[jdev] Re: VTD-XML version 1.6

Fri May 19 02:25:56 CDT 2006

I like xmpp a lot better than SIP ... it ought to replace SIP in the 
future....
----- Original Message ----- 
From: "Alexander Gnauck" <gnauck at ag-software.de>
To: <jdev at jabber.org>
Sent: Thursday, May 18, 2006 11:31 PM
Subject: [jdev] Re: VTD-XML version 1.6


> crackeur at comcast.net schrieb:
>>  you confused me even more...
>> I thought IM apps exchange xml messages (usually small),
>
> let me explain XMPP with this small example of a session:
>
> the client connects, open the socket and the XML Document
> C->S: <?xml version="1.0"?>
> C->S: <stream:stream xmlns:stream="http://etherx.jabber.org/streams" 
> xmlns="jabber:client" to="jabber.org" >
>
> server accepts the socket and opens the XML document
> S->C: <stream:stream xmlns='jabber:client' 
> xmlns:stream='http://etherx.jabber.org/streams' from='jabber.org' 
> id='596931'>
>
> the client starts to authenticate
> C->S: <iq type="get" to="jabber.org" id="auth_1" >
> <query xmlns="jabber:iq:auth">
> <username>alex</username>
> </query>
> </iq>
>
> S->C: <iq type="result" id="auth_1" >
> <query xmlns="jabber:iq:auth">
> <username>gnauck</username>
> <password/>
> <digest/>
> <resource/>
> </query>
>       </iq>
>
> C->S: <iq type="set" to="jabber.org" id="auth_2" >
> <query xmlns="jabber:iq:auth">
> <username>gnauck</username>
> <password>secret</password>
> <resource>Psi</resource>
> </query>
>       </iq>
>
>
> S->C: <iq type="result" id="auth_2" />
>
> C->S: <message type="chat" to="romeo at jabber.org" > <body>Test</body>
>      </message>
>
> Client closes the connection, which means it closes the XML Document
> C->S: </stream:stream>
>
> Server is closing the XML Doc too
> S->C: </stream:stream>
>
> you see we have 2 complete XML Documents. The client doc and the server 
> doc. Our messages, also called stanzas are the 1st level child elements of 
> the document. If you see the stanzas as a single xml doc and not in the 
> context of the whole document you loose the namespace of the stanzas, and 
> your software is not namespace correct. This is why parsing XMPP XML is a 
> bit tricky and the most out of the box parsers don't work very well 
> without modifying them. My exapmple shows the old jabber style 
> authentication. It gets even more complicated when using SASL, START-TLS 
> and other stuff which resets the stream and opens the document again.
>
> > why do they exchange huge XML docs? It sounds not just bad, but
> > unnecessary...
>
> i don' think so. Because of this XMPP is a very clean and solid protocol. 
> Clean, simple, powerful, extensible.....
>
> Alex
>
>