link monitoring

Saku Ytti saku at
Sat May 1 07:13:24 UTC 2021

On Fri, 30 Apr 2021 at 00:35, Eric Kuhnke <eric.kuhnke at> wrote:

> The Junipers on both sides should have discrete SNMP OIDs that respond with a FEC stress value, or FEC error value. See blue highlighted part here about FEC. Depending on what version of JunOS you're running the MIB for it may or may not exist.

This feature will be introduced by ER-079886 in some future date. You
may be confused about OTN FEC, which is available via MIB, but
unrelated to the topic.

I did plan to open a feature request for other vendors too, but I've
been lazy. It is broadly missing, We are doing very little as a
community to address problems before they become symptomatic and
undercapitalising the information we already have from DDM and RS-FEC.

Only slightly on-topic; people who interact with optical vendors might
want to ask about propagating RS-FEC correctable errors. RS-FEC of
course is point-to-point, so in your active optical system it
terminates on the first hop. But technically nothing stopping far end
optical link inducing RS-FEC correctable error, if there was an error.
Perhaps even standard to discriminate between organic near-hop RS-FEC
correctable error from induced.
We have a sort of precedent for this, as some cut-through switches can
discriminate between near-hop FCS error from other type of FCS,
because of course sender will know about FCS after it already sent the
frame, but it can add some symbol in this case, to let the receiver
know it's not near-end. This allows the receiver to keep two FCS


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