RE: 100G, input errors and/or transceiver issues

[Kevin Menzel via NANOG <nanog () nanog org>]

Hey Graham,



We're running 6xDWDM PAM4 100G links currently (for approx. 24 months) - I just pulled up our 13 month statistics, and 
we've had less than 100 input errors across every link total across that time period.



Every single input error seems to correspond to a fibre cut/flap - I've seen an unprecedented 11 input errors total 
this month on one link. I'd note that “post covid economic reopening” has meant “run lots of construction equipment 
through fibre optic cables” and that's caused us more issues than any optic or interface has.



For reference, we're a Cisco/SmartOptics shop, and our links aren't super long distance - ~40-60km, nothing that would 
require coherent optics.



  *   Kevin Menzel

On July 19, 2021 13:19, Graham Johnston <johnston.grahamj () gmail com<mailto:johnston.grahamj () gmail com>> wrote:

Saku,

I don't at this point have long term data collection compiled for the issues that we've faced. That said, we have two 
100G transport links that have a regular background level of input errors at ranges that hover between 0.00055 to 
0.00383 PPS on one link, and none to 0.00135 PPS (that jumped to 0.03943 PPS over the weekend). The range is often 
directionally associated rather than variable behavior of a single direction. The data comes from the last 24 hours, 
the two referenced links are operated by different providers on very different paths (opposite directions). Over 
shorter distances, we've definitely seen input errors that have affected PNI connections within a datacenter as well. 
In the case of the last PNI issue, the other party swapped their transceiver, we didn't even physically touch our side; 
I note this only to express that I don't think this is just a case of the transceivers that we are sourcing.

Comparatively, other than clear transport system issues, I don't recall this sort of thing at all with 10G "wavelength" 
transport that we had purchased for years prior. I put wavelengths in quotes there knowing that it may have been a 
while since our transport was a literal wavelength as compared to being muxed into a 100G+ wavelength.

On Mon, 19 Jul 2021 at 12:01, Saku Ytti <saku () ytti fi<mailto:saku () ytti fi>> wrote:
On Mon, 19 Jul 2021 at 19:47, Graham Johnston
<johnston.grahamj () gmail com<mailto:johnston.grahamj () gmail com>> wrote:

Hey Graham,

> How commonly do other operators experience input errors with 100G interfaces?
> How often do you find that you have to change a transceiver out? Either for errors or another reason.
> Do we collectively expect this to improve as 100G becomes more common and production volumes increase in the future?

New rule. Share your own data before asking others to share theirs.

IN DC, SP markets 100GE has dominated the market for several years
now, so it rings odd to many at 'more common'. 112G SERDES is shipping
on the electric side, and there is nowhere more mature to go from
100GE POV. The optical side, QSFP112, is really the only thing left to
cost optimise 100GE.
We've had our share of MSA ambiguity issues with 100GE, but today
100GE looks mature to our eyes in failure rates and compatibility. 1GE
is really hard to support and 10GE is becoming problematic, in terms
of hardware procurement.


--
  ++ytti