[Asterisk-Users] Re: Open Ports

[Norman Zhang]

Tom Ivar Helbekkmo wrote:
>>I guess the first few packets from them to you might get dropped
>>because they don't match an "established" outbound connection, but
>>as soon as you start sending packets to them, your firewall will
>>allow two-way flow...
> 
> That's the trick, yes.  It works because RTP streams look as if they
> are bidirectional, so as soon as the first outgoing packet has been
> transmitted, the incoming stream is permitted.

I like your setup. I guess this will reduce some malicious incoming 
attack. Does performance suffers from this? Do I need canreinvite=yes?

Regards,
Norman Zhang