OT: SASL questions

[Richard Hector]

Hi all,

Apologies for the somewhat off-topic questions - I'm trying to get my
head around SASL, and what it is/does.

I can see that a (SMTP, IMAP etc) server can offer various
authentication methods, which are pre-defined and which the client can
choose from. SASL then seems to define how those work.

But dovecot and cyrus-sasl both seem to offer a client-server interface,
usable by eg postfix, which I don't see any reference to in SASL
summaries online.

Is that a standard interface? ie can a client like postfix talk to
either dovecot or cyrus without knowing the difference? Are there others?

Is there a good reference to this somewhere, short of reading the RFCs?

And is there any option (current or proposed) to let dovecot act as a
client, rather than a server?

Thanks,
Richard