How do I keep my Wifi from dropping out?
Run the following commands, one line at a time in the terminal (CTRL+ALT+T):
echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf
sudo modprobe -rfv iwldvm
sudo modprobe -rfv iwlwifi
sudo modprobe -v iwlwifi
What does this do? The 11n_disable option disables 802.11n features. Adding it to /etc/modprobe.d/iwlwifi.conf makes the change persist after reboots (because it will be part of the module config). The modprobe -rfv commands are removing the kernel modules iwldvm and iwlwifi, and finally the last line modprobe -v is adding iwlwifi back in.
To know what those kernel modules are/do, you can run modinfo <module name> | grep description, which will tell you the following:
iwlwifi is an Intel(R) Wireless WiFi driver for Linux (generic Intel drivers)
iwldvm is Intel(R) Wireless WiFi Link AGN driver for Linux (more specific drivers)
Other suggestions
Now, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, You may have better luck with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. After making these changes, you may need to reboot the router.
Change the wireless setting of IPv6. I tried it with my laptop, which has been continually dropping the connection, and so far, all day long, I have not had a single dropout! It seems to be working. In Ubuntu, in the top right, click on the wireless network icon that shows connectivity. In the dropdown menu, at the bottom, select "edit connections" and then highlight your wireless connection name. Choose edit, then select the IPv6 tab (to the right of the IPv4 tab) and change the setting from "automatic" to "ignore". Save and exit. Reboot your PC. That took care of my problem, and hopefully will yours, too.
Edit the wireless settings, set the IPv6 method to "ignore".
This may be a very simple solution to this problem. My 12.04 wireless connection dropped out every few minutes when connected over Comcast and sometimes also in hotels. This happened consistently on different Comcast wireless setups. On many other wireless setups, it was solid (in my workplace, at Starbucks, for example).
After struggling with many complicated fixes, I finally stumbled across the above solution: No more dropouts.
Edit by cipricus to add images (in KDE Plasma 5.8 interface):
