Hi
I'm using version: kamailio 5.1.2 

I have strange issue with auth_challenge

kamialio works as NAT handler. When Register comes kamailio handles nat and save original ip:port at the received field in location table

I found that when local port in contact is different than external port reply 407 on INVITE comes to externalip (from received) : internalport(from contact)
And never reaches destination

for exmaple
Register comes from 
192.168.1.10:50555

Kamailio saves at the Received
12.1.1.12:1030

but when invite comes form 12.1.1.12:1030 kamailio sends reply to 
12.1.1.12:50555

i don't think that this is an issue in kamailio source code but i can find where i can configure it

_______________________________________________
Kamailio (SER) - Users Mailing List
sr-users@lists.kamailio.org
https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users