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Samarcande,

That's exactly right. I read some internal Cisco docs on this, and they said that the lightweight can't mark Ethernet frames with 802.1p CoS tags (which is actually 802.1Q CoS tags now) because an upstream (next hop) Cisco Ethernet switch wouldn't know how to handle them if it wasn't configured as a trunk (which lightweight APs rarely - if ever - are). They said it would produce an unknown result. I inquired for more detail, but, understandably, got none. This led me to inquire with countless other split mac architecture wlan vendors as to how they're doing upstream QoS. The overwhelming majority are doing ONLY WMM UP to DSCP mapping on the upstream at the lightweight AP. This means that in order to have real end-to-end QoS, we're going to have to have L2 Ethernet switches that are capable of reading DSCP headers in the IP header inside the Ethernet frame and acting on them appropriately. Luckily, such Ethernet switch exist (e.g. Cisco 2950 series). Note: This feature requires EMI code on the 2950 and similar switches.

Devinator