User guide

G-10 Encore Multi-port DSU/CSU User GuideÑJuly, 1997
G
HDLC (High Level Data Link Control)
Bit-oriented, data-link control protocol; any related control of data links by
speciÞed series of bits, rather than by control characters.
I
IP address
A unique, 32-bit identiÞer for a TCP/IP host on a network. IP addresses are
normally printed in dotted decimal form, such as
L
LBO (Line Build Out)
An adjustable value used to tune the attenuation between the DSU/CSU card
and the last repeater on the T1 circuit.
LED (Light emitting diode)
A device that accepts electrical signals and converts the energy to a light
signal.
LOF (Loss of Frame)
Occurs when a received digital signal loses frame synchronization.
LOFC (Loss of Frame Count)
A count of declared Loss of Frame events (ESF framing only).
loopback
A diagnostic test in which the transmitted signal is returned to the sending
device after passing through a data communications link or network. This
allows a technician (or built-in diagnostic circuit) to compare the returned
signal with the transmitted signal and get some sense of what's wrong.
LOS (Loss of Signal)
Occurs when an input signal is detected as all zeros for 176 bit times.
loss
A reduction in signal strength, expressed in decibels.
LSC (Loopback Select Code)
An indicator describing a DSU loopback characteristic. LSC is a minimum of 35
LSC bytes of S11101F1 with secondary channel.