Microsoft Lync Server 2010 Capacity Calculator
A spreadsheet for calculating a user’s hardware requirements based on information that the admin supplies about number of users, types of communication, and expected traffic. Includes a Microsoft Word document explaining the tool and how to use it.
Download from here.
Lync Server 2010, Stress and Performance Tool
The Lync Server 2010 Stress and Performance Tools (LSS) can be used to prepare, define and validate performance targets of user scenarios offered by on-premise Lync Server 2010 deployment. LSS includes multiple modules and can simulate simultaneous users on one or more Lync Servers. More detailed information can be found in the documentation provided within the installation package.