QoS ASA5505 for SIP Traffic

[Steven Tolzmann]

Hi all,

My company has been having trouble lately with VOIP phones cutting out, and garbled transmissions. I wanted to implement QoS to possibly improve call quality, but only want to have 2 groups:

1) SIP

2) Best Effort

We use exclusively ASA5505s, and we have a Hub & Spoke VPN Network setup, with the VOIP Box (Trixbox) being situated on the Hub network. It has a SIP Trunk to a VOIP Provider on the internet.

We have AASTRA Phones at each site, and they use a Split-Tunnel L2L VPN system to connect back to the HQ (Hub).

I made a crude drawing of our network (attached)

What is the basic configuration to prioritize VOIP Traffic over all VPN Links, and from the Hub to the Internet? I could not find any helpful configuration examples on the internet.

Thanks in advance!

-Steve Tolzmann

[Brian Meade]

http://www.cisco.com/c/en/us/support/docs/security/asa-5500-x-series-next-generation-firewalls/82310-qos-voip-vpn.html has some examples for setting up the priority queue for DSCP EF traffic assuming the DSCP taggings are making it through the network to the ASA.