Proposal 2 (P2)

Katzenpost + [Mailproxy]

Mailproxy is a mailserver & mixnet client intended to run on the users’ devices. Not as a provider’s mail server, as this would create an “entry-node” to the mixnet which defeats certain security guarantees.

The client would need to configure the SMTP socket address (IP:port) of the mailproxy.

Outlook clients use [MAPI] . It’s possible to use MAPI over HTTP.

Differences between loopix and katzenpost

In loopix there’s only 3rd party anonymity (unlinkability), while katzenpost introduced the concept on “ephemeral” providers, which are the entry point for the client/user to query their “remote spool” to retrieve/send the messages via Single Use Reply Blocks ( [katzenpostSURB] s).

This way in katzenpost there’s also sender and receiver anonymity (unlinkability)

In loopix the user keys are also in the PKI, (are they also in katzenpost?)