Paradyne 3910 Automatic dial backup, Automatic dial standby, Automatic rate control, Backplane

COMSPHERE 3900 Series Modems

automatic dial backup	When leased-line operation fails, this function forces the modem to
	dial the telephone number stored in directory location 1.
automatic dial standby	When operating in Dial Backup mode, this function forces the
	modem to periodically check the quality of the leased line. If the
	leased line is found to be at normal operating condition, the
	modem disconnects from the dial network and continues normal
	operation over the leased-line network.
automatic rate control	Modems adjust their signaling rate based on current line
	conditions.
backbone network	The primary route from a control modem to its first tributary when
	the communications network contains extended control modems.
backplane	A common bus at the rear of the COMSPHERE 3000 Series
	Carrier connecting each circuit card slot to the SDCP and/or SDU.
	It also distributes low-voltage ac power to each slot.
baud	A unit of signaling speed that is equal to the number of symbols
	per second. This is not necessarily the same as bits per second,
	although the terms are frequently interchanged.
Bisync	Binary Synchronous Communications. An IBMr
	communications protocol that has become an industry standard. It
	uses a defined set of control characters and control-character
	sequences for synchronized transmission of binary-coded data
	between stations in a data communications system.
bit	A contraction of binary digit. A bit, which is the smallest unit of
	information, represents the choice between a one or a zero
	(sometimes called mark or space).
bps	Bits per second. Indicates the speed at which bits are transmitted
	across a data connection.
broadcast	A method of transmission. The simultaneous transmission to two
	or more communicating devices.
buffer	A storage device used to compensate for differences in the data
	flow rate when transmitting data from one device to another.
byte	A sequence of successive bits (usually eight) handled as a unit in
	data transmission.
carrier	The rack mounting that contains 17 slots: 1 control slot for an SDU
	and 16 modem slots. See data carrier.
carrier-mount	A modem that is designed for installation in a COMSPHEREr
	3000 Series Carrier and used at central-site operations.

GL-2 November 1996 3910-A2-GN32-30