[asterisk-users] QoS & VPN

[Brent Davidson]

I've got multiple satellite office all linked back to the main office 
via VPN.  Each office has their own asterisk server which registers back 
to the main office's Asterisk server.  Each office also has a 1Mb 
downstream / 384k - 768k upstream connection.  The branches are using 
Speex for their connections back to the main office.  The issue I'm 
having is that there are times that I need to VNC in to machines at the 
various offices for tech support while the user is also on the phone.  
Unfortunately the VNC connection apparently takes priority and makes it 
impossible for me to understand anything the person on the phone is 
saying, although they can still hear me fine.

Our Main office uses a Cisco PIX 506 for the main firewall and VPN 
concentrator.  Each branch office used a Cisco 1700 series router with 
IPSec enabled in the IOS.  Is there any sort of QoS I can turn on on the 
main router or the branch routers to make sure the voice quality takes 
precedence over the VNC?  (Any example configs would be greatly appreciated)

Would I be better off routing the voice packets over the internet rather 
than the VPN, and could I safely do that without exposing the asterisk 
boxes to unnecessary security risks?  (At present all of our asterisk 
boxes are behind the firewalls and only talk to each other over the 
VPN.  All PSTN connection is done through TDM boards so they have no 
direct exposure to the internet.)

Thanks,
Brent Davidson