Must the ports that use cos for qos be a trunk?

[teru-lei]

Hi all,

Somebody tell me that the switch port in access mode can not recognize the tag of 802.1q. If that is true, the access mode ports also can not recognize the bits of cos in 802.1q. In this points, if I want to config qos with cos in 3550, I must config the ports in trunk mode or dynamic mode. But that also is a problem, for I can not seperate VLANs in the switch. Any body has idea?

Thank You!

Best Regards

Teru Lei

[donewald]

Teru,

You can use the 802.1p COS fields to do this (Voice Vlan Feature) with an access port. Please see the following URL in the "Configuring Ports to Carry Voice Traffic in 802.1P Priority-Tagged Frames" section.

http://www.cisco.com/en/US/partner/products/hw/switches/ps646/products_configuration_guide_chapter09186a0080115951.html

Hope this helps you,

Don