nanog mailing list archives

Re: BCP 38 coverage if top x providers ...


From: Jared Mauch <jared () puck nether net>
Date: Tue, 22 Nov 2016 10:44:09 -0500


On Nov 19, 2016, at 9:13 PM, Frank Bulk <frnkblk () iname com> wrote:

My google fu is failing me, but I believe there was a NANOG posting a year
or two ago that mentioned that if the top x providers would implement BCP 38
then y% of the traffic (or Internet) would be de-spoofed.  The point was
that we don't even need everyone to implement BCP 38, but if the largest
(transit?) providers did it, then UDP reflection attacks could be minimized.

If someone can recall the key words in that posting and dig it up, that
would be much appreciated.

If you assume 80% of traffic comes out of your local CDN node, that remaining 20%
may not be too difficult for you to do something with.  The problem appears because
various engineering thresholds that existed in the 90s have been violated.

40(64) byte packet testing is no longer the norm by vendors.  Those of us who carry
a full table and are expected to provide all the features are the minority in
purchasing equipment by volume and revenue so the push is harder.  A double lookup
of the packet is twice as expensive and perhaps impractical in some (or many) cases.

- Jared

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