Re: [idn] Using the last DNS header bit

[Bill Manning <bmanning@ISI.EDU>]

% >There will be deployment
% >problems using this bit due to some old DNS software using this bit
% >for non standardized behavior. This bit is being reserved for future
% >use, in case we encounter a problem that is of extremely high importance 
% >and where there is no way around it.
% 
% draft-ietf-dnsext-iana-dns-01.txt says that it is believed that current DNS
% implementations ignore this bit.


	Current does not mean deployed. Significant percentage of the deployed
	base is over five years old. Olafurs concerns are valid.


% >Most of the proposals that I have read can just as well use one of
% >the EDNS extension functions, for instance the extended flags (there are 12 
% >1-bit flags available).
% 
% Using EDNS gives an unacceptable overhead as older servers will
% give an error response when using it. That is why the flag is needed
% in the normal header. One can question why DNSSEC were allowed to
% use up two of the three unused bits, DNSSEC could have used EDNS?

	DNSSEC came along before EDNS.  Hindsight is nearly always 20/20


--bill