Verilink Access Manager 2000 (896-502037-001) Product Manual - Manual (Page 344)

A-12 Access Manager 2000 Manual
Line Loopback An LLB is a loop which takes the signal from the DS-1 network and
loops it back toward the network. The loop does not allow the DS-1
signal to pass through the CSU (except for critical protection circuitry
and the repeater), making it useful for testing the DS-1 line.
LLB See Line Loopback.
Local Area Network A type of high-speed data communications connection where all
segments of the transmission medium are in the office.
LOF See Loss-of-Frame.
LOFS See Loss-of-Frame Second.
Login To log in to a computer is to establish a connection through an input
device to identify yourself as an authorized user.
Loopback A method of checking the accuracy of a data transmission in which the
transmitted data is looped back to its source for comparison.
Loopbacks may be initiated from various point along the circuit.
LOS See Loss-of-Signal.
Loss-of-Frame Loss-of-Frame alarm is declared when a 3-second interval of
continuous Out-Of-Frame (OOF) or Loss-Of-Signal (LOS) state is
detected. An LOF alarm is cleared when at least 10 seconds of
continuous non-LOS or non-LOF condition exists.
Loss-of-Frame Count An accumulation of the number of times a Loss-Of-Frame alarm is
declared.
Loss-of-Frame
Second LOFS is the total number of seconds that the CSU was in the LOS
state.
Loss-of-Signal The state of a T1 line when no bits are detected on input to the
receiving equipment. The time for detection of loss of signal will vary
depending on the type of equipment used. The Loss-Of-Signal state is
then integrated into a LOS alarm after 3 seconds of continuous
Loss-Of-Signal state.
Loss-of-Signal
Second A second during which the CSU is in a Loss of Signal state. These
seconds are recorded by the NCCs and TACs in Access System 2000
nodes.
Term Definition