Alcatel-Lucent 7450 - Figure 20: Failed Condition; Figure 21: Failed Condition - Switching at a

MPLS-TP Maintenance Identifiers
Page 78 7450 ESS MPLS Guide
Figure 20: Failed Condition
In normal condition, user data packets are sent on the working path on both directions, from A to Z
and Z to A.
A defect in the direction of transmission from node Z to node A impacts the working connection
Z-to-A, and initiates the detection of a defect at the node A.
Figure 21: Failed Condition - Switching at A
al_0234
A
Working
Selector
Bridge
Selector
Protection
Z
Working
Selector
Bridge
Selector
Detected Alarm
Protection
al_0235
A
Working
Selector
Bridge
Selector
Protection
1
1
APS-1
Z
Working
Selector
Bridge
Selector
Protection