Grandstream Networks DP750 Administration Manual page 51

Caller Request Uses session timer when making outbound calls if remote party supports it.
Timer Default is No.
Callee Request Uses session timer when receiving inbound calls with session timer request.
Timer Default is No.
Force Timer Uses session timer even if the remote party does not support this feature. Selecting
"No" will enable session timer only when the remote party supports it.
Default is No.
To turn off Session Timer, select "No" for Caller Request Timer, Callee Request
Timer, and Force Timer.
UAC Specify Specifies which end will act as refresher for outgoing calls:
Refresher
Default is Omit
Specifies which end will act as refresher for incoming calls:
UAS Specify
Refresher
Default is Omit
Force INVITE Uses INVITE message to refresh the session timer.
Default is No.
SIP Settings - Security Settings
Validate Incoming Defines whether incoming messages will be validated or not. Default is No.
Messages
Check SIP User ID Checks SIP User ID in the Request URI of incoming INVITE; if it doesn't match the
for Incoming INVITE base SIP User ID, the call will be rejected. Direct IP calling will also be disabled.
Default is No.
Accept Incoming Checks SIP address of the Request URI in the incoming SIP message; if it doesn't
SIP from Proxy match SIP server address of the account, the call will be rejected. Default is No.
Only
Challenges the incoming INVITE for authentication with SIP 401 Unauthorized
Authenticate
Incoming INVITE message. Default is No.
Authenticate Server Checks server TLS certificate to ensure that common name matches the configured
Certificate Domain SIP server. Default is No.
Authenticate Server Checks server TLS certificate to ensure that it is authorized by a known certificate
Certificate Chain authority. Default is No.

UAC: The base station acts as the refresher.

UAS: Callee or proxy server act as the refresher.

UAS: The base station acts as the refresher.

UAC: Callee or proxy server act as the refresher.
DP750/DP720 Administration Guide
Version 1.0.11.4
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