[asterisk-users] IAX2 NAT issues

[Perssy Llamosas]

Hello,

I am playing around with IAX2 and I have encountered a problem trying to 
setup an asterisk box through NAT using IAX2.

This is the problem:

Asterisk box => Advanced Firewall => Internet => User's router => User

The user can register, the server can answer, calls can be made.

Asterisk box => Very simple router => Internet => User's router => User

User's packet reach the server, the server cannot reply because the udp 
connection is lost, several RX retry TX retry, user is unable to call.

In both cases the firewall and the router are forwarding the port 4569 
to Asterisk, user's router is not forwarding anything, the user has 
qualify=yes to maintain the connection open but the very simple router 
will drop the connection before Asterisk can reply to the packet.

So I ask the list: Is there a way to overcome this problem? Udp 
connection timeout in Asterisk? Should I get a new router?

Thanks,

PLL.