Ubuntu 12.10 - Wifi Network was not Deteceted

I was experiencing a problem in configuring a Toshiba laptop for wireless access. It did not identified avaialable wireless networks.

First to check the available PCI devices, I used the below command "lspci". lspci is a utility for displaying information about PCI buses in the system and devices connected to them. By  default,  it  shows  a  brief list of devices.

#lspci

Output for the above command:

....
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
02:00.0 Network controller: Realtek Semiconductor Co., Ltd. Device 8723
03:00.0 Ethernet controller: Atheros Communications Inc. AR8152 v2.0 Fast Ethernet (rev c1)
....

I found a solution suggested on the web http://askubuntu.com/questions/139632/wireless-card-realtek-rtl8723ae-bt-is-not-recognized

In the above list, I found that the available wifi card is from Realtek. Realtek is making the official Linux driver available unofficially (via Dropbox). For unknown reasons, neither the Windows nor Linux drivers are available on their website (yet). But Realtek tech support has been providing a Dropbox link with the source code/firmware tarball which numerous users have reported as working.

Where do I get it? Is it safe? The driver can be downloaded via this Dropbox link. The downloaded file has the following MD5 or SHA1 hashes: (which you can verify with md5sum or sha1sum).

    MD5: fd10e9a347c6447f649324d6bdab53de
    SHA1: 1ccd6ae73878d8bf65bd7c0384e333b121606230

To install the above driver, I followed the below steps.

Open a terminal with Ctrl+Alt+T.
Since I haven't installed "build-essential", I had to first install them using the below command.

#sudo apt-get install build-essential linux-headers-generic linux-headers-`uname -r`

Pasted the below line to download and extract the driver archive in one single step:

#wget -O- http://dl.dropbox.com/u/57056576/DRIVERS/REALTEK/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012.tar.gz | tar -xz

Note: You can directly download this from the website using http://dl.dropbox.com/u/57056576/DRIVERS/REALTEK /rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012.tar.gz. Then you need to extract it to a folder.

Then I changed to the extracted driver's directory.

#cd rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012

To instal the driver, I used the below command.

#make

But I was getting the below error.

make -C /lib/modules/3.4.6-2.10-default/build M=/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012 modules
make[1]: Entering directory `/usr/src/linux-3.4.6-2.10-obj/i386/default'
CC [M] /home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012/base.o
/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012/base.c: In function ‘_rtl_init_mac80211’:
/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012/base.c:320:6: error: ‘IEEE80211_HW_BEACON_FILTER’ undeclared (first use in this function)
/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012/base.c:320:6: note: each undeclared identifier is reported only once for each function it appears in
make[4]: *** [/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012/base.o] Error 1
make[3]: *** [_module_/home/leraly/rtl_92ce_92se_92de_8723ae_linux_mac80211_0006.0514.2012] Error 2
make[2]: *** [sub-make] Error 2
make[1]: *** [all] Error 2
make[1]: Leaving directory `/usr/src/linux-3.4.6-2.10-obj/i386/default'
make: *** [all] Error 2
To resolve the above error I followed the below steps. [Sorry I couldn't find some other way to solve the above error. Then I tried the below method]

Open the "base.c" file using my favourite text editor. Then I commented the line that contains "IEEE80211_HW_BEACON_FILTER". Then I saved the file and exit.

Again I followed the below steps.

#make
#sudo make install.

I was able to successfully installed the above driver.

To test the driver by loading it (this is a one-time step; after you reboot once, the driver should automatically load on every boot) I entered the below command:

#sudo modprobe rtl8723e

After rebooting the laptop, it was able to identified available wireless networks.

I can't gurantee that the above method will solve your problems but it worked for me... :)