SIP2.0 401 Unauthorized response when dial 7777 to Asterisk

sip 7777The device state identifier for a particular device is typically very similar to the device name. For example the device state identifier for SIP6001 would be SIP6001, for conridge 7777 itWhen I call from a GSM cell phone, my TG100 GSM gateway answers and dials extension 7777 (confured as a hot on TG100) to asterisk server