Slow connection to my particular brand of router over WiFi with Lion on MacBook Pro I own a MacBook Pro for some months now, it came with OS X Lion pre-installed. Since then, surfing the net with it is painful due to slowness. I also have a MacBook with Snow Leopard on it, there the internet works at normal speed. Based on this I conclude the problem is inside the MacBook Pro - it shows full WLAN connectivity but loading Google takes forever. My Router is a AVM Fritz!Box.

What I tried so far to optimize the speed - unless (noted) the changes made below don't affect the measured latency or speed at which pages render:


Resetting the router, turning WLAN on and off
Switching WLAN channels, trying 802.11n+a and 802.11n+g 
Deleting all Wi-Fi networks in the system preferences
Resetting PRAM and NVRAM
Re-starting the MacBook Pro multiple times in a row
Disable iCloud in system preferences
Using another Browser than Safari
Renaming the network
Disableing "Use channels optimized for 300 Mbit/s" in my router (this helped, but still not to equal the speed of Snow Leopard)


What else could I try? I read changing the DNS server Google's can help, bit to  my understanding, this really can't fix the problem. Reinstalling is not an option. I am really desperate to solve this problem because it is more than annoying!
Have you tried flushing the DNS cache? In Terminal.app, enter dscacheutil -flushcache.



It could be your DHCP router handing out IPv6 information incorrectly, which is especially annoying if you don’t need IPv6 — like at home. This seems like the most logical explanation, given that all browsers and applications are suffering from the speed issues.

Go to System Preferences → Network → WiFi → Advanced → TCP/IP and set “Configure IPv6” to “Link-local only”.