Anonymous Call Rejection

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.

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