I just put together a blog on upstream QoS for the WLC. That should be out within the next couple weeks. I'm also going to put together some more on downstream QoS, TSPEC, non-WMM, and rate-limiting.
For now, know that the QoS Profile itself (without the 802.1p value) determines the maximum DSCP value coming from the AP to the WLC. That mapping occurs at the AP and that is where the "AVVID" conversion takes place. The 802.1p value determines the maximum value to map the outer LWAPP DSCP to the outer DSCP and CoS going out from the WLC. If it is set to "None," then the DSCP and CoS will be "0." For the question on "1 and 2" being worse than "0," that is correct for 802.11e. It is also true (if queues are set to the defaults) for CS1 and CS2 as opposed to DSCP 0. Just because they are greater than 0 doesn't make them more important. Also, for question 2, my gut says yes, but I haven't tried that configuration. Can you test it and use Wireshark to verify? Jason Boyers - CCIE #26024 (Wireless) Technical Instructor - IPexpert [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Kristján Ólafur Eðvarðsson Sent: Tuesday, February 08, 2011 7:02 PM To: [email protected] Subject: [CCIE Wireless] 1. Two questions about QoS (Stalder Dominic) Let me try this one Dominic. 1. I would say that zero is no the maximum value. I gather you want the higest "value" that a packet can have. For the QOS mapping table 802.1p 0 would be DSCP 0, or Best effort. So Max would be 7 (lwapp control) or 6 (voice platinum) Here is a very good reference on the QOS table mappings in wireless: http://www.cisco.com/en/US/tech/tk722/tk809/technologies_configuration_examp le09186a00807e9717.shtml#intro BUT if you look at the help in the WLC gui just below the value. it says: * the value 0 (zero) indicates that the feature is disabled. So putting it to zero would not mark anything! right ? What I don´t understand, and would like to get some feedback on is: If you look at the table 802.1p values. 0 is marked is Best effort (WLC Silver) but 1 and 2 values are there for "background" in 802.1p. 802.11e "Background" is worse than Silver (right?), so I don´t understand why the table claims 1 and 2 for Background and 0 for silver. Anyone ? Regarding the "What happens.." section of you question. When you set value of 6 in the WLC. You actually get mapped to value 5. So from what you chose you always auto mapped one lower AVVID 802.1p value. So in WLC use 6 when you want AVVID 5. There isn´t anything that explains it in the GUI you just have to know. So i guess, even though the value input is for 802.1p in the WLC, you want to think from the 802.11e pespective. That is ask your self "what 802.11e UP (user priority) value am I going to map from ?" That at least helps me... This video with Jerome explains it preety well.http://www.youtube.com/watch?v=5AHpIAEu3uQ&feature=related 2. I don´t have clue here. We better investigate. But I hope someone else knows :D regards. Krisjan ---------------------------------------------------------------------- Message: 1 Date: Tue, 8 Feb 2011 08:59:43 +0000 From: Stalder Dominic <[email protected]> To: "[email protected]" <[email protected]> Subject: [CCIE Wireless] Two questions about QoS Message-ID: <c976c48b.2e76%[email protected]> Content-Type: text/plain; charset="us-ascii" Hi there I have two questions about QoS on the controllers: 1. If the 802.1p value under QoS profiles (for example Platinum) is set to 0, will all LWAPP data pakets be marked with a DSCP value of 0. As I understand, this is the maximum value, that a packet can have, if it falls within this profile. But what happens, when I set the value to 6 (as recommended) and a WMM client has a 802.11e UP value of 5. Will the LWAPP packet be forwarded with DSCP 5, I think, or am I wrong? If it would be a non-WMM client, the value would be 6, right? 2. Can QBSSv1 and QBSSv2 coexist? I think the can coexist on the controller, but they CANNOT coexist within one WLAN. What would you say? Thanks and best regards Dominic _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
