1. Defining Your Requirements
The first big step in planning a deployment is determining what
features you plan to support. This greatly influences the overall
design, has a big impact on server roles that are deployed, and affects
infrastructure services such as the LAN and the WAN.
If you plan to enable web conferencing, which includes both document and application sharing, account for the following:
• Enable conferencing for the Front End pool in the Topology Builder.
• Account for increased network usage
for application sharing. The default throttling is 1.5 KB/sec for each
session and can be modified as needed.
• Build custom meeting policies if
there is a need to enable either application sharing or document
collaboration but a desire to prevent the other.
To enable audio and video conferencing, which in this type of
deployment includes PC-to-PC calls but not PBX integration, plan for
the following tasks:
• Enable conferencing for the Front End pool in the Topology Builder
• Account for increased network usage, typically 50 Kbps for audio and 350 Kbps for video
If requirements include supporting external users connecting to internally hosted conferences, consider the following tasks:
• Deploy Edge Servers in the topology.
• Properly protect access to the Edge Servers.
• Properly resolve the meeting URLs externally.
• Be sure users trust the certificates used on the Edge Servers to establish SSL connections.
• Decide whether federation will be supported.
Another decision, which must be accounted for, is whether it is
necessary to support legacy clients on Lync Server 2010. Each time a
client connects, its version is checked and compared against policies
to determine whether it can be used. Web-based connections attempt to
detect a local client and always offer the option of the web-based
client. This is an important decision because there are compatibility
limitations between various clients and back ends:
• Lync 2010 clients can neither schedule Live Meeting online conferences nor modify or migrate meetings of this type.
• Lync 2010 clients who need
to attend Live Meeting online conferences hosted on OCS 2007 R2 servers
must also have the Live Meeting client installed in order to
participate.
2. Planning Your Conferencing Topology
Conferencing can be deployed in either the Standard Edition of Lync
Server 2010 or in the Enterprise Edition. Topologies are simple in the
Standard Edition because, by definition, all roles are placed on a
single server. This is easy to plan because there are no options.
Deploying on Enterprise Edition, on the other hand, opens up several
options that must be considered.
Typically, you deploy on Enterprise Edition of
Lync Server 2010 to gain redundancy by running a given role on more
than one server and load balancing them to gain redundancy. Usually the
decision on deployment is on whether to collocate the A/V Conferencing
Server role with the Front End role. The decision point is usually on
user load. Typically for deployments of fewer than 10,000 users, it is
recommended to collocate the A/V Conferencing Server role with the
Front End role. For more than 10,000, it is recommended to separate the
roles (see Figure 1).
Additionally, in a noncollocated topology, an A/V Conferencing Server
can support up to 35,000 users. Going beyond this number requires
additional A/V Conferencing Servers. Also keep in mind that if the
reason for deploying on Enterprise Edition was to achieve redundancy,
strongly consider deploying an n+1 architecture so that loads can be
maintained if a server fails.
Figure 1 Configuration for AV Topology
When planning hardware for conferencing, install servers to handle
the load. Although Microsoft’s recommendations typically call for a
collocated A/V Conferencing and Front End Server to support 10,000
users, that is based on the following hardware:
• Eight processor cores (dual quad-core or quad dual-core)
• 16 GB RAM
• Multiple 10,000 RPM disks or solid state hard drives
• Dual Gigabit Ethernet adapters
Regardless of whether the A/V Conferencing and Front End
roles are collocated, the configuration can run on Standard Edition of
either Windows 2008 x64 or Windows 2008 R2.
3. Planning for Clients and Devices
There are several clients for Lync Server 2010 in which to plan.
Administrators have the ability to limit which clients can connect so
that users can only use a client that is currently supported. This
simplifies troubleshooting because it’s possible to prevent unexpected
clients from connecting. The current list of clients includes
• Lync 2010—The primary Windows client
• Lync 2010 Attendee—The web-based plug-in for clients that don’t have a full client
• Lync Web App—The web-based client that provides the primary features
• Lync Server 2010 Attendant—The integrated call management application, typically used by a receptionist for managing multiple lines and for routing calls
• Lync 2010 Mobile—The client for smart phones
• Lync 2010 Phone Edition—The client running on traditional handsets
• Online Meeting Add-in for Lync 2010—The client that provides integration with Outlook for meeting management
Another item to plan for on the topic of clients is the deployment
of clients to end users. The two supported methods are to either deploy
the .exe version of the client, or to extract the .msi from the
executable and deploy this through Group Policy. It’s typically
preferred to deploy the executable version through some other
application deployment method because the .exe version performs the
following tasks that the .msi doesn’t:
• Automatically performs prerequisite checks
• Installs Visual C++ components and Silverlight if missing
• Uninstalls Lync 2010 Attendee
• Notifies the user about Media Player 11 requirements
• Uninstalls legacy OCS clients
