Hi, I am dealing with an Asterisk server behind NAT that is not set properly, with its external IP
I am asking them to fix it on there side but I am curious to know if there is a way to deal with this implemented in FS

Freeswitch --> Internet --> NAT --> Asterisk

In the "200 OK" returned by Asterisk  as the private IP in the "Contact" header
FS is returning ACK to the private IP.

INVITE --->
<--- 200 OK
---> ACK
<--- 200 OK
---> ACK
<--- 200 OK
---> ACK
....

It seems   <param name="apply-nat-acl" value="rfc1918"/><param name="aggressive-nat-detection" value="true"/>
does

It seems sip-force-contact could patch the problem caused by the remote gateway
Is there a way to us sip-force-contact with gateway instead of an entry in the directory ?