In Part 2 we built the raw components for a Lync deployment. Before we create Lync we first need a PBX system if we are going to use enterprise voice. The PBX chosen for this lab is Elastix 2.5 which is an open source pbx system available for download here: http://www.elastix.org/index.php/en/downloads.html
In order to process calls to and from the PSTN we will also need a hosted SIP account with an online SIP provider. For this lab I have chose to use SIPGATE as the sip provider, http://www.sipgate.co.uk
Please sign up for your own account with them. It is free to sign up and use the service for inbound calls. You can also make calls to freephone numbers without charge, so is perfect for testing a simple EV deployment with Lync.
This part assumes that Elastix has been installed to PBX01, configured with the IP address and you have your Sipgate account information.