While most users of FreeSWITCH will use SIP (and thus
mod_sofia), there are other ways for FreeSWITCH to communicate with the world. Here are brief descriptions of three methods that you may wish to investigate further.
Skype and GSM endpoints
Not everyone has the budget to buy hardware or services to connect to the Skype and GSM (Global System for Mobile Communications) networks, especially when first learning a new technology. FreeSWITCH has an alternative to offer to those willing to do a little work: a pair of endpoints (that is, channel drivers) that allow inbound and outbound voice calls and messaging (chatting, SMSs) in the cheapest possible way.
mod_gsmopen support full integration with all the ...