27 — Loopbacks
27-6
2902 MainStreet Technical Practices
90-2906-01 May
2002
Procedure 27-3 To set a 2B1Q circuit loopback
where
pp
is 1 or 9, and
c
is A or B
27.3
DNIC circuit loopbacks
DNIC modules support remote connection of data devices through 2600 MainStreet
series DTUs.
For 2602 and 2603 MainStreet DTUs that support super-rate, super-rate circuit
loopbacks can only be applied while the circuit is connected. If a loopback is applied
to either port while neither is connected, the system displays the following error
message: “Connect super-rate circuit before applying loopbacks.” If a loopback is
applied to one port while the other is involved in a super-rate connection, the system
displays the following error message: “Loopback invalid: other port involved in
super-rate connection.”
Loopback A for two-port DTUs
For two-port DTUs, loopback A occurs on both lines (Port A and Port B)
simultaneously (see Figure 27-5). Loopback A extends from the DX on the Control
card and loops back on the DNIC line driver located on the DNIC module.
UNDO_MAINT
ON_CIRCUIT
<
pp-c
>
↵
LOOPBACK_A
LOOPBACK_E
LOOPBACK_B
UNDO_LPK
MAINT
SK000541
Summary of Contents for MainStreet 2902
Page 1: ...2902 MainStreet Network Termination Unit Release 1 0 H T E C H N I C A L P R A C T I C E S ...
Page 40: ...3 Mounting the unit 3 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 50: ...4 Ground and power connections 4 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 68: ...6 Connecting to the network 6 4 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 90: ...7 Connecting to data devices 7 22 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 108: ...10 Node management 10 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 150: ...14 CPSS 14 6 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 218: ...20 Codirectional DCM 20 6 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 234: ...22 HCM rate adaption 22 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 246: ...23 Cross connecting circuits 23 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 254: ...24 Visual indicators 24 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 266: ...25 Alarms 25 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 278: ...26 System diagnostics 26 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 298: ...27 Loopbacks 27 20 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 332: ...Glossary GL 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 343: ......
Page 344: ... 2002 Alcatel All rights reserved 90 2906 01 95 1820 01 00 C ...