Cable length option, used to increase DSX-
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
1 signal strength when DSX-1 cable is long.
length of the cable between the CSU and the local DSX-1 equipment.
Line build out is used to reduce the signal strength being sent to the T1 network.
(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.
New T1 circuits installed by a telephone company in the USA will have a smart jack—use 0db.
(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.
(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.
The value “none” should not be used on a commercial T1 circuit as it violates T1 standards (AT&T 54016 and ANSI T1.403).
(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.
disable — Alarm threshold function is shut off.
default — Default values for alarm thresholds are
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.
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.
Verilink NCC 2020 User Manual