Re: [perpass] Another mail-related proposal

Randy Bush <randy@psg.com> Tue, 20 August 2013 05:27 UTC

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Date: Tue, 20 Aug 2013 14:27:36 +0900
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From: Randy Bush <randy@psg.com>
To: Jim Fenton <fenton@bluepopcorn.net>
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Cc: perpass@ietf.org
Subject: Re: [perpass] Another mail-related proposal
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>> smtp is hop by hop.  just because A encrypts to B, A has zero assurance
>> that B encrypts to C.  hence, e2e encryption is pretty much mandatory
>> against a purely passive attacker.
> ...which goes back to the original thing I was suggesting: that A should
> be able to signal to B that it should only relay the message (e.g., to
> C) if the channel is also encrypted and that C also will observe the
> restriction if it needs to relay the message further.

and A trusts B and B's software and configuration why?  transport
encryption by default good.  e2e encryption by default gooder.  both
great.

randy