;)
Friday
Sep212012
BUG CSCtt38270: 7925 sometimes takes 1+ second to respond to WPA M1 key message
Friday, September 21, 2012 at 10:54AM Heads up if you're having wireless voice issues with 7925 handsets with WPA2/PSK. Problems with roaming, gap in voice bug.
| 7925 sometimes takes 1+ second to respond to WPA M1 key message |
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| Symptom: A wireless phone call may experience a voice gap of 1.5 - 2 seconds when it roams if using WPA2-PSK. Conditions: 7925G is configured to use WPA2/AES PSK. Workaround: Configure some key management method to avoid performing a full WPA2 key exchange at each roam time. For example, EAP with CCKM, or static WEP. If using PSK, then reducing the WPA key retransmission timeout (e.g., on a WLC, via "config advanced eap eapol-key-timeout 250", may ameliorate the problem somewhat (e.g. bring the outage duration down from 2.5 to 1.7 seconds.) 1.4.3ES.1 containing the fix for CSCtz48689 may be helpful as well. Further Problem Description: A wireless packet capture, or a "debug client" on the WLC, will show that the WLC/AP transmit the M1 key message to the phone (and the capture shows that the phone ACKs it), but the phone does not send its M2 key. So the WLC/AP have to retransmit the M1 key, till finally the phone responds. |
Status  Terminated Severity 3 - moderate Last Modified In Last 2 weeks Product Cisco Unified IP Phone 7900 Series Technology Wireless, Mobile 1st Found-In 1.4(2) 1.4(1.1.1.7) |
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Reader Comments (1)
We worked with TAC on this one for a bit. They confirmed as best they could this is all flavors of PSK - WPA1/2 TKIP/AES. We have our EAPOL key timers at 250 ms by design already and when we saw this behavior it took the phone about 450 ms or so to roam. Not great for voice quality but better than a second or more.
Tac said the BU was not able reproduce this and they did not have a lot of resources committed to fixing it. We were planning on moving to 1X and cckm any way so we are moving that timeline up.