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Specifying priority for management frames?

DISCUSSION Ben Greear 1 participant 4 messages Sep 5, 2013 – Sep 9, 2013

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Ben Greear

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While debugging a problem with group-rekeys, we noticed that the sniffer (on external machine) reported management packets are sent in the best-effort QoS queue.

It seems to me that these should be in the VO queue instead, or at least we should be able to specify the queue in supplicant when sending the frames?

Thanks,
Ben

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Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com
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#1 lore raw
Quoted 5 lines · Ben Greear

While debugging a problem with group-rekeys, we noticed that the sniffer (on external machine) reported management packets are sent in the best-effort QoS queue.

It seems to me that these should be in the VO queue instead, or at least we should be able to specify the queue in supplicant when sending the frames?

Hrmm, actually it appears the mac80211 layer tries to send on VO. Maybe some of my hackings are messing this up...I'll go dig deeper.

Thanks,
Ben

Signature · 2 lines
Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com
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#2 lore raw
Quoted 10 lines · Ben Greear
Quoted 5 lines · Ben Greear

While debugging a problem with group-rekeys, we noticed that the sniffer (on external machine) reported management packets are sent in the best-effort QoS queue.

It seems to me that these should be in the VO queue instead, or at least we should be able to specify the queue in supplicant when sending the frames?

Hrmm, actually it appears the mac80211 layer tries to send on VO. Maybe some of my hackings are messing this up...I'll go dig deeper.

I've dug a bit deeper, but not all the way I guess.

When I sniff on a separate machine, the EAP packets still show QoS being 'Best Effort' in wireshark.

UDP data packets sent with proper IP TOS show up in VI or VO as specified.

So, I think this means that either the EAP packets are not actually going out the VO queue, or they are somehow missing some wifi QoS config in their header.

I just tested this with the latest wireless-testing tree, totally un-modified.

The sniffer is running my standard set of patches, but I doubt that matters since it does properly show QoS on UDP packets.

I'll go look to see if I can figure out where the wifi frame TOS bits are configured..but if someone has suggestions, let me know!

Thanks,
Ben

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Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com
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#3 lore raw
In reply to Ben Greear
Quoted 5 lines · Ben Greear

While debugging a problem with group-rekeys, we noticed that the sniffer (on external machine) reported management packets are sent in the best-effort QoS queue.

It seems to me that these should be in the VO queue instead, or at least we should be able to specify the queue in supplicant when sending the frames?

This is a problem in supplicant/hostapd. They were not setting the socket priority to (256 + 7) as they should have been doing. With that fix, packets on the air show the proper 'VO' QoS queue.

I posted patches to fix supplicant/hostapd to the hostapd mailing list. Hopefully they are proper patches...at least they seem to work for me.

At least the hostapd side of this seemed to slip in with the addition of the new non-monitor eapol tx status feature.

Thanks,
Ben

Signature · 2 lines
Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com