reverse DNS considered pointless was: [6bone] Fwd: BCP 80, RFC 3681 on Delegation of E.F.F.3.IP6.ARPA

[Matthew Luckie]

> I know for sure that the IPv6 reverse tree is much better populated
> and usefully (no automatically generated reverses) populated than
> the counterpart IPv4 tree. Main reason: dnsspamming irc kiddo's.
> Next to that the people that do IPv6 want it to succeed and thus also
> put those things neatly into the reverse and forward DNS.
> Btw, I know from experience a nice reverse DNS tree setup which has
> more entries (non-spammed btw) than most hosting ISP's serve DNS for
> websites :) Eat 18mb of ascii dns zones <grin>

just a small amount of stats from someone who is not big on stats:

i did a DNS walk of ip6.int about 9 months ago.

of the ~31k addresses i got, 21k were automatically generated (2x 10k, 
1x 1k).  i saw a fair amount of DNS spamming, but it did not feel like 
IRC lamers had taken over the DNS.  From memory there was some kind of 
free DNS service behind a fair amount of the spam.

of the ~10k left, 2445 survived a sanity check (taking the name returned 
in the PTR and resolving for the IPv6 address returned as part of the walk).

of those 2445, i got a response rate of about 70% +/- 3% with 
traceroute, depending on where the tests were run from.  the majority of 
failures of communicating with an address were loops, followed by dead 
paths (hosts/networks that said nothing).  only a very small proportion 
of addresses that were not actually reachable had a router send an ICMP 
response saying so.

http://voodoo.cs.waikato.ac.nz/~mjl12/ipv6-scamper/