RE: Signed/Encrypted Mail URL

There's no reason why 'mailto:[email protected]' shouldn't
send a signed and encrypted message, if there's mutual
agreement about the preference to receive and the capability
to send.

Negotiation about capabilities and preferences seems to
be better handled in a protocol-dependent way, for HTTP
using UPGRADE and for mail using RESCAP.

For the former, see draft-ietf-tls-http-upgrade-02.txt;
for the latter, see draft-hoffman-rescap-mua-01.txt
http://www.ietf.org/ietf/99mar/rescap-agenda-99mar.txt,
draft-beck-rescap-req-02.txt, draft-hoffman-rescap-protocol-01.txt.

There's been a lot of pushback about creating new URL
schemes that differ from the 'original' URL scheme only
in the security parameters (https vs http), and an intent
to not continue in that direction.

Larry
-- 
http://www.parc.xerox.com/masinter