TP-LINK TL-WN722NC is a wonderful and cheap USB wifi stick which provides stable connection and has extra USB cradle bundled with it (so you can put it on a window or something). I have to admit there are better solutions than USB sticks, but sometimes you need to solve a problem and this ten bucks piece of hardware can do it for ya.

Unfortunately the driver (ath9k_htc) is still in testing, thus not available in default RHEL6 kernels. In Fedora 16+ it is already there, but how to get it working under RHEL6 (CentOS 6, Scientific Linux 6...)?

Super easy. Just enable ELRepo repository. Don't worry, main repository is safe (does not override any RHEL6 packages):

rpm -Uvh http://elrepo.org/elrepo-release-6-4.el6.elrepo.noarch.rpm

And install the following package. It will take some time to install it, because it's kmod-based package, grab a coffee or something:

yum -y install kmod-compat-wireless

And then you need firmware, download htc_9271.fw file and put it to the /lib/firmware. Now, test it!

modprobe ath9k_htc

You can use your favourite wifi tool to connect to a network. In my case this is, belive me or not, NetworkManager. Works nice. Allright,  we are almost done. I am not sure if the following step is needed, but I just want to be sure proper module will be loaded for wlan0:

echo "alias wlan0 ath9k_htc" > /etc/modprobe.d/wlan0.conf

Reboot, re-test, relax.