Figure 18: Default Blocking Rules; Figure 19: Whitelisted Devices - Grandstream Networks GSC35 Series User Manual

On the screenshot below, only number 1001 is allowed to call GSC3510/GSC3505:
As soon as a SIP call is received by the GSC3510/GSC3505, it first checks if the Caller ID number is
allowed on the Whitelist and then answers automatically.
Notes:
•
GSC3510/GSC3505 is an intercom system and auto-answers all whitelisted numbers.
•
By default, GSC3510/GSC3505 plays a Warning tone when auto answering incoming calls, this
warning tone can be disabled under Account → Account X → Call Settings, "Play Warning Tone
for Auto Answer Intercom".

Figure 18: Default Blocking Rules

Figure 19: Whitelisted Devices

GSC35XX Series User Manual
Version 1.0.0.15
P a g e | 25