Using IIS ARR 3.0 on Windows Server 2012R2 as a Reverse Proxy for Lync Server 2013 – the UC Guys
I have reliably been using IIS ARR as a low cost replacement for ISA/TMG (Free with Windows Server!) for some time now however I recently had a customer that had provisioned Windows Server 2012R2 so I decided to use IIS…

http://www.ucguys.com/2014/08/using-iis-arr-30-on-windows-server-2012r2-as-a-reverse-proxy-for-lync-server-2013.html