OSN1800V fiber optic transmission equipment TNF1ST2 single board belongs to the optical monitoring channel class of single boards, applied to achieve the east and west direction of the two-way optical monitoring signal transceiver control. Completion of the two optical monitoring channel signal receiving, sending control and processing. Support IEEE 1588v2 receive and transmit control and processing. Supports 2-way FE telecommunication signal transmission. Supports physical layer clock. Supports maximum 40.5dB cross-segment transmission. The optical monitoring channel does not limit the distance between two optical line amplifiers, and the failure of the line amplifiers does not affect the performance of the optical monitoring channel. The single board is independent of the main control board, i.e., when the main control board is not in position, it can still ensure that the ECC channels of the two pairs of optical ports on this board are automatically passed through to ensure the monitoring of other stations.

Problem Description

Version information: OSN8800V1R7C00 A FOADM site A under the same type of site B, in the completion of the project installation and fiber connection and docking found that site B in the U2000 can not complete the upload, prompting "the background is busy or the device is carrying out other operations, can not respond for the time being," in the site of A query ECC The ECC link at site A was found to be flashing off, and could not be stabilized;

OSC_LOS

NE_COMMUNICATION_FAIL

Processing

(1) The network element cannot be uploaded smoothly, focus on whether the ECC route is reachable;

(2) ECC channels include ESC,OSC, and you need to focus on troubleshooting OSC-LOS alarms;

(3) The network element can not complete the upload may also be because the network element is in the installation of non-normal operation state.

Root Cause

ST2 single-board optical module configuration error: Site A ST2 single-board TM1/RM1 port should have been configured with a 1511 nm optical module, the actual insertion of the optical module is a 1491 nm optical module, while the docking of the optical module at Site B is 1491 nm, and the actual receiving wavelength should be 1511 nm, and inconsistency in the docking wavelength leads to the reception of the OSC monitoring signals at Site B. Optical monitoring abnormalities at Site B result in disconnection. site optical monitoring anomalies lead to de-piping.

Solution

1, because it is a new project, so the line power needs to be verified; first of all, check the site B OAU receive optical power is normal, confirm that the site of the intermediate line part of the docking is not a problem, which can be determined to be the site of the internal problem;

2, first confirm the ECC flash off the problem:

(1) check the site ECC communication mode, found that the electric monitoring optical monitoring at the same time open, at this time the device defaults to the electric ESC priority (in the network management ECC can be viewed and verified), in order to facilitate the troubleshooting, the first optical monitoring OSC off (off the ST2 single-board lasers), from which you can find the ECC route of site B is still flashing off;

(2) to find the DCC management configuration of A network element, view the DCC resources and communication status, found that a number of OTN single-board DCC reception failure, shut down the other OUT single-board ESC channel to retain a piece of the OUT single-board ESC enable found that the ECC route of the site B is still blinking off;

(3) At this point, the suspicion that the site B OUT single board ESC channel conflict, so the next station to the site B, the scene with the U2000 directly connected to the device, found that all the OUT single board are not added to the logical board settings. OUT single board to add a logical single board, at this time you can find that the ESC link no longer flash off. R & D staff analyzed the ESC flash off because the ESC information in the wavelength of the OTU board has been added and the ESC conflict with the uncreated logical single board.

3, followed by the next step in the investigation of the OSC channel, at this time the ESC has been normal, found that the B station has OSC_LOS alarm.

4, view the A site ST2 single board TM1, RM1 pigtail optical power were: -2, -8dBm, can have to monitor the channel to receive light; but the B station OSC receiving light is not normal, the suspicion is that the B site ST2 single board RM2 port pigtail connection reverse;

5, the next station to the B site, the ST2 board RM2/TM2 optical port pigtail swap, the alarm still exists; so you can rule out the cause of the tail fiber connection reversal, and then do SFIU and tail fiber replacement, found that the fault still exists;

6, so the last suspected ST2 single-board optical module failure: in accordance with the design of the original diagram to check the ST2 single-board optical module, found that the B site ST2 single-board optical module configuration is normal, TM1/RM1 port configuration 1511 nm optical module, TM2/RM2 configuration 1491 nm optical module, to confirm that it is normal; after checking the A site ST2 single-board optical module configuration, found that TM1/RM1 and TM2/RM2 port are configured with 1491 nm optical module, and then the ST2 single-board optical module configuration. After checking the configuration of ST2 single board optical module at site A, it is found that TM1/RM1 and TM2/RM2 ports are configured with 1491 nm optical modules, which is an error in the configuration of optical modules;

7. Finally, it can be concluded that the root cause of the optical monitoring channel anomaly at station B is that the ST2 single board TM1/RM1 port at station A should have been configured with a 1511 nm optical module, and the actual insertion of the optical module is a 1491 nm optical module, while the docking of the optical module at station B is a 1491 nm optical module, and the actual wavelength of the receiving wavelength should be 1511 nm, which is not the same as the docking wavelength and leads to an abnormal optical power of the OSC monitoring signal at station B, thus making the optical monitoring signal at station B anomaly. The inconsistency of the docking wavelength leads to abnormal optical power at site B receiving the OSC monitoring signal, which results in abnormal optical monitoring at site B leading to de-piping.

Finally, the ST2 single board TM1/RM1 port optical module at site A is replaced and configured as 1511nm type, and the network elements at site B are monitored normally. Troubleshooting.

Recommendations and Summary

1, ST2 single board and SIFU used in conjunction, in order to realize the 1588v2 function, in the line side of the implementation of the Line1 channel of the single-fiber bidirectional monitoring signal transmission;

2, ST2 single board TM1/RM1 port send and receive optical wavelength is actually two wavelengths, upstream and downstream site OSC wavelengths should be realized TM1/RM1 port - TM2/RM2 port docking, to maintain the same send and receive OSC wavelength;

3, SFIU single-board Line1 optical port design from the above chart can be found, both business signals + monitoring signal output port, can also be the downstream site of the signal input docking port, which is often in the project to connect the fiber to the wrong lead to the optical path is blocked;

Recommendation:

1, in the construction of the project, meet the new characteristics of the veneer must be strictly in accordance with the original design drawings with fiber, found in doubt to the designers to confirm in a timely manner, not in accordance with conventional habits of their own operations;

2, in the equipment shipment before installation and testing, should check whether the shipment configuration and design configuration to maintain consistency;

3, the equipment can not complete the upload should focus on the ECC link information, focusing on verification of ESC and OSC channel smooth;

The relevant technical information in this chapter and the SDH equipment troubleshooting process are collected and organized by Shenzhen Optical Transmission Network Technology Company Limited (www.opticaltrans.com), please retain! Our company specializes in Huawei SDH optical transmission equipment,SDH transmission equipment sales.