-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 25/09/14 09:48, Trevor Perrin wrote: > Bouncing messages whenever Bob changes his key seems bad. Alice > might send a message and then disconnect, so you can't count on her > mail client to auto-resend, and the message might be lost or > delayed. > > So Alice should probably confirm the key with the recipient's > provider before sending a message. In which case Bob's email > header doesn't need to list Bob's key, it just says "X-Lookup-Key: > True", and Alice remembers that. > > Bob's server would get two connections per message (one from > Alice, one from Alice's MTA). It would be nice if Alice could > contact Bob's MTA once to confirm the key and send the message. I > suppose that's feasible in a centralized system where the server > handles spam by tracking reputations for Alice and Bob. But it > doesn't seem feasible for email.
Using a separate connection to look up the key provides a nice opportunity to route the lookup through an anonymity system. Bob can anonymously look up his own key from time to time, and if his provider supplies the wrong key he can switch to another provider and bitch to his friends, some of whom may believe him. No public consensus on the truth of Bob's claims is required. On receiving the message from Alice, Bob's provider will realise who made the anonymous lookup, but by then it will be too late to supply the wrong key. The anonymity system could be Tor, or a special-purpose system in which each encrypted mail provider operates a relay. Cheers, Michael -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQEcBAEBCAAGBQJUJXThAAoJEBEET9GfxSfMcoUH/0s8ir4kiXlmFQKrXVs1koTc QWvpcoSeiBbzORYSb1zHK44S7O+h0bBi94Kvc2+xsO5deNB/YHBqOlQZNIb8o1bY 1wt226PZ2wyrIZB701qxnQ4iAXhrEb8jQ9QMnUVakRjqC1GU4o1FLyAYxfzKLp1N UdibZRjtKsIPsh7bl4m8xiZmrc8Lf6IUeIuOwqYDPdx8jOBplYNGP8BU7Jd9F+gV nv5yo205/4aOeiEyM4EgeOjyH+yawkxmqM8BOAo0+nCfkk1LNyopZAyrZh8nCcYi C8lx1aJRSNDMcW3AgFXYEGtY4dc5UOs1MtK2DZUT3Ar7frcu+HiFuaOTE1fX1jE= =lXLy -----END PGP SIGNATURE----- _______________________________________________ Messaging mailing list [email protected] https://moderncrypto.org/mailman/listinfo/messaging
