@jwdicker wrote:
Has anyone noticed any issues with Microsoft Surface Pro's with "Power Save Aware Scan" in ARM enabled?
I noticed this post via Microsoft:
When an 802.11 wireless network adapter that is set to use power save mode wants to enter a sleep state, the adapter indicates this intention to the wireless AP. The adapter does this by setting the power save option in its packets or in the 802.11 frames that it sends to the wireless AP. In this scenario, the following behavior should occur:
1. When the wireless AP receives the frames that have the power save option set, the wireless AP determines that the client network adapter that sent the frames wants to enter a power saving state.
2. The wireless AP then buffers packets that are destined for the client network adapter.
3. When the radio of the client network adapter turns on, the client network adapter then communicates with the AP to retrieve the buffered packets.
This behavior enables the wireless network adapter to use less power and to wake up periodically at the correct time to receive network traffic from the AP.
If the wireless AP does not support this feature correctly, the wireless AP continues to send packets to the client network adapter even if the client network adapter radio is turned off. Therefore, these packets are lost. In this scenario, the symptoms that you experience may vary depending on the phase of the wireless connection in which these packets are lost.
jwdicker,
Power Save is part of the 802.11 standard (http://www.youtube.com/watch?v=uph5Sg1z81Y) and all enterprise access points support this. The power-save aware mechanism in the ARM profile is an addition to this and it should not affect standard 802.11 power save. With that being said, if all of your other clients are not having a problem, in general, the problem is not with your infrastructure or with power save in general. I would say open a support case to determine exactly what is going on with your specific client. New clients come along all the time and there is always fine tuning done on the drivers to determine what is wrong. Opening a support case will prevent you from chasing in the wrong direction. Hopefully other customers with the surface will chime in on what they found so that you can get some relief with your issue. The "show ap debug client-table ap-name <name of ap>" command will show you clients going in and out of power save to demonstrate that this is supported. Do you have a specific issue, or is this a question about what you read?
(Aruba3600) #show ap debug client-table ap-name AP-125-Home
Client Table
------------
MAC ESSID BSSID Assoc_State HT_State AID PS_State UAPSD Tx_Pkts Rx_Pkts PS_Qlen Tx_Retries Tx_Rate Rx_Rate Last_ACK_SNR Last_Rx_SNR TX_Chains Tx_Timestamp Rx_Timestamp MFP Status (C,R)
--- ----- ----- ----------- -------- --- -------- ----- ------- ------- ------- ---------- ------- ------- ------------ ----------- --------- ------------ ------------ ----------------
00:1a:1e:1d:c0:f1 3FEEF727-4ACE-4586-9817 00:1a:1e:20:82:f0 Associated WS 0x1 Awake (0,0,0,0,N/A,0) 1370565 2752724 0 46332 78 104 27 26 2[0x3] Sun May 26 11:16:07 2013 Sun May 26 11:16:07 2013 (0,0)
5c:da:d4:24:a9:9e CatchMe 00:1a:1e:20:82:e0 Associated None 0x2 Awake (0,0,0,0,N/A,0) 30628 37937 0 789 54 54 42 40 2[0x5] Sun May 26 11:15:46 2013 Sun May 26 11:15:46 2013 (0,0)
44:2a:60:c3:b8:fe CatchMe 00:1a:1e:20:82:e0 Associated M 0x4 Power-save (0,0,0,0,N/A,0) 1731 10879 0 26 65 65 31 31 2[0x5] Sun May 26 11:15:45 2013 Sun May 26 11:15:46 2013 (0,0)
10:bf:48:e8:1e:17 CatchMe 00:1a:1e:20:82:e0 Associated 0x1 Power-save (0,0,0,0,N/A,0) 15037 50328 0 256 65 65 36 37 2[0x5] Sun May 26 11:15:42 2013 Sun May 26 11:15:42 2013 (0,0)
e8:92:a4:96:6f:43 CatchMe 00:1a:1e:20:82:e0 Associated 0x3 Power-save (0,0,0,0,N/A,0) 17366 52154 0 17 65 6 52 50 2[0x5] Sun May 26 11:15:30 2013 Sun May 26 11:15:42 2013 (0,0)
UAPSD:(VO,VI,BK,BE,Max SP,Q Len)
HT Flags: A - LDPC Coding; W - 40Mhz; S - Short GI HT40; s - Short GI HT20
D - Delayed BA; G - Greenfield; R - Dynamic SM PS
Q - Static SM PS; N - A-MPDU disabled; B - TX STBC
b - RX STBC; M - Max A-MSDU; I - HT40 Intolerant
(Aruba3600) #