AT&T 3.0 manual B8ZS

Glossary

automatic-start tie Tie trunk on which incoming calls are routed to an operator

trunkor other designated destination without a start signal, as soon as the trunk is seized; the destination is specified during programming. Also called “automatic ringdown” or “auto-in” tie trunk.

auxiliary power unit Device that provides additional power to the system.

B

B8ZS

backup

(bipolar 8 zero substitution) Line-coding format that encodes a string of eight zeros in a unique binary sequence to detect bipolar violation. See also bipolar signal.

Procedure for saving a copy of system programming onto a floppy disk or memory card. See also restore.

bandwidth	Difference, expressed in hertz, between the highest and
	lowest frequencies in a range that determines channel
	capacity.
barrier code	Password used to limit access to the Remote Access
	feature of the system.
basic carrier	Hardware that holds and connects the processor, power
	supply, and up to five modules in the system. See also
	expansion carrier.
baud rate	Strictly speaking, a measurement of transmission speed
	equal to the number of signal level changes per second,
	In practice, often used synonymously with bit rate and
	bps.
B-channel	(Bearer-channel) 64-kbps channel that carries a variety of
	digital information streams, such as voice at 64 kbps, data
	at up to 64 kbps, wideband voice encoded at 64 kbps,
	and voice at less than 64 kbps, alone or combined.

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