Table of Contents
Advertisement
DIDCSU T1 Version
Command
Ln
Line Coding: Use this option to choose Alternate Mark Inversion (AMI) or
Bipolar Eight-Zero Substitution (B8ZS), as required by the type of your T1
facility.
B8ZS enables each DS0 to transmit at 64 kbit/s with unlimited zeros. This
option overrides any selected network density enforcement.
AMI is the original T1 line format that does not support long strings of
zeros. Normally, this option is used in conjunction with the network density
enforcement option.
Bn
Line Build Out: Line build-out is used to reduce the transmit signal
amplitude of the CSU.
0 db: if the repeater is between 2000 and 3000 feet from the CSU, or if you
are using a network termination device (smart jack) used by most phone
companies (most common setting).
• -7.5 db: if the repeater is between 1000 and 1999 feet from the CSU.
• -15 db: if the repeater is between 250 and 999 feet from the CSU.
• -22.5 db: if the repeater is between 0 and 249 feet from the CSU.
NDn
Network Density: Use this option to specify the type of network density
enforcement. Digital transmissions over public switched telephone network
lines cannot support long strings of zeros (repeaters and clocking devices
lose synchronization). Therefore, the density algorithms ensure that a
minimum pulse density is met to ensure stable system timing.
Choose one of the following if using 56K AMI. Note that these options are
ignored by B8ZS line code:
• None: does not insert a one. Use this option with B8ZS.
• 80 Zeros: inserts a one into every string of more than 80 consecutive
zeros.
• 15 Zeros: inserts a one into every string of more than 15 consecutive
zeros.
• 12.5% & 80 Zeros: inserts a one into every string of eight or more
consecutive zeros when the average density of ones falls below 12.5% or
if there are more than 80 consecutive zeros.
• TR 62411: inserts a one into every string of more than 15 consecutive
zeros, or when there are less than a minimum number of N ones in every
window of 8(N+1) data bits (12.5%). N can be any value from 1 to 23. This
option is the same as 12.5% + 15 zeros.
NLn
Network Initiated Loop: Use this option to specify if you wish to allow the far
end or telco to put your DIDCSU in a loopback. (Usually Yes)
An
Alarm Declare Time (sec): Use this option to indicate how many seconds will
elapse before a message regarding a problem is displayed.
DLn
FDL Enable/PRM Enable: Facilities Data Link (FDL). The ESF Facilities Data
Link is used to transmit performance information, error events, and
loopback controls. FDL uses 4 kbit/s of the 8K framing bandwidth on an ESF
T1 to transmit messages. This option only enables or disables FDL. The
Performance Report Message Command/Response (PRM C/R) displayed with
this option shows the current status of the PRM C/R bit. To change this
option, use F (FDL Configuration) and select Cn (PRM C/R bit). Enabling FDL
is meaningless for ports connected to an SF-framed T1.
3-8
Description
Verilink DIDCSU 2912 User Manual
Options
1) AMI
2) B8ZS
1) 0db
2) -7.5db
3) -15db
4) -22.5db
1) NONE
2) 80 zeros
3) 15 zeros
4) 12.5% 80
zeros
5) TR 62411
Yes or No
(Y/N)
0...127
seconds
Yes or No
(Y/N)
Advertisement
Table of Contents
