That's very helpful, thanks. But it raises another question and that is how
does a host with the standard resolver query the internal firewall ( dns
server). Does it use UDP as well ? and I take it that total ICMP blocks on
the internal LAN obviously will cause distress for DNS? ( I think the only
way to communicate to the firewall is telnet ATT.

Thanks
Dave

Oh and to the rest of the group thankyou for the sparkling debate on mail
group etiquette. It kept me amused for hours 8-)
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