Subject: Re: Trees have one root

From: John Stracke <[email-masked]>
Date: Tue, 30 Jul 2002 14:10:38 -0400

Eric A. Hall wrote:

>>>In general you are right, but in practical terms, there isn't much
>>>difference between 20, 200 or 2000 TLDs, as long as they don't also
>>>introduce, say, a billion phones to the service network.
>>>
>>>
>>no.  a few hundred million hosts using (on average) two dozen popular TLDs
>>will generate twice the load on the roots as the same number of hosts
using
>>(on average) a dozen popular TLDs.
>>
>>
>
>That only holds true if the number of queries also doubles.
>
False.  The caching system means that the roots don't pay per query;
they pay per cache miss--and the number of cache misses is going to be
roughly proportional to the number of TLDs.

-- 
/===========================================================\
|John Stracke      [email-masked]                  |
|Principal Engineer|http://www.centivinc.com                |
|Centiv            |My opinions are my own.                 |
|===========================================================|
|We must be devious, cunning, inventive... too bad we're us.|
\===========================================================/

---

From: "Christian Huitema" <[email-masked]>
Date: Wed, 31 Jul 2002 17:24:25 -0700

> Mr. Hall's original and current thesis is that adding TLDs as 
> an act is harmless, and that the real point of concern is the number
of queries.
> This point has not yet been disproven. The counter-argument 
> that a busy ("popular") TLD will result in more queries only proves
the point,
> although the advocates of such an argument refuse to admit that the
> frequency of queries -- the number of queries over time, the 
> measure of "popularity" -- is the issue, not the number of TLDs.

Except that the cache misses hitting the root are by no means *linearly*
proportional to the number of queries. As the popularity of the servers
in a domain increase, the load on the root grows asymptotically towards
1 request per TTL per resolver, and in fact it approaches the limit
quite fast. Split .COM in two, both halves will be very the asymptote,
both would generate almost the same load on the root as the previous
combination. Adding more TLD and splitting the existing load across
these new TLD would definitely have an impact on the root.

-- Christian Huitema