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Re: [RRG] Why delaying initial packets matters
Eliot,
On Feb 11, 2008, at 1:55 AM, Eliot Lear wrote:
An obvious first candidate would be DNS I think.
The DNS provides a useful model for a pull-based system, but I'm not
sure it would be particularly useful to assume if something can be
shown it can't work if you put the mapping into the DNS, that implies
it can't work period.
Keeping in mind that these queries are likely recursive, we shift
our scrutiny to the name server. Supposing a query is dropped, will
the next query go to the same name server or to another listed name
server? If it's to another name server could that query also be
dropped? Will behavior differ based on the number of zone cuts and
whether the appropriate name servers are in the same proximity as
the parent servers?
It's amazing that the DNS works at all, isn't it? And yet, with all
that recursion and potential for timeout, it seems to work reasonably
well.
However, as I've said on several occasions, while I might personally
use the DNS as a model for a pull-based system (primarily because most
folks think they understand what that implies), I don't think the DNS
(as it exists today) is the right answer. For one thing, the timeouts
would likely need to be rejiggered since the existing timeouts are
based on assumptions that were derived from when 56 Kbps was
considered "high speed".
As far as I can tell, a pure pull-based system is likely as unworkable
as a pure push-based system. As Robin has suggested, a hybrid system
is probably going to be necessary, so there are yet more tradeoffs to
consider.
Regards,
-drc
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