On Tue, 17 Apr 2007 01:59:23 +0100, Jim Fenton <fenton(_at_)cisco(_dot_)com>
wrote:
Option 3: As presented at IETF 68, upward queries would be performed if
a NODATA response is required until the verifier gets to a TLD (or
something that acts like one).
Discussion: Option 3 is simplest for the publisher, but likely to be
considered unacceptable due to the potentially unbounded querying of
higher-level domains, and possible load on root and/or TLD servers.
So any upward search needs to stop as soon as you find a level with an
SOA. If you haven't found whatever SSP you were looking for by then, then
you can assume it doesn't exist.
But, as John points out, SOA records tend not to get cached, so you might
need to insist on an authoritative response and that places a strain on
the official name servers for the zone, not to mention the extra lookup
for the SOA.
--
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131
Web: http://www.cs.man.ac.uk/~chl
Email: chl(_at_)clerew(_dot_)man(_dot_)ac(_dot_)uk Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9 Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5
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