[c-nsp] experiences or success stories related to XENPAK-10GB-ZR

[Dale W. Carder]

On Jul 5, 2007, at 6:58 AM, Emanuel Popa wrote:
> now, examining the business case we would like to go further with the
> second solution: tengigabit directly over the fiber. the problem is
> that the distance between different points of presence is somewhere
> between 50 - 80 km. the only XENPAK that can offer connectivity over
> this distance is the XENPAK-10GB-ZR:
> http://www.cisco.com/en/US/customer/products/hw/modules/ps4835/ 
> products_data_sheet09186a008007cd00.html

Do you know the exact type of fiber you're on or has it been measured
for attenuation, ORL, and dispersion?  You probably want to know
at least those parameters before proceeding, particularly for the
longer spans.  Also, since you don't have any FEC on the xenpak,
leave yourself some headroom.

The ZR xenpak says it will tolerate up to 1600 ps/nm with a 3dB penalty.
If so, that could be really cool, because worst-case hopefully you
won't see much worse than 18 ps/nm/km.

I mention optical return loss because if you are going through a lot
of jumpers/patch panels to get to your metro fiber you could get
burned (and all you will see on your 7600 is link-flap errdisable).
Use only quality -40dB ORL or better jumpers.

Dale