Creating A Conference; Joining A Conference; Terminating A Conference - AudioCodes Mediant 1000 User Manual

SIP User's Manual
1.1.2

Creating a Conference

The Mediant 1000 conference server creates a conference call when the first user joins the
conference. To create a conference, the Application Server should send a regular SIP
INVITE message to the Mediant 1000. The User Part of that Request-URI should include
both the Conference Service Identifier (indicating that the requested Media Service is a
Conference) and a Unique Conference Identifier (identifying a specific instance of a
conference).
INVITE sip: conf100@audiocodes.com SIP/2.0
By default, a request to create a conference reserves three resources on the Mediant
1000. It is possible to reserve a larger number of resources in advance by adding the
number of required participants to the User Part of the Request-URI. For example,
'6conf100' reserves six resources for the duration of the conference.
If the Mediant 1000 can allocate the requested number of resources, it responds with a 200
OK.
The Conference Service Identifier can be set via the Mediant 1000 ini file (ConferenceID)
or via the Web interface. By default, it is set to 'conf'.
1.1.3

Joining a Conference

To join an existing conference, the Application Server sends a SIP INVITE message with
the same Request-URI as the one that created the conference. Each conference
participant can use a different coder, negotiated with the Mediant 1000 server using usual
SIP negotiation.
If more than the initially requested number of participants try to join the conference (i.e.,
four resources were reserved and a fifth INVITE is received) and the Mediant 1000 has an
available resource, that request shall be granted.
If an INVITE to join an existing conference is received with a request to reserve a larger
number of participants than initially requested, it shall be granted if the Mediant 1000 has
enough available resources. A request for a smaller number of participants shall not be
granted as this might create a situation that existing legs need to be disconnected.
The maximal number of participants in a single conference is 60. The maximal number of
participants that actually participate in the mix at a given time is 3 (the loudest legs).
The Application Server can place a participant on Hold/Un-hold by sending the appropriate
SIP Re-INVITE on that participant dialog.
1.1.4

Terminating a Conference

The Mediant 1000 never disconnects an existing conference leg. If a BYE is received on an
existing leg, it is disconnected, but the resource is still saved if the same leg (or a different
one) wants to re-join the conference. This logic occurs only for the initial number of
reserved legs.
For example:
1. INVITE reserves three legs.
2. A, B, and C joins.
3. A disconnects.
4. A joins (guaranteed).
5. D joins.
6. A disconnects.
7. A joins (not guaranteed).
Sending a BYE request to the Mediant 1000 server terminates the participant's SIP session
and removes it from the conference. The final BYE from the last participant ends the
conference and releases all conference resources.
Version 5.0 265
8. Media Server Capabilities
December 2006