Allowing anonymous & guest

Just to check connectivity in all my trunks, i’ve set :

Allow SIP Guests YES
Allow Anonymous Inbound SIP Calls YES

in “asterisk SIP settings”

now, to be safer (some strange unknown failed tries logged from internet) I set both to NO

As first result also regular calls from isdn gateway (cisco router) trunk are blocked as shown by asterisk console.

This trunk was simply configured as :

host=172.16.217.110 (the IP of gateway)
type=peer

since the regular VoIP ISP trunk works OK as well with anonymous restrictions, I noted in this trunk the setting :

insecure=port,invite

I copied this line into isdn gateway trunk config and it started again to receive calls.

Is this last addiction enough to restore full functionality of incomig calls on SIP trunks ??

Thank you