Overview
Anonymous Call Rejection can be used to protect against anonymous SIP attacks. However, it can block restricted numbers as well. If used on an open/public facing network, you may want to enable this option to stop users from calling the phone by IP address. If you are behind a firewall, this setting is most commonly disabled as calls should not be able to get to the phone direct, they should be routed through your PBX.
Setting Anonymous Call Rejection
You can set the Anonymous Call Rejection using the PBX EndPoint Manager.
Go into End Point Manager in your PBX and select the Sangoma brand in the menu.
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