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Re: (DNS) consensus wording

From: Anawat Chankhunthod <chankhun@catarina.usc.edu>
Date: Sat, 30 Mar 1996 17:53:49 -0800
Message-Id: <199603310155.RAA21642@catarina.usc.edu>
To: Koen Holtman <koen@win.tue.nl>
Cc: jg@w3.org, http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com

> Change to:
> 
>  If clients cache the results of name lookups for performance reasons,
>  they are strongly encouraged to get and observe the TTL (Time To
>  Live) information reported by the name server.  If this is not
>  feasible, clients must not cache the results of name lookups for
>  longer than 10 minutes, and must immediately discard a name lookup
>  result if a network error occurs when using the result to initiate a
>  connection.


I have some additional ideas. Danzig., et.al (SIGCOMM92 ??) shows that 
NEGATIVE caching DNS will help to reduce DNS traffic quite a bit. 
Negative cache means when DNS lookup fail (may be after 2-3 trails) for
that particular host, we should cache the result (the failure) for a short
time to avoid subsequent look up (which likely to fail again). Say 2 minutes.

Anawat
Received on Saturday, 30 March 1996 17:59:10 EST

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