I got ASUS Wireless-N USB dongle couple months ago, thought it is supported in Linux, however I have no luck to enable it no matter on Ubuntu 12.04 nor 14.04 LTS.

As the box cover claimed Linux supported, someday I put the dongle on my Ubuntu machines then found it has no reaction while plugged in.

I dug into both CD-ROM and Realtek website, well, driver source is quite old, even not able to build in new kernel (3.13+)

Occasionally I found there are lovely maintainers Janez Troha and Stefan Keller, they did great jobs hosting a project maintaining rt8192cu driver, and further more applied DKMS method.

Here is short note to enable the Wifi dongle by Realtek driver for 8192cu / 8188cu devices

Prerequisites

$ sudo apt-get install git build-essential linux-headers-generic dkms

Get driver source

$ git clone https://github.com/dz0ny/rt8192cu.git --depth 1
$ cd rt8192cu

Easy install (DKMS)

$ sudo make dkms

Hard install (traditional, non-DKMS)

$ sudo make install

-enjoy