OCS 2007 R1/R2 Remote Access Configuration Guide

Rick Varvel has published a very detailed and comprehensive guide on how to configure Remote Access for OCS 2007 R1 and R2. Well worth reading.

Please take a look at it here https://blogs.technet.com/rickva/archive/2009/04/09/ocs-2007-r1-r2-remote-access-configuration-guide.aspx