Classless IN-ADDR.ARPA delegation

[Michael Voight]

Barry Margolin wrote:
> 
> In article <99080808491004.11196 at dns.eklanda.net>,
> Magnus Benngard  <magnus at eklanda.net> wrote:
> >From name to IP no problem.
> >From IP to name - not working.
> >Should it work even if my ISP has not fix the Classless IN-ADDR.ARPA delegation?
> >(I am 100 percent sure my ISP has not delegated anything.)
> 
> No, it won't work if they haven't delegated.  It's not like normal reverse
> DNS, where you'll get reverse resolution if you use your own server, but
> not get it if you use an outside server.  The technique in RFC 2317 only
> works if the domain for the /24 block contains CNAME records that point
> into your subdomain.
> 

Then, optionally, can't he just pretend he owns the whole subnet and
serve that??? Of course, ptr records he doesn't have for the subnet will
not be resolved.

Michael