Alcatel-Lucent 9500 MXC, User Manual, Page: 872 / 916

Vol. VI-F-16 Alcatel-Lucent
Figure F-7.
Pass-through, Drop and Wrapping Action
Tx
Rx
West-facing RAC/ODU East-facing RAC/ODU
TDM Bus
DAC Tx Rx
ODU
ODU
Rx Tx
Primary Rx
Secondary Tx
Primary Tx
Secondary Rx
Primary ring with pass-
through and drop traffic
Secondary ring carries
no traffic
Primary ring wrapped to
secondary at Node C
Secondary ring wrapped
to primary at Node D
Normal condition
Primary ring wrapped
to secondary at Node B
Secondary ring wrapped
to primary at Node C
No break No break
No break
No break
Break
Node C
Node D
Break
Node B
Node B
Break between Nodes C & D
Break between Nodes B & C
Pass-through traffic
Add-drop traffic
Primary
Secondary not used
Secondary used
Node C Node D
Rx
Rx
Rx
Tx
Tx
Tx
Local add
Local drop
Pass-through circuits