Grandstream Networks UCM6510 IP PBX User Manual page 238

RTP Hold Timeout
Trust Remote Party ID
Send Remote Party ID
Generate In-Band Ringing
Server User Agent
Send Compact SIP Headers
Add "user=phone" to URI
Firmware Version 1.0.1.12
This setting doesn't apply to calls on hold.
When the call is on hold, if there is no RTP activity within the timeout (in
seconds), the call will be terminated. This value of RTP Hold Timeout
should be larger than RTP Timeout. The default setting is no timeout.
Configure whether the Remote-Party-ID should be trusted. The default
setting is "No".
Configure whether the Remote-Party-ID should be sent or not. The default
setting is "No".
Configure whether the UCM6510 should generate inband ringing or not.
The default setting is "Never".

Yes: The UCM6510 will send 180 Ringing followed by 183 Session
Progress and in-band audio.

No: The UCM6510 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 UCM6510 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 UCM6510.
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".
UCM6510 IP PBX User Manual Page 236 of 277