Verilink NCC 2020 (880-503284-001) Product Manual - Manual (Page 28)

Configuration
3-6 Verilink NCC 2020 User Manual
M) distance Cable length option,
used to increase DSX-
1 signal strength
when DSX-1 cable is
long.
Choices are: (1)0-133 (2)133-266 (3)266-399 (4)399-533
(5)533-655 — Select the value that most nearly equals the
length of the cable between the CSU and the local DSX-1
equipment.
L) lbo Line build out is used
to reduce the signal
strength being sent
to the T1 network.
New T1 circuits
installed by a
telephone company
in the USA will have a
smart jack—use 0db.
(1) 0 db — use this value if a smart jack (network
termination device) has been installed by the telephone
carrier, or if the first active device on the T1 is between
2,000 and 3,000 feet away.
(2) 7.5 db — use this value only if there is no smart jack and
the first repeater is 1,000 to 2,000 feet away.
(3) 15 db — use this value only if there is no smart jack and
the first repeater is zero to 1,000 feet away.
K) keep alive Selects the method
used to guarantee
sufficient pulse
density is sent to the
T1 when the DSX-1
equipment has failed
or is disconnected.
The value “none”
should not be used
on a commercial T1
circuit as it violates
T1 standards (AT&T
54016 and ANSI
T1.403).
(1)none — no method of keep alive is used in the absence of
a valid, framed DSX-1 signal. Do not use this value on a T1
circuit provided by a telephone company.
(2)loop — when the DSX-1 signal fails, the CSU loops data
received from the T1 back toward the T1 to meet pulse
density requirements.
(3)ais — the CSU sends a pattern of unframed all ones
(Alarm Indication Signal) to the network during a DSX-1
equipment failure, thus alerting the carrier and far-end
equipment to trouble on the T1.
(4)fais — the CSU sends a framed pattern of all ones. This
should not create a T1 level alarm, but voice switching
equipment will see all 24 timeslots in a busy state.
T) alm thld Selects enabling or
disabling thresholds.
(1)disable — Alarm threshold function is shut off.
(2)default — Default values for alarm thresholds are
enabled.
I) idle code Selects idle pattern to
be sent in 4K FDL,
used for ESF circuits
only, no effect on SF.
1(flag's) — idle code of 01111110 is sent in Facilities Data
Link when no other traffic is present.
2(one's) — idle code of 11111111 is sent in Facilities Data
Link when no other traffic is present.
Z) density Selects density
enforcement
technique.
Density should
always be set to
NONE on a B8ZS T1,
B8ZS allows a full
64K per DS0.
Density should never
be set to NONE on an
AMI T1.
(1)NONE — no density enforcement, use this value only and
always on a B8ZS T1.
(2)12 — The CSU begins stuffing ones into the user
datastream after 12 consecutive zeroes.
(3)62411— The CSU enforces AT&T publication 62411
density restrictions (average 12.5% minimum ones density).
(4)80 0's — The CSU begins stuffing ones into the user
datastream after 80 consecutive zeroes (recommended).
(5)15 0's — The CSU begins stuffing ones into the user
datastream after 15 consecutive zeroes.
Menu Option Description Instructions