Deploying Microsoft Lync Server 2010 Edge Server can be a daunting task. Installing the software is straightforward, but getting every functional element of all the ancillary components configured properly is a challenge. Before the deployment is fully functional you need to solve issues such as firewalls, network capacities, reverse proxy, DNS, routes, certificates, and so forth. This troubleshooting checklist was developed to facilitate a smooth deployment of Edge Server.
Read more at source: http://blogs.technet.com/b/nexthop/archive/2011/12/07/useful-tips-for-testing-your-lync-edge-server.aspx