Though about GSM, if you want to learn more: * http://osmocom.org http://osmocom.org * http://www.youtube.com/watch?v=xOp_wtsHAe8 http://www.youtube.com/watch

Though about GSM, if you want to learn more: * http://osmocom.org http://osmocom.org * http://www.youtube.com/watch?v=xOp_wtsHAe8 http://www.youtube.com/watch?v=xOp_wtsHAe8 * http://www.youtube.com/watch?v=_0LCgxe24Po http://www.youtube.com/watch?v=_0LCgxe24Po * http://www.youtube.com/watch?v=9cBJV3yTaQo http://www.youtube.com/watch?v=9cBJV3yTaQo * http://www.youtube.com/watch?v=9cBJV3yTaQo http://www.youtube.com/watch?v=9cBJV3yTaQo Your phone has GSM, even if you're only on 3G or 4G networks though (unless it's a pure CDMA phone) - and the concepts are anyway quite similar in 3G/4G networks an phones.