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Cisco ONS 15310-CL, ONS 15310-MA, and ONS 15310-MA SDH Ethernet Card Software Feature and Configuration Guide, R9.1 and R9.2
78-19415-01
Chapter 17 CE-Series Ethernet Cards
CE-MR-6 Ethernet Card
Figure 17-8 End-to-End Ethernet Link Integrity Support
Note
Some network devices can be configured to ignore a loss of carrier condition. If a device configured to
ignore a loss of carrier condition attaches to a CE-MR-6 card at one end, alternative techniques (such as
use of Layer 2 or Layer 3 keep-alive messages) are required to route traffic around failures. The response
time of such alternate techniques is typically much longer than techniques that use link state as
indications of an error condition.
In certain network configurations, the restoration time, for example, after a protection switch can be
more than 200 ms. Such disruptions necessitate the link integrity to be initiated at an interval greater than
200 ms. To allow link integrity to be initiated at an interval greater than 200 ms, set the link integrity
timer in the range between 200 and 10000 ms, in multiples of 100 m s.
Note
The accuracy of the Link Integrity timer is less on CE-MR-6 card compared to the G1000 or CE-1000
cards. The accuracy of Link Integrity timer is within 200 ms for the CE-MR-6 card.
Ethernet Drop and Continue Circuit
The CE-MR-6 card supports Ethernet drop and continue in CCAT circuits. Ethernet drop and continue
(unidirectional) circuits have multiple destinations for use in broadcast circuit schemes. In broadcast
scenarios, one source transmits traffic to multiple destinations, but traffic is not returned to the source.
Figure 17-9 Unidirectional Drop from a CE-MR-6 card on Node 1 to Nodes 2, 3, and 4
ONS Node
Ethernet port
115780
Tx
Rx
ONS Node
Ethernet port
Tx
Rx
STS-N
SONET
Unidirectional Unidirectional
Unidirectional
circuit
Drop Drop Drop
CE-MR-6
(source)
Node 1
ONS 15310
Node 2
ONS 15310
Node 3
ONS 15310
Node 4
ONS 15310
253038
CE-MR-6 CE-MR-6 CE-MR-6
Unidirectional
Unidirectional
Unidirectional