>''') is a common [[communications channel]] model used in [[coding theory]] and [[information theory]]. In this model, a transmitter wishes to send a [[bit]] (a zero or a one), and the receiver will receive a bit. The bit will be "flipped" with a "crossover [[probability]]" of ''p'', and otherwise is received correctly. This model can be applied to varied communication channels such as telephone lines or [[disk drive]] storage.

The [[noisy-channel coding theorem]] applies to BSC<sub>p</sub>, saying that information can be transmitted at any rate up to the [[channel capacity]] with arbitrarily low error. The channel capacity is <math>1 - \operatorname H_\text{b}(p)</math> bits, where <math>\operatorname H_\text{b}</math> is the [[binary entropy function]]. Codes including Forney's code have been designed to transmit information efficiently across the channel.