Topic Last Modified: 2010-12-12

If your organization has users who need to attend Microsoft Lync Server 2010 communications software on-premises conferences when they are out of the office or do not have access to a computer, you can deploy dial-in conferencing so that they can join the conference by using a public switched telephone network (PSTN) phone.

Dial-in conferencing is an optional feature when you deploy Lync Server 2010 Conferencing. Although dial-in conferencing uses some of the same Lync Server components that Enterprise Voice uses, you can deploy dial-in conferencing even if you do not deploy Enterprise Voice.

Note:
If you deploy dial-in conferencing, you must deploy it in every pool where you deploy Lync Server 2010 Conferencing. You do not need to assign access numbers in every pool, but you must deploy the dial-in feature in every pool. This requirement supports the recorded name feature when a user calls an access number from one pool to join a Lync Server 2010 conference in a different pool.

Conferences must be enabled for dial-in access in meeting policy. By default, conferences that are enabled for dial-in access include the following information in the conference invitation:

Dial-in conferencing supports both enterprise and anonymous users. Enterprise users have Active Directory Domain Services (AD DS) credentials and Lync Server accounts within their organization. Anonymous users do not have enterprise credentials within your organization. In the dial-in conferencing context, a user in a federated partner’s organization who uses the PSTN to connect to a conference is treated like an anonymous user. For dial-in conferencing, unlike other contexts, federated users are not authenticated.

Enterprise users or conference leaders who join a conference that is enabled for dial-in access dial one of the conference access numbers and then are prompted to enter the conference ID. If a leader has not yet joined the meeting, users can either enter their unified communications (UC) extension (or full phone number) and PIN or wait to be admitted by a leader. Meeting organizers can join the meeting as a leader by entering just their PIN. The Front End Server uses the combination of full phone number or extension, and PIN, to uniquely map enterprise users to their Active Directory credentials. As a result, enterprise users are authenticated and identified by name in the conference. Enterprise users can also assume a conference role predefined by the organizer.

Note:
Enterprise users who dial in from an office IP phone or from Lync 2010 or Lync 2010 Attendant are not prompted for their phone number because they are already authenticated.

Anonymous users who want to join a dial-in conference dial one of the conference access numbers and then they are prompted to enter the conference ID. Unauthenticated anonymous users are also prompted to record their name. The recorded name identifies unauthenticated users in the conference. Anonymous users are not admitted to the conference until at least one leader or authenticated user has joined, and they cannot be assigned a predefined role.

Note:
Enterprise users who choose not to enter their phone number and PIN are not authenticated and, thus, are prompted to record their name and are treated as anonymous users in the conference.

At schedule time, the meeting organizer can choose to restrict access to the meeting by making the meeting closed or locked. In this case, dial-in users are requested to authenticate. If they fail or choose not to authenticate, they are transferred to the lobby, where they wait until a leader accepts or rejects them or they time out and are disconnected. Dial-in users hear music if they are waiting to be admitted to the conference. After they are admitted to a conference, dial-in users can participate in the audio portion of the conference and can exercise dual-tone multi-frequency (DTMF) commands by using the phone keypad. Dial-in leaders can exercise DTMF commands to turn participants' ability to unmute on or off, lock or unlock the conference, admit people from the lobby, and turn entry and exit announcements on or off. Leaders can also use a DTMF command to admit everyone from the lobby, which changes the permissions of the meeting to allow anyone who subsequently joins. All dial-in participants can exercise DTMF commands to hear Help, listen to the conference roster, and mute themselves.

Dial-in participants (that is, whether or not they dial from the PSTN), hear personal announcements during the conference, such as whether they have been muted or unmuted, the meeting is being recorded, or someone is waiting in the lobby.

Note:
Participants who join the conference by clicking a link instead of dialing in do not hear personal announcements.