Allow guest calls, Figure 7: ivr dial trunk – Grandstream UCM6100 Security Manual User Manual
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UCM6100 Security Manual Page 13 of 23
Figure 7: IVR Dial Trunk
We recommend to disable “Dial Trunk” option unless the risk associated with it is clearly understood or the
PBX administrator intentionally configures it to do so for specific reasons. If it has to be enabled, please
con
figure the “permission” as secure as possible to restrict the authorized callers to be known users.
For more information about IVR permissions, please refer to IVR PERMISSION section in white paper:
ALLOW GUEST CALLS
“Allow Guest Calls” option can be found on web GUI->PBX->SIP Settings->General page.
We highly
recommend NOT to turn
on this option for any deployments. Enabling “Allow Guest Calls” will stop the
PBX from authenticating incoming calls from unknown or anonymous callers. In that case, hackers get the
chance to send INVITE to UCM6100 and the UCM6100 will place the call without authentication. This can
result in high toll charges.
The administrator might also want to check CDR regularly to make sure there is
no suspicious calls in the early stage of deployment.