[c-nsp] BFD interval on a CRS3

[Pshem Kowalczyk]

Hi,


On 4 April 2013 14:44, Adam Vitkovsky <adam.vitkovsky at swan.sk> wrote:
> Hi Pshem,
> What did you use as the FRR mechanism, if any, along with the BFD testing please?

Yes, we did use RSVP-TE FRR for the protection.

>> it's threshold based, so once errors reach particular level switchover is triggered - whilst BFD has to actually lose those packets first.
> Well, unless you have the expensive modules that can do the FEC you will lose some data either way.

That's correct - data loss always occurs anyway (we've noticed that L2
seems to be more prone then L3). It's about the re-convergence time -
i.e. the time the packets do not arrive at the destination (either
because they've been lost or because they're getting re-routed and
delayed). Using WanPhy doesn't require the FEC ability (only OTU
framing needs it). As one of the tests we actually took pliers to the
wire to see what would happen. In our case - the traffic switched
before the scissors went all the way through (logs indicated that the
BER went above the thresholds before actual LOS).

kind regards
Pshem