Request comment: list of IPs to block outbound

Saku Ytti saku at ytti.fi
Tue Oct 22 10:54:05 UTC 2019


On Mon, 21 Oct 2019 at 23:14, <adamv0025 at netconsultings.com> wrote:

> The obvious drawback especially for TCAM based systems is the scale, so not only we'd need to worry if our FIB can hold 800k prefixes, but also if the filter memory can hold the same amount -in addition to whatever additional filtering we're doing at the edge (comb filters for DoS protection etc...)

This is actually somewhat cheap problem, if you optimise for it. That
is rules are somewhat expensive, but N prefixes per rule are not, when
designed with that requirement. Certainly the BOM effect can be
entirely ignored. However this is of course only true if that was
design goal, won't help in a situation where HW is in place and
doesn't not scale there. Just pointing out that there are no technical
or commercial problems getting there, should we so want.

-- 
  ++ytti



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