[dns-operations] DNSSEC parameter BCP

[Viktor Dukhovni]

On Sun, Jun 18, 2023 at 06:12:27AM +0000, Geoff Huston wrote:

> >> The BCP algorithm is ECDSAP256SHA256(13).  This is both more secure and
> >> more compact than RSA.  It is in wide use:
> >> 
> >>    https://stats.dnssec-tools.org/
> >>    https://stats.dnssec-tools.org/#/?dnssec_param_tab=0
> >> 
> >> Today, out of 22,010,850 known signed zones, the number with algorithm
> >> 14 KSKs is 9,982,219 or just over 45%.

[ Apologies on the typo, that should also have been 13 not 14. ]
Some days later, the total signed with algorithm 13 has crossed 10
million.

> The last time I looked at the capabilities of validators in recursive resolvers
> comparing levels of support for RSA and ECDSA P256 SHA256 was in November 2021
> (https://www.potaroo.net/ispcol/2021-11/ecdsa.html)

A more recent internal study shows negligible differences in validation
rates between RSA(8) and ECDSA (13), the expected/unexpected
success/failure rates are effectively the same.

Any validating resolver that supports only RSA would be unable to
validate 90 TLDs and ~45% of signed zones (10.04 million out of 22.45
million).

At this point there should be no concerns about support for ECDSA P-256.
If anything, given e.g. recent "crypto policies" in RedHat systems,
there are now potential problems with RSA validation for the remaining
pockets of zones signed with algorithms 5 and 7 (~20k and ~127k zones
respectively).

-- 
    Viktor.