Re: On email and web security

[Phillip Hallam-Baker <[e-mail]>]

On Sat, Jan 2, 2016 at 10:38 AM, John Levine <[e-mail]> wrote:
>>To send to a mailing list, the sender must either have a copy of the list or the system managing the list must decrypt and re-encrypt the
>>message.  Neither of these is a good fit with the current email architecture.  The former is secure but unwieldy; the latter is reasonably
>>efficient but breaks the desired end-to-end security.
>
> FYI, the Sympa list manager which is widely used in Europe does the
> latter, S/MIME key for the list, and the list software re-encrypts the
> messages to the recipients' keys.
>
> Given a choice between trusting the list software and trusting all of
> the subscribers, that seems a reasonable way to do it.

Using recryption means that you can meet both properties at once.

It is a very powerful tool and I remember Matt Blaze coming to tell us
about it. We have ignored it for 20 years.