Defining Your Requirements for Conferencing


Topic Last Modified: 2012-10-16

Determining which conferencing capabilities to deploy depends not only on the features you want available to your users, but also on your network bandwidth capabilities.

The following list of questions guides you through the conferencing planning process to determine what features of conferencing you should deploy, based on your organization’s requirements.

  • Do you want to enable web conferencing, which includes document collaboration and application sharing?

    If so, you must enable conferencing for your Front End pool in the Microsoft Lync Server 2010, Planning Tool or in Topology Builder. Enabling conferencing enables both web conferencing and A/V conferencing.

    Application sharing requires and uses more network bandwidth than document collaboration. Microsoft Lync Server 2010 communications software provides a throttling mechanism to control each application sharing session. By default, this is set to 1.5 KB/second for each session.

    If you do not want to enable application sharing but you do want document collaboration, you can enable conferencing and use meeting policies to disable application sharing.

  • Do you want to enable A/V conferencing?

    If so, you must enable conferencing for your Front End pool in the Lync Server 2010, Planning Tool or in Topology Builder. Enabling conferencing enables both web conferencing and A/V conferencing.

    A/V conferencing requires and uses more network bandwidth than web conferencing (which includes document collaboration and application sharing). If you do not want to enable A/V conferencing but you do want web conferencing, you can enable conferencing and use meeting policies to disable A/V conferences.

    If you do want to enable audio conferences but not video conferences, you can enable A/V conferencing and use meeting policies to prevent video conferences. Alternatively, you can enable A/V conferencing and enable only certain users to start or participate in A/V conferences.


    Enterprise Voice is not necessary for A/V conferencing-if you enable A/V conferencing, your users can add audio to their conferences if they have audio devices, even if you use a PBX for your telephone solution.

  • Do you want to enable users to join the audio portion of conferences when using a PSTN phone?

    If so, deploy and enable dial-in conferencing. Invited users, both inside and outside your organization, can then join the audio portion of conferences by using a PSTN phone.

  • Do you want to enable external users with Lync Server clients to join the types of conferences that you have enabled?

    If so, you should deploy Edge Servers. Allowing external participation in meetings maximizes your investment in Lync Server. For example, users with laptops with Microsoft Lync 2010 can join conferences from wherever they are—at home, in the airport, or at customer sites.

    Additionally, with Edge Servers deployed you can create federated relationships with other organizations-such as your customers or vendors-and users from those organizations can more easily collaborate with your users.

  • Do you want to control the clients that are available for joining Lync Server meetings?

    If so, you should configure the meeting join page so that only the client options you want to support are available. Each time a user clicks a link to join a scheduled meeting, Lync Server detects whether a client is already installed on the computer. It then starts the default client and opens the meeting join page, which contains links for alternate clients. The meeting join page always contains the option to use Microsoft Lync Web App. In addition to this option, you can decide whether to include links for Microsoft Lync 2010 Attendee and previous versions of Communicator. For details, see Configure the Meeting Join Page.

A/V Conferencing Network Bandwidth Requirements

To plan for A/V conferencing, you need to understand the network bandwidth required by the type of conferencing media that your organization requires.

Before you enable users for A/V conferencing, you should ensure your network can handle the resulting load. Without sufficient network bandwidth, the end-user experience may be severely degraded. Anew feature in Lync Server 2010, call admission control, can help you manage the network bandwidth used by A/V Conferencing. For details, see Overview of Call Admission Control.

For information on media bandwidth requirements, see Media Traffic Network Usage.

Client A/V Devices

If you deploy audio conferencing on your network, your users will need audio devices such as headsets to participate. If you also deploy video conferencing, you will need to roll out video devices, such as webcams for users and the RoundTable device for conference rooms.

We recommend that you use unified communications (UC) devices that are certified by Microsoft for all device types, to ensure an optimal end-user experience. For details about UC-certified devices, see "Phones and Devices for Microsoft Office Communicator" at

For either audio or video devices, device rollout and user training are important issues for you to consider and plan for, to maximize your return on investment in conferencing.

Enabling External Participation in Conferences

You can greatly increase the benefits of your investment in Lync Server conferencing by enabling external users to also participate in conferences when invited. External users can include:

  • Remote Users   Your organization’s own users, when they are working outside your firewalls and are using their laptops or other Lync Server devices.

  • Federated Users   Users from companies you work with who also run Lync Server. To enable your users to easily contact these users, you create federated relationships with these companies.

  • Anonymous Users   Any other external users who are invited specifically by your users to join specific conferences. A meeting organizer in your company can send an email invitation for a conference to an external user. The email includes a link that the outside user can click to join the conference.

To enable any or all of these scenarios, you deploy an Edge Server to help enable secure communications between your Lync Server deployment and external users. The Lync Server solution using Edge Servers provides higher quality media than other solutions such as a virtual private network (VPN). For details, see Planning for External User Access.

Additionally, whether or not you deploy Edge Servers, you can enable users (either inside or outside your organization) to dial in from standard PSTN phones to join on-premises audio conferences. This is accomplished by deploying Lync Server dial-in conferencing.

Compatibility Among Meeting Types and Client Versions

Lync Server 2010 includes many improvements and enhancements to conferencing capabilities. For details about these changes, see New Conferencing Features.

However, these changes require you to be aware of some conferencing interoperability issues in Lync Server 2010. If you are going to have Lync Server 2010 interoperate with previous versions of Office Communications Server and its clients, you must be aware of the following issues:

  • Users using Lync 2010 cannot schedule Live Meeting online conferences, or modify any migrated meetings of this type.

  • Users using Lync 2010 who need to attend Live Meeting online conferences hosted on servers running Office Communications Server 2007 R2 must have the Live Meeting client installed on their computer (in addition to Lync 2010) to attend these meetings.

  • When Live Meeting online conferences are migrated to Lync Server 2010, meeting content does not migrate. If this content is needed, it must be uploaded again.

  • Users who are migrated from previous versions of Office Communications Server to Lync Server 2010 and who use Lync 2010 will receive a new assigned dial-in conference ID the first time they schedule an assigned dial-in conference meeting. They can use this new assigned dial-in conference ID to both schedule and attend meetings. The old ID will continue to work for previously scheduled meetings, but newly scheduled meetings are assigned the new ID.

  • Users in federated organizations who are using Microsoft Office Communicator 2007 or Microsoft Office Communicator 2005 clients cannot join Lync Server 2010 meetings in your organization unless the admission type for the meeting is set to Everyone. Federated users cannot join closed (company and invitation-only participants) meetings or meetings locked by the organizer, unless they use a Lync 2010 client.