> >But even you would have to admit that by adding lots of TLDs, extra
> >orders of magnitude are induced in the DNS process, because queries
> >are going further up the tree than they would otherwise be.
>
> In theory, I would agree with Greg.
>
> In this case, however, .COM requests *always*
> go to the top of the tree (i.e. the root servers)
> because the .COM zone is being resolved by the
> root servers.
No, it's not that simple.
Some of the root servers ([a-i].root-servers.net) are also servers for
.com. Some are not: [j-m].root-servers.net. Some .com name servers are
not root servers: [j-k].gtld-servers.net.
DNS is based on caching and load balancing, and name servers estimate
round trip times and try to use the "nearest" server - ie. the one
that answers fastest.
Somewhat simplified, this means that for those name servers where
[j-k].gtld-servers.net answer fastest, a .com request does *not* have
to go to the root name servers.
It's probably more correct to say that in a *majority* of the cases,
.com requests go to the root servers because those root servers also
happen to be servers for .com.
Steinar Haug, Nethelp consulting, [EMAIL PROTECTED]
