====== Diagnose WiFi ======
http://www.cyberciti.biz/tips/linux-find-out-wireless-network-speed-signal-strength.html

===== Broadcom has problem with 11n =====
Fedora 21 (kernel-3.19.3) comes with kernel mod brcmsmac, the opensource driver from broadcom.

    Problem wifi slow and lost connection
    
Wait till next update.

    sudo su
    modprobe iiwlwifi 11n_disable=1
    echo "options iwlwifi 11n_disable=1" > /etc/modprobe.d/iwlwifi.conf
    
http://www.cyberciti.biz/faq/fedora-linux-install-broadcom-wl-sta-wireless-driver-for-bcm43228/