1. there is a fiber cut in the ASON domain NEs.
2.if there was a fiber cut in the working path, so traffic (VC4 trail) should switch to some other existing path.
3. trail took the other path but it was not able to use those resources as it was not shown in the TE link management, even though the SF64 in power was -3 dbm to -4 dbm.(there were 5 SF64 cards in a section of ASON NEs, but none of them was shown in the ASON TE link management).
1. because of the point no. 4 in the "Phenomenon description" the trail taking this path was down and was showing the interrupted alarm( i.e the trails taking this paths were interrupted)
1. we had reduced the gain of the amplifiers in that section in both the directions.
2. and after reducing the gain Obviously the input power at the SF64 in port was also reduced and now they were receiving the normal input power, i.e. -8 dbm around in each SF64 card.
3. after doing this we checked the TE links in ASON TE links management. and we found that it is showing the TE links there also.
1. when we checked the input power for the Channels which should be there in the ASON TE link management, then we found that they all were getting around -3 dbm to -4 dbm input power.
2. The analysis is as follows:
earlier the section loss between the DWDM NEs was very high, so for compensating that loss we increased the gain of the amplifier in both the directions so that the
channel should receive proper input power at ite INPUT ports,
but after some time the fiber loss was improved by 5-6 dB as customer has taken the outage on the fiber and rectified and improved the fiber losses by 6 db around, but after the loss is improved and the still amplifier
gain was set to very high as a result of this the OTU (SF64 cards in this case) connected in this direction were receiving the high input power at their input.
1. if any SF64 card is connected in the network then its standard input power should be around -8 dbm as per our standard.
2. if we increase the gain in the high fiber loss condition then after the loss rectification we should reduce the gain to the appropriate value and also we need to do
the recommissioning of the whole link in which the loss is improved.
3. and also need to check the ASON TE link Immediately after the commissioning, so that in the fiber cut condition the trail can take or can use the resources in all