How Jitsi work


#1

Hi together,

i try to understand deeper how jitsi works.
I understand that the Video-Bridges (VB) publish his status to the Node and Jicofo get this information as a notification and can work with it.

But how Jicofo initialized new conference on the vb?

When i look at the jicofo.log. I finde some interesting informations.

org.jitsi.jicofo.xmpp.FocusComponent.handleConferenceIq().402 Focus request for room: shop@conference.mydomain.ru

org.jitsi.jicofo.FocusManager.log() Created new focus for shop@conference.meeting.oesolution.ru@auth.mydomain.ru conferences count: 1 options:

in the prosody config i found

Component "focus.mydomain.ru"
    component_secret = "XXXX"

and in the jicofo config i found

# sets the username to use for XMPP user logins

JICOFO_AUTH_USER=focus

# sets the password to use for XMPP user logins

JICOFO_AUTH_PASSWORD=XXXXX

So i can reconstruct that jicofo communicate to the component as a focus user to send over xmpp a command to the VB.

But how? Because the VB is only a publisher in xmpp. How the VB get information to create a new conference or something else.


#2

So here are the overall steps in the communication between client, jicofo and jvb.

  1. A client connects to the xmpp, and sends an IQ to the jicofo component address.
  2. Jicofo creates a room, joins the room, and make the one who requested to create the room an owner in the room, if he is the first one.
  3. The client receives the succesfull response from jicofo and joins the room.
    Nothing happens, here as there is just one participant.
  4. A second participant joins, jicofo sees that and starts the process of connecting both clients
  • sends an IQ to the jvb component address to allocate channels for both participants.
  • uses the allocated channels data to create jingle session-initiate, which then sends to both clients
  1. Clients accept it and start sending and they are now connected using jvb.

The pubsub you are mentioning is just for jicofo to see available bridges, and how busy are they, so it can balance between them. Jicofo uses the videobridge component address to communicate with it.

Hope this helps.


#3

HI Damian,

that helps! Thank you

All the first communication takes places via XMPP between Jicofo and the VB. The SIP communication will be initialized via XMPP too? With the xmpp jingle extension. Right?

But important to know is. Has the VB an own sip-communicator? Else the communication should be always run over Jicofo (p2p deactivated):

So I cant imagine that. I think after the initialization the communication should shows like this:


#4

Can you explain what do you mean by ‘sip communication’ and when you say the communication between x and y, what do you mean, signalling or media?

Signalling is always to the xmpp server while media (p2p disabled) is always between client and bridge.