Hi All, In the past month we have uncovered a couple of strange issues with Intel 802.11n client drivers. Our testing was done using a Intel 5300 client with Intel supplicant and Windows Zero Config in open air. Issue #1: The Intel driver version 13.0.0.107 - In 2.4 and 5 GHz, an up stream ping (client to AP) from a short distance sometimes drop. This was seen when MCS rates were enabled as supported rates. This issue goes away when upgraded to Intel driver 13.1.1.1. Issue was not seen when only 802.11a/b/g rates were enabled. The cause of this issue has to do with a strange Intel implementation that repeatedly negotiates and tears down Block Ack agreements if the AP has no packets to aggregate. During the negotiation process the client seems to be dropping packets. Bottom Line: Please upgrade the driver to version 13.1.1.1 or higher if you see this issue. Issue #2: Intel driver version 13.0.0.107 and 13.1.1.1- In 2.4 GHz, Intel client will not aggregate packets to MOT AP (when it is far from the AP) whereas it will aggregate packets with Cisco AP at the same distance. As the client is brought closer even a few feet away the aggregation displays a periodic behavior. When running a TCP throughput test using Chariot you would see a lot of peaks and valleys. Again there is a strange implementation on Intel client side where if you enable short preamble (yes short pre-amble not short guard) Intel client will aggregate packets to MOT AP. So in any throughput tests in 2.4 GHz with Intel clients, please make sure that short pre-amble is enabled. Please be mindful that there might be old legacy clients that will not associate if short pre-amble is enabled. We are considering possible solutions to this interoperability issue. Bottom Line: Thankfully a simple workaround - Enable short preamble in 2.4 GHz radio - exists till then. Thanks, Rajiv