No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>


To have a better experience, please upgrade your IE browser.


Lost of managament when is inserted a new OSN7500 with SF64 boards due to incorrect Overhead mode

Publication Date:  2012-07-25 Views:  79 Downloads:  0
Issue Description
The idea of the project is to insert a new OSN 7500 in the capital ring in nodes where are OSN 3500 . the OSN3500 will be connected to the OSN 7500 as tributary nodes.
the next picture shows the state of the NEs before the insertion of the OSN 7500.

an after the insertion of the OSN 7500:

the OSN 7500 is connected to a metro 6100 that is configured as oadm with mr2 boards. the OSN 7500 have sf64 boards. at the remote end there are a OSN 9500 with boards SF64D.
during the insertion of a osn 7500, after all the fibers connections were made between the osn 7500 and osn 3500 and between the osn 7500(sf64 boards) and metro 6100(mr2 boards), the people at the noc( in management with T2000-remote) were no able to login the new osn 7500 and the osn 3500 now configured as tributary node.

Alarm Information
  • 1) the lost of management at the noc-remote
    2) after we went over the fiber connections and the state of the fibers we find out that were ok.

Handling Process
first we check on site the configuration of the overhead mode of the cards. this could be made in two ways:
1)with navigator:
where bid is the slot of the sf64 board and pid is the port. for example for our case one of the sf64 board we get the next.
oh mode
bid pid ohmode
5 1 gcc
2) with t2000
In the next print screen could be checked the overhead mode that is configured:

1) With navigator:
:cfg-set-ohmode:14, 1,dcc;

the we check again the Overhead mode:
oh mode
bid pid ohmode
14 1 dcc
with this the login to the OSN was successful.

2)with t2000( we use t2000 v2r7c03)
we should choose DCC mode and then click at the botton Apply.

Root Cause
the SF64 board support two overhead transfer modes: gcc and dcc. in case of gcc, the ecc overheads are extracted by the fec chip and then sent to the fpga chip. the processed overheads signal is transported to the working and standby scc boards and the corresponding board at the other end by means of the 16 mbit/s overheads bus. in case of dcc, the ecc overheads are processed by the sdh chip.
the dcc mode supports sdh communication and gcc supports wdm communication.
the board has configured by default the gcc mode.
when the osn 7500 (with SF64 boards) connects to other ng-sdh equipment via dwdm(metro 6100), the overhead modes on both sides should be the same. hence the overhead mode should be dcc.

this must be made always when a fixed wavelength board is installed in a network like the SF64, SF16