The nominal bit rate (BR, nominal) is specified in units of
100 Megabits per second, rounded off to the nearest 100
Megabits per second. The bit rate includes those bits
necessary to encode and delimit the signal as well as those
bits carrying data information. A value of 0 indicates that
the bit rate is not specified and must be determined from the
transceiver technology. The actual information transfer rate
will depend on the encoding of the data, as defined by the
encoding value.