2.5.18 Subscribe to Conference Events


This use case, illustrated in the following diagram, describes how a protocol client can subscribe to Communications Server conference events.

Steps for Subscribe subscribing to conference events

Figure 17: Steps for subscribing to conference events



  • The protocol client is present in a Communications Server conference, similar to what is described in section 2.5.17.


  1. The protocol client sends a SIP subscribe message to Communications Server to subscribe to conference events, as described in [MS-SIPRE] and [MS-CONFBAS].

  2. Communications Server sends a SIP 200 OK with Roster and notifications to the protocol client, as described in [MS-SIPRE] and [MS-CONFBAS].

  3. Subsequent Roster Updates are sent by Communications Server to the protocol client with SIP BENOTIFY, as described in [MS-SIPRE] and [MS-CONFBAS].


  • The protocol client gets notifications from Communications Server every time the conference state changes.