Grandstream Networks UCM6102 User Manual page 198

Generate In-Band Ringing
Server User Agent
Send Compact SIP Headers
Add "user=phone" to URI
Firmware Version 1.0.7.11
Configure whether the UCM6100 should generate inband ringing or not.
The default setting is "Never".

Yes: The UCM6100 will send 180 Ringing followed by 183 Session
Progress and in-band audio.

No: The UCM6100 will send 180 Ringing if 183 Session Progress
has not been sent yet. If audio path is established already with 183
then send in-band ringing.

Never: Whenever ringing occurs, the UCM6100 will send 180
Ringing as long as 200OK has not been set yet. Inband ringing will
not be generated even the end point device is not working properly.
Configure the user agent string for the UCM6100.
If enabled, compact SIP headers will be sent. The default setting is "No".
If enabled, "user=phone" will be added to URI that contains a valid phone
number. The default setting is "No".
UCM6100 Series IP PBX User Manual Page 196 of 233