Nortel Networks 3500, NTRN10AN manual Node status ’Bridged and Switched’

Operation, administration, and maintenance (OAM) features 2-15

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Step Action

6Node 4 receives the message on the long path, and enters into a ‘Bridged’ state. Node 4 bridges traffic from the incoming working channels to the opposite direction, outgoing protection channels. Node 4 acknowledges receipt of the message by sending a ‘Bridged’ message back to Node 3 on the Long Path.

•source node (Node 4)

•destination node (Node 3)

•type of switch request (Signal Degrade)

•path direction (Long)

•node status (’Bridged’)

Note: Nodes 1 and 2 remain in the ‘Passthrough’ state.

7Node 3 receives the ‘Signal Degrade’ request from Node 4, and enters into a ‘Bridged’ state. Node 3 bridges traffic from the working to the protection channels and acknowledges receipt of the message by sending a ‘Bridged’ message back to Node 4 on the Long Path.

•source node (Node 3)

•destination node (Node 4)

•type of switch request (Signal Degrade)

•path direction (Long)

•node status (’Bridged’)

8Node 4 receives the ‘Bridged’ status indication from Node 3. Node 4 enters into the ‘Bridged and Switched’ state. Traffic received on the protection channels are then routed as if they were received from the failed working link. Node 4 then sends a message to Node 3 indicating that it has entered into the ‘Bridged and Switched’ state.

•source node (Node 4)

•destination node (Node 3)

•type of switch request (Signal Degrade)

•path direction (Long)

•node status (’Bridged and Switched’)

Note: Depending on the cross-connects provisioned, Node 4 will then either drop traffic at the add/drop multiplexer or route traffic back out onto the working channels of the ring.

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Planning and Ordering Guide—Part 1 of 2 NTRN10AN Rel 12.1 Standard Iss 1 Apr 2004