topic Re: QoS for voice tagged traffic in Wireless

QoS for voice tagged traffic

dazilk — Sun, 04 Jul 2021 17:47:03 GMT

I am trying to confirm my assumption that given voice traffic arriving at an AP or wireless bridge is already tagged with COS (and TOS) precedence, the wireless device will properly deal with it by default.

It appears from the documentation, but isn't explicitly stated, that the only QoS configuration required is to classify and tag (COS) packets. If they are tagged already, no configuration is required.

Is this correct?

Also, are COS precedence values preserved across a wireless bridge link, or must they be re-tagged at the far end?

Re: QoS for voice tagged traffic

ebreniz — Thu, 19 May 2005 17:26:28 GMT

Some configs are given below.

http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_configuration_example09186a00801a90d3.shtml

http://www.cisco.com/en/US/products/hw/phones/ps379/products_white_paper0900aecd800f6d97.shtml

Re: QoS for voice tagged traffic

dazilk — Thu, 19 May 2005 19:37:37 GMT

Thanks for the links, but they don't really address the question. I am looking for information specifically about the 1310 bridges used to create a point-to-point link between two sites both with 'wired' ip phones.

It appears that nothing needs to be set on the bridges to prioritize traffic that is already tagged with 802.1P COS values. I am looking for verificatation that this is a correct assumption.

Re: QoS for voice tagged traffic

cscherb — Sat, 03 Dec 2005 06:09:17 GMT

That's exactly my question to. Would be very interested in the answer.

Re: QoS for voice tagged traffic

stoidis — Mon, 05 Dec 2005 12:36:56 GMT

I'm looking forward for an answer too 🙂

Re: QoS for voice tagged traffic

mheusinger — Sun, 18 Dec 2005 21:53:36 GMT

Hi there,

in "Configuring QoS" of the Aironet 1310 Configuration Guide

http://www.cisco.com/en/US/products/ps5861/products_configuration_guide_chapter09186a00804ed713.html

it reads:

"Precedence of QoS Settings

When you enable QoS, the access point/bridge queues packets based on the Layer 2 class of service value for each packet. The access point/bridge applies QoS policies in this order:

1. Packets already classified—When the access point/bridge receives packets from a QoS-enabled switch or router that has already classified the packets with non-zero 802.1Q/P user_priority values, the access point/bridge uses that classification and does not apply other QoS policy rules to the packets. An existing classification takes precedence over all other policies on the access point/bridge.

Note Even if you have not configured a QoS policy, the access point always honors tagged 802.1P packets that it receives over the radio interface."

Hope this helps

Martin

Re: QoS for voice tagged traffic

cscherb — Sun, 18 Dec 2005 22:54:08 GMT

Thanks - I hoped it would work likt this.

Additionally I enabled "AVVID Priority Mapping" in advanced QoS Configuration as Voice in AVVID is usully marked with DSCP EF which in default is translated by Catalyst Switches to CoS 5.

My understandig of this function is the Cos 5 and 6 is handled as Voice (jitter <= 30ms) - without this setting, only Cos 6 is handled as Voice and Cos 5 is handled as Video (jitter <= 100ms).