Hello there, I have setup the alwaysauthreject=yes to /etc/asterisk/sip_general_additional.conf and I want to set up rules to allow only selected ip to make sip registration. I try to add deny=0.0.0.0/0.0.0.0 permit=66.19.xx.xx/255.255.255.255 to the sip_general_additional.conf, but it did not block the registration. under the sip.additional I tried  host=66.19.xx.xx/255.255.255.255 also not do the trick to prevent  to register from another ip? Please advice what am I missing here? appreciate your help.