QoS for Voice in VPN

tabbott · ‎07-07-2003

We have a cable modem with a 831 router behind that creating a GRE tunnel with QoS on the tunnel and a priority queue for voice. If other systems are trying to access the internet from the 831 but not in the tunnel will the priority queue still place the traffic out the interface first or will the priority queue only place the traffiic out first over the other traffic in the tunnel?

j_rios · ‎07-07-2003

Hello

http://www.cisco.com/pcgi-bin/Support/browse/index.pl?i=Technologies&f=1387

J.R

dgoodwin · ‎07-09-2003

I think the answer depends on what kind of queueing you are doing on the outbound Ethernet interface to the cable modem.

If you are doing PQ on the Ethernet interface connected to the cable modem, and the voice traffic is already inside the GRE tunnel by the time it wants to leave the interface, then you would need to prioritize GRE traffic over the rest of the traffic, and hopefully all you have inside the GRE tunnel is voice traffic that needs to be prioritized.

Additionally, you'll probably want to use generic traffic-shaping to limit the amount of kbps you send outbound to the cable modem, as we are able to queue packets if needed, whereas the cable modem will not.