Edge Planning Tool for Office Communications Server 2007 R2
The Edge Planning Tool for Microsoft Office Communications Server 2007 R2 provides settings for configuring your perimeter network based on information that you provide to the tool.
You can download the from here: http://www.microsoft.com/downloads/details.aspx?FamilyID=ec4b960c-3fe2-41bd-abdf-ae89cfcb8c6c&displaylang=en