[SIP Beyond VoIP] Sylkserver – I'm too stupid to understand the sparse documentation

[Paul]

Hello,

I'm trying to setup Sylkserver as a SIP/XMPP Gateway. My first problem is that I find it really hard to comprehend how Sylkserver really works in general. I also feel that some configuration options are not exactly self-explanatory and the brief comments in the config files don't help much. I read all the documentation on the website and searched the archives, but I'm still lost. Trial and error also didn't work.

What I wanted to achieve is that the users on my XMPP server can call an Asterisk server and receive calls from Asterisk.

XMPP client <---> example.net (XMPP server) <---> gate.example.net (Sylkserver) <---> pbx.example.net (Asterisk SIP)

If this wouldn't work with Syslkserver or if Sylkserver isn't recommended as a solution for such a gateway I can stop right here. If it's suitable for my case, here is what I don't understand fully:

I need to set a domain for the xmppgateway. This would be gate.example.net?
I also need a SRV record _xmpp-server._tcp.gate.example.net
Do I need additional server records for SIP like _sip._udp.example.net?

For what is
; default_application = conference
good for?

Where and when is the application_map applied? (incoming, outgoing requests?)
; application_map = echo:echo,123:conference,test:ircconference,gmail.com:xmppgateway
gmail.com???

$ nc sylkserver.example.net 5269
<stream:stream xmlns:stream='http://etherx.jabber.org/streams' xmlns='jabber:server' to='gate.example.net' version='1.0'>
<stream:stream xmlns:stream='http://etherx.jabber.org/streams' xmlns='jabber:server' xmlns:db='jabber:server:dialback' version='1.0' from='gate.example.net' id='d9fd3d4cd1fc383e'><stream:error><invalid-namespace xmlns='urn:ietf:params:xml:ns:xmpp-streams'/></stream:error></stream:stream>

why does Sylkserver return this error?

Why does Sylkserver not offer TLS?
From prosody.log:
Jun 17 13:12:55 s2sout559b75dd3910      info    Outgoing s2s stream example.net->gate.example.net closed: Encrypted server-to-server communication is required but was not offered

valid certs are configured and it works on SIP-TLS, tested with
$ openssl s_client -connect sylkserver.example.com:5061
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