Re: [dnsext] RFC 3484 section 6 rule 9 causing more operational problems

[Paul Vixie <[e-mail]>]

>    /24 - could be, but is it worth?
>    /16 - not a chance; there are a lot of LIRs with /20 in RIPE region, so
>    /16 is way too
>    much (and you can have quicker connection to U.S. than to some parts of
>    Europe).

there are three modes here.

first, you can do some good.
second, you can do some harm.
third, you can have no effect.

RFC 3484 as it is can sometimes do some good.  and if it ends up using
address similarity as an indicator of probable proximity and it's wrong,
then it'll be the same as random.  only in the case where the server is
depending on rr ordering within rrsets, which dns has never guaranteed
and which many caches (both rdns and stubs) randomize or reorder anyway,
and where the server's imputation of topology knows about every private
interconnect that may affect client performance, would RFC 3484 do harm.