Re: [karp] BFD Authentication costs

Joel Halpern Direct <jmh.direct@joelhalpern.com> Wed, 31 July 2013 12:40 UTC

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Date: Wed, 31 Jul 2013 08:39:38 -0400
From: Joel Halpern Direct <jmh.direct@joelhalpern.com>
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To: Russ White <russw@riw.us>
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Cc: karp@ietf.org
Subject: Re: [karp] BFD Authentication costs
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After I sent my note, I thought of some cases on my own.  But I do think 
it is important that we think about the scale at which we want to make 
this work.

Yours,
Joel

On 7/31/13 8:38 AM, Russ White wrote:
>
>>> In practice, on most devices, when BFD is run at low intervals it is
>>> done directly on the line card.  Doesn't this mean that in most
>>> topologies the number of sessions is roughly the same as the number of
>>> physical ports on the device?
>>
>> Not necessarily. Our customers use vlan tagged IP Interfaces where the #
> of
>> sessions on a physical port can be greater than 1 (and it usually is).
>
> I would say this is pretty normal --ie, customers running multiple logical
> interfaces is more common than the one-to-one situation, in my experience.
>
> Russ
>