There's only literally 3 options. PLAIN/SSL/STARTTLS. I see one of XMPP's major problems that even people who liked, advocated, and worked (not extensively, but

There's only literally 3 options. PLAIN/SSL/STARTTLS. I see one of XMPP's major problems that even people who liked, advocated, and worked (not extensively, but more than most I guess) with XMPP can't remember the name or details of a single XEP. In theory everything is compatible, in reality you're lucky if s2s works with the right crypto and you don't get gibberish because of OTR.