One (pair of) Loadmaster(s) is deployed for load balancing all of the Internal Lync Servers (including the internal facing Lync Edge Server Interface) and one (pair of) Loadmaster(s) for load balancing all of the External-facing interfaces for Lync Edge Servers.

Note: This deployment option departs from the Microsoft recommended standard, as described in http://technet.microsoft.com/en-us/library/gg398478(v=ocs.14).aspx, and may cause some issues in certain network configurations.