A conversation can be created initially as a conference, or an existing two-party conversation can be escalated to a conference. In both scenarios, the application must join the conference before inviting new participants. An application can access the conference session from the conversation by means of the conversation’s ConferenceSessionproperty.

The following code demonstrates creating a conference session and then joining the conference.

Copy Code 
ConferenceSession conferenceSession =
conversation.ConferenceSession;
conferenceSession.BeginJoin(Conference_JoinCompleted,
conferenceSession);

The join operation without parameters will automatically create an ad hocconference and joins that conference. The BeginJoinmethod also has an overload that can be used to join a scheduled conference.

If a participant joins a conference, and the IsTrustedJoinproperty on the ConferenceJoinInformationobject is set to true, the participant is considered to be the conference Leader.

An application cannot use the impersonation API without possessing trust from the server, as provisioned as a GRUU in Active Directory. Once impersonated, an application may join any conference as if it were that user.