Recently I moved my office from one location to another.  The prior location had a Comcast SMC modem,  and I was hosting my Turbo Meeting  Appliance in-house.  A-records were entered for my new IP address for my new location at http://help.techanywhere.net .  My new location was equipped with Comcast’s new Cisco Xfinity stand up modem.  I could reach my site from the outside, but was unable to reach the global IP from my internal network.  I could reach the appliance if I used the internal address, but this was not allowing me to utilize the hyperlink or to access my utilities without an internal address.  I tried for hours to figure the configuration out that would allow for the loopback.  I knew it wasn’t a DNS issue.  I called several friends in the industry and they couldn’t come up with any answers or offer any similar problem that they were aware of.  I called Comcast and told them the problem.  I evidently was lucky enough to get a tech that knew what it was.  This Cisco modem has a configuration on the back end that allows Comcast to configure this feature which denies the loopback by default.  The tech simply allowed it in the modem and restarted.  Everything works now.  Hopefully this will help someone else to save a lot of time trying to change every configuration inside the modem.  Only Comcast can reach the backend of this modem.