Figure 29. Loopback Block Diagrams - ADTRAN DS3 NIU3 PM Installation And Maintenance Practice

Ntwk In
I
Ntwk Out
RCV LOS
Dectector
Ntwk In
Ntwk LOS
Indication
II
Ntwk Out
Customer
Network
Monitor
Ntwk In
Ntwk LOS
Indication
III
Ntwk Out
Customer
RCV LOS
Detector
Ntwk In
Ntwk LOS
Indication
IV
Ntwk Out
Regen.
Customer
To
Network
Monitor
61213075L2-5E
Network to customer bypass
AIS
RCV LOS
Detector Detector
Ntwk AIS
Ntwk LOS
Indication
Indication
Customer to network bypass
Regen.
RCV Framing
Detector
Customer C-Bit/M13
Indication
Customer
To
Network
Normal Operation Showing Bypass and Relays
Monitor
AIS RCV Framing
Detector
Ntwk AIS
Ntwk C-Bit/M13
Indication
Indication
RCV Framing
Detector Detector
Regen.
Customer C-Bit/M13
Customer AIS
Indication
Indication
To
Network Loopback
AIS RCV Framing
RCV LOS
Detector Detector
Ntwk AIS
Ntwk C-Bit/M13
Indication
Idle Code
Generator
Regen.
Cust C-Bit/M13
To
Customer Loopback
Network
Monitor
AIS RCV Framing
Detector Detector
Ntwk AIS
Ntwk C-Bit/M13
Indication
Indication
Dual Loopback

Figure 29. Loopback Block Diagrams

Issue 5, February 2011
Regen.
RCV Framing
Detector
Ntwk C-Bit/M13
Indication
Network
To
Customer
Monitor
AIS RCV LOS
Detector Detector
Customer AIS
Customer LOS
Indication
Indication
Regen.
Detector
AIS RCV LOS
Detector
Customer LOS
Indication
Detector
Indication
RCV Framing
AIS
Detector
Detector
Customer LOS
Customer AIS
Indication
Indication
RCV Framing
Detector
Detector
Customer AIS
Cust C-Bit/M13
Indication
Indication
Cust Out
Cust In
Cust Out
Network
To
Customer
Monitor
Cust In
Regen.
Cust Out
Network
To
Customer
Monitor
RCV LOS
Detector
Cust In
Indication
Regen.
Cust Out
Network
To
Customer
Monitor
AIS RCV LOS
Detector
Cust In
Customer LOS
Indication
27