On Thu, Dec 30, 2010 at 9:54 PM, Chin Shi Hong <cshong87@xxxxxxxxx> wrote: > On Fri, Dec 31, 2010 at 7:27 AM, Christian Lamparter > <chunkeey@xxxxxxxxxxxxxx> wrote: >> On Thursday 30 December 2010 16:55:18 Chin Shi Hong wrote: >>> Dear All, >> >> Hello, >> >>> Wireless adapter model: TP-LINK WN821NC (USB 300Mbps Wireless N adapter) >>> Output of lsusb: Bus 001 Device 007: ID 0cf3:1002 Atheros >>> Communications, Inc. TP-Link TL-WN821N v2 [Atheros AR9001U-(2)NG] >>> Wireless router: TP-LINK W8960N (300Mbps Wireless N router) >> >> That's weird, according to TP-Link's website there wasn't any WN821NC >> with a WN821N v2. They "only" let you download the driver for >> WN821N v3. v3 very different from the previous v2 generation, it has >> new chips (AR7015+AR9287?) and needs the ath9k_htc driver. > > WN821NC is actually WN821N shipped with USB cradle. WN821N itself does > not ship with any USB Cradle. The character 'C' in WN821NC mean > "Cradle". If you purchase WN821N, you will not get any USB Cradle. > But, if you purchase WN821NC, what you get is actually WN821N + USB > Cradle. > >> Are you sure, you didn't get ripped off here and someone else >> has "your" v3? > > According to the information printed at the back of my wireless > adapter, it is WN821N v2. > >>> Driver name ar9170usb >>> Linux distro: Ubuntu 10.10 64 bit >>> Kernel version: 2.6.35-24-generic >>> >>> If I use Ndiswrapper + Windows XP driver, I can get full 300Mbps. >> Have you measured that (with iperf/netperf)? Or is it just the >> "Connection Information" pop-up which simply displays "speed: 300 Mbits" ? > > The 300Mbps is just "display". But, when I test my speed on Windows XP > with jperf, it ever reach maximum 2xxMbps. > >>> At the same distance, if I use ar9170usb driver, I can only get >>> maximum 54Mbps speed. >> That's true. here's ar9170usb wiki page: >> <http://wireless.kernel.org/en/users/Drivers/ar9170#features> => working >> "802.11 a/b/g" >> >> Also, the old stack (in 2.6.35) does not have minstrel_ht >> (rate control algorithm for 11n) so ar9170usb is limited to >> the legacy b/g rates. >> >> Furthermore, the old driver lacks any support for aggregation, so the >> uplink throughput (even with the fastest 300 mbits rate and under >> "perfect" lab conditions) would struggle to get to 40 mbit and beyond. >> >> -- >> >> The quickest way around limitations is via backports: >> visit <http://wireless.kernel.org/en/users/Download> >> and get compat-wireless: >> >> <http://wireless.kernel.org/en/users/Download#Getting_compat-wireless_on_Ubuntu> >> >> Then, you can migrate to carl9170 (a new driver with a new firmware) >> for more information, see: >> <http://wireless.kernel.org/en/users/Drivers/carl9170> >> >> However, this "new" driver+fw is still in development. You definitely >> want to keep your compat-wireless package up-to-date. >> >> Best Regards, >> Christian >> > > Will try carl9170 again later. > > Regards, > carl9170 not work. Error when trying to run "sudo modprobe carl9170": "FATAL: Error inserting carl9170 (/lib/modules/2.6.35-22-generic/updates/drivers/net/wireless/ath/carl9170/carl9170.ko): Invalid argument". regards, -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
