RTT meaning

[Mark_Andrews at isc.org]

> I often heard of local name server using RTT to select the best
> Root name server for query.  How is RTT calculated ?  I think
> that it won't be just simply sending Ping packet and calculate
> the Round Trip Delay since Ping packet only counts for network
> delay but it does not count for the Root DNS server respond
> time to query.
> 
	From the response times of previous queries to the (root)
	servers.  Why waste network bandwidth sending pings when
	the queries will do the job for you.

	Mark
--
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
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