SDH : Acceptable NSE + NEWPTR events ?

mchemsi28 · ‎03-15-2008

Hello everybody,

I experience an increasing number of SDH NSE + NEWPTR events, about 40 event/second.

I have a 7200 VXR router with a PA-POS-1OC3 card (STM-1), connected through an SDH network to another router. Both routers clock source are set to "line".

We performed loop tests in our carrier ADMs starting from the closest to Router, and there were no errors through 4 ADMs. In the fifth there were NSE, PSE and NEWPTR events.

Until now there were no dramatic traffic degradation (except one time where the ping success went to 85%, but I don't know if these errors was the cause).

Do this events rate cause traffic degradation ?

Thanks in advance.

htarra · ‎03-21-2008

If the SDH interface of the router is directly connected to an SDH ADM (i.e. there is no regenerator in between), it should be synchronised to the SDH network. This can be provided by the "clock source line" interface configuration command.

FEBE (far end block eror) is the old name for MS-REI (SDH term) or REI-L (Sonet term). It is the count of the line BIP errors reported by the far end, in this case the SDH ADM. The source of errors can be faulty or contaminated optical connectors, faulty interfaces, etc. It is best to troubleshoot by setting physical loopback at various points of the optical path.

NEWPTR is the counter of events the SDH framer of the line card received a new pointer value in the SDH line overhead H1 and H2 bytes. NSE is the same for negative stuffing events. These events usually indicate improper clock setting somewhere in the SDH network.