Paradyne 3551 manual Ldm

COMSPHERE 3550 Series Data Service Units

errored second	A performance measurement reported during Digital Test or Transmit Test Pattern
	that is defined as a second in which at least one error has been detected.
facility alarm	A failure condition reported to the 6700 Series NMS when there is a break in
	communication with one or more tributary.
fallback	Retraining of a V.32 DBM at a lower rate or speed.
FCC	Federal Communications Commission. Board of commissioners that regulates all
	interstate and foreign electrical communication systems that originate from the
	United States.
Front-End Processor	A communications computer associated with a host computer that manages the
(FEP)	lines and routing of data through the network; it is the data terminal equipment
	(DTE) at the control DSU.
generator	A circuit in a DSU or in external test equipment that produces a continuous string
	or stream of known data patterns.
IEC	InterExchange Carrier. A company that provides inter-LATA (local exchange
	carrier) telecommunication services, like AT&T, MCIr, and Sprintr. Access to
	these services can be provided through DDS dedicated channels, T1.5 dedicated
	access channel, or digital switched access (DSA) channels.
LADS	Local Area Data Set (also called a limited-distance modem or LDM). This refers to
	a mode of operation where the control and tributary DSUs are directly connected
	but not passing through a DDS network.
Lamp Test	A test to verify that all status indicators and the control panel's LCD are operating.
LATA	Local Area Transport Area. A region served by a local exchange carrier (LEC) that
	consists of one or more area codes.
LCD	Liquid Crystal Display. A thin sandwich of two sealed glass plates containing liquid
	crystal material. When voltage is applied, the amount of light able to pass through
	the glass plates is altered so that messages may be ªwrittenº on the display.
LDM	Limited-Distance Modem (also called a local area data set or LADS).
LEC	Local Exchange Carrier. A company that provides intra-LATA (local exchange
	carrier) telecommunication services, like NYNEX or Bell South.
LED	Light-Emitting Diode. A light or status indicator on the diagnostic control panel
	(DCP) that glows in response to the presence of a certain condition (e.g., Alrm).
link-level address	NMS communications are directed to a tributary via a link-level address. It takes
	the form of control network address/tributary network address (e.g., 157/04 ± DSU
	control address of 157 and tributary address of 04).
Local Loopback	A test used to determine whether the DSU's DTE connection and the DSU are
	operating properly. The DSU must be connected to the DTE for this loopback to be
	run.
LSD	The state of the received Line Signal Detect lead, also known as carrier detect.

Glossary-4 December 1996 3550-A2-GB20-20