On Mon, Sep 14, 2020 at 5:40 PM Brandon Long <blong=
Yes, I should point out that at Google, we do multiplex multiple
connections between a proxy frontend and our actual smtp servers, but we
don't do it at the command level, but at the stream level, which is a much
simpler mechanism for integration and utility across different protocols
(we do this with imap, pop, xmpp, and probably others, on top of the
various types of HTTP).
Envoy has at least some support for this:
STARTTLS requires some OOB handshaking to make this work which I'm not
sure that Envoy supports, but I'm sure it could be extended to do it.
Ditto with passing the connection metadata forward, though envoy probably
already does that as HTTP headers on the request stream.
We're making some progress on STARTTLS support in Envoy
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