[Juser] 'lightweighting' Jabber chat for sllloooooow links...& UDP?!

Lines, David David.Lines at uk.thalesgroup.com
Thu May 18 09:20:42 CDT 2006


hi. i am looking to set up Jabber chat over a HF radio link at a speed of
4.8kbps and with high latency (ping ~ 7secs)!! i would love any assistance
in where i can start to tweak for this situation. while the data rate will
not be high for text chat, the high latency means i need to reduce any
handshaking as much as possible. with a sniffer i notice there is a large
amount of handshaking taking place even after the connection is established.
i havent yet looked into detail what these packets are doing but i guess i'm
in for a crash course in xmpp/xml/impp?! 

My initial high level thoughts are to 'turn off' negotiation for voice and
video. I notice 'Keep_Alives' is a client option that could be turned off. i
know there are proprietry lightweight LAN chat apps but I want to keep to
open source standards, ie Jabber. Is there provision for 'pipe-lining'
multiple xmpp commands (ie similar to what is proposed for SMTP with
Pipelining (RFC-2197) - basically sending several commands at once and
waiting for the respective ACKs to return in 1 packet).

Also can Jabber be set for a UDP connection instead of TCP? The standard
(RFC-3920) implies TCP but doesn't explicitly rule out UDP, but this forum
reply does!

http://mail.jabber.org/pipermail/juser/2002-September/000070.html
<http://mail.jabber.org/pipermail/juser/2002-September/000070.html> 

I see Jingle is looking at RTP over UDP. I'm new to all of this but I see
there are <transport> commands. I'm currently evaluating Wildfire-2.6.2 and
they aren't any configuration options for UDP. IANA reserves xmpp port 5222
for TCP and UDP. Could this be possible with access to the client and/or
server source codes?

And one more qu... can Jabber talk client to client, or client to client
after the server goes down. Initial testing shows that once the server is
gone so does any client to client chat (basically it is relayed through the
server)

any help greatly appreciated! cheers david
david.lines at uk.thalesgroup.com



More information about the JUser mailing list