POS Clock options on a 12000 GSR

[nitinkhan]

Hi all,

What are the clocking options for a POS Line card or Port on a Cisco 12008 GSR.

1) Internal

2) Line

3) Sysclock???

4) BITS ???

How can I configure the sysclock?? IOS Commands??

Thanks

Nitin

[dwyerr]

Hello,

Internal and line are the only options I am aware of. The router does not provide a sonet clock generator.

I also think it is a good practice to enable scrambling of the signal, "pos scramble-atm", to help with clocking.

Regards.

-Rob

[nitinkhan]

Thanks Rob,

Hardware description of GSR mentions Clock, scheduler card CSC as well. And if you scour the cisco website, there is information about BITS clock configuration on GSR 12416, that supplies Startum 1 clock to all the slots on GSR. If I set the POS interface to Line on my end and GSR line as well, we see a lot of NEWPTR and NSE's. If GSR is let to Internal samething happens.I have also tried Int-Int combination as well, nothing seems to work.

I have a 7304, IOS Rel 12.1E. 1 port OC-3 POS card.

Any more ideas?

Thanks

[dwyerr]

The CSC card has nothing to do with timing on the line. The clocking it provides is internal to the RP and other cards. It provides the cross connects, "cross bar", between cards and is responsible for managing access to the switch fabric. It also provides some alarm functions.

In terms of the 12416 I have not seen a bits clock for the GSR at all, regardless of cage type. It is possible though that the new Engine 4 cards may provide this function, I was not able to find any such feature glancing at the documentation though.

Finally, I have seen the issue with NEWPTR and NSEs and these are indeed caused by clock slips.(Usually when there is a large distance between both ends or you have different vendors on each side of the link.) In my experience changing clocking to line usually resolves it. (This of course assumes the provider is putting clock on the line.)

-Rob

[nitinkhan]

Rob,

Take a look at following document

http://www.cisco.com/en/US/products/sw/iosswrel/ps1829/products_feature_guide09186a008042e07e.html

Let me know what your thoughts are.

[dwyerr]

Pretty cool!

Need a 12816 or 12810 though and engine 6s :-(

A cool feature though. It also explains the T1 controllers on my PRP2s :-)

-Rob