Re: ALPN

It appears that Claus Assmann  <[email protected]> said:
>On Thu, Jul 29, 2021, Arnt Gulbrandsen wrote:
>
>> In this case, we're talking about whether there is one different ALPN or
>> four. Either case suffices to protect email servers from being involved in
>
>Since there are already IDs for IMAP and POP3, it seems we are down to
>3 (+SMTP) or 4 (+SUBMIT) unless we want to break existing applications?

Given that clients often don't know whether they're talking to an SMTP or a submission
server, and servers don't know which one they are or maybe both, one ALPN would be plenty.

It's still pretty common for a server to offer SMTP on port 25, which turns into submission
if the client authenticates.

R's,
John