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Super Bronze

G703 and PRI Clocking on same ISR


Does anyone know how to cleanly clock two seperate interfaces on the same ISR?

Specifically I'm talking about a 2800 with a VWIC-1MFT-E1/T1 and a VWIC-1MFT-G703. I've set the network-clock-participate on each WIC and network-clocks-select on the E1 primarily, and the G703 secondarily.

This results in no slips on the E1, but some slips on the G703 interface... This works OK, with a clean voice interface but will result in some retransmissions (I guess) on the data circuit.

Is there a way for both circuits to take clocking from their two seperate sources (in this case WAN and PSTN service providers)? I presume as nothing will be directly TDM switched between the two interfaces they don't need to be synchonised to each other?

I suspect the answer will be simple ('No', or just don't set network-clock-participate/select on one interface?) but aren't in a position to try it now and can't see any clear examples on



Responses will be rated..

Aaron Please remember to rate helpful posts to identify useful responses, and mark 'Answered' if appropriate!
Hall of Fame Super Gold

Re: G703 and PRI Clocking on same ISR

Hi Aaron,

you are correct in saying that because there is no TDM switching the importance of clock synchronization is secondary, and probably you have already set everything correctly.

If you doubt that the data circuit may be carrying errors, just look at the counters at interface level. Slips and other L1 problem will reflect there as CRC, shorts, and other errors.

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