[asterisk-users] Tuning a ZyWALL for Asterisk

[Ed Pastore]

I understand this question is over-broad, but hopefully you can have  
patience with a newbie and toss me a bone...

I am in the testing stage of deploying Asterisk. I have successfully  
configured it to work behind the NAT of my ZyXEL ZyWALL 35 firewall.  
However, I think there is a lot of tuning I can do to get better  
reliability, bandwidth management, and maybe QoS from the firewall. I  
have some clues as to how to do some of this, but both telephony and  
routing are not strong points for me (I mostly work on systems,  
servers, and LANs).

Is there any sort of reference material that will guide me in setting  
up my ZyWALL for VoIP? I don't see much help from ZyXEL, and I only  
see scattered posts around the net, but I know a lot of people are  
using ZyWALLs with Asterisk.

If there isn't a reference, then can anyone chime in with some  
particulars on what you've done?

Any hints would be greatly appreciated. Thanks!