% > >even if you do this the end system identifier needs to be globally
% > >scoped, and you need to be able to use the end system identifier
% > >from anywhere in the net, as a means to reach that end system.
% >
% > DNS is a bright and successfull example of such deal.
%
% actually, DNS is slow, unreliable, and often out of sync with reality.
%
% DNS reverse lookup tables (PTR) are not as well maintained as forward
% lookup tables (A) so they're even less reliable.
This is an assertion that I've heard over the years
and I've come to beleive (based on regular audits of
the in-addr space) that this is an Internet equivalent
of an urban legend. I'd really like to see your backing
data on this.
The 2q2000 data for the in-addr tree shows 77402 unique
servers answering for 693,337 zones.
19515 servers blocked/refused data. Of the 57887 that
answered, these are the numbers for improper configuration:
BAD_SERVER: 4278
FORMERR: 8
NXDOMAIN: 28
So, of the 57,887 visable servers, 4314 are improperly configured
in the visable in-addr.arpa. tree. Thats 7.45% of the
servers being "not well maintained". I know of no similar data
collected on the forward tree as a whole. I'm currently checking
the data in a few TLDs to see if spot data may indicate a trend.
Now as to the accuracy of the data in the zones, that depends
on the owner of the data beleiving the data correct and that
will be very hard to check.
--bill
