It’s been a while since I installed the little Portech MV-370 GSM gateway. It sits in the office IT stack and does what it does. When I’m traveling it lets me call home using my unlimited mobile-to-mobile minutes. It also backs up our IP-based home & office phones. If both the Comcast Cable modem and Covad DSL are out the we can route calls out via T-Mobile.
The Gigaset cordless phones support enough accounts that this is easy, just add #6 to the number to specify dial using the GSM trunk. The GSM gateway is the 6th account on the Gigasets. We don’t even need a local Asterisk system to make it possible.
Remembering back to the installation of the GSM gateway, I converted my T-Mobile account from an individual plan to a family plan, with the gateway device becoming the second line on the account. I dropped my number of minutes but the monthly carrying cost was the same. It seems like a good idea since the use of mobile-to-mobile minutes to call home was going to reduce my need for minutes in the end.