I'm using
<param name="apply-nat-acl" value="my_nat"/>
<param name="nat-options-ping" value="true"/>
in my SIP profile in order to make Freeswitch ping every phone registered to it.
This works well for keeping phones on remote LANs reachable.

My_nat ACL is defined as following:
    <list name="my_nat" default="allow">
    </list>
That is, it allows everybody.

Question: am I making my system insecure by doing so?
I believe "No" since ACL list "my_nat" is only used by appl-nat-acl parameter,
but I don't know FreeSWITCH well enough to grantee that nothing else is affected.
E.g. does anything else change if phone is considered NATed / non-NATed?

Regards,
Victor