Resolve slow connexion when using wifi in ubuntu 11.04, 11.10 Oneiric Ocelot and LinuxMint12

Updated-20/01/2012: If  after installing or upgrading to Ubuntu 11.04 or 11.10 Oneiric Ocelot  you noticed that the connexion is too slow when using the wifi, this is a simple solution. This solution works also for LinuxMint.

1- First Method:  A second solution for this issue can be by using the following :
Open terminal and enter the following command:
.
.

sudo -s
gksu gedit /etc/modprobe.d/ath9k.conf

at the end of the file add this:

options ath9k nohwcrypt=1

Save an restart your OS.
If you still have the issue, then try instructions on step 2.
2- Second Method:
This method involves forcing iwlagn to not use n, the commands will disable n on the device without making it a permanant change, check first if this work for you, if you notice that the speed improved then continue to make the change permanant. If this solution didn`t work for you, then reboot your computer to revert the chnages.

sudo rmmod -f iwlagn
sudo modprobe iwlagn 11n_disable=1

If you notice that the wifi speed improved, then make the change permanent :

gksudo gedit /etc/modprobe.d/iwlagn-disable11n.conf

and add this line to the file:

options iwlagn 11n_disable=1

save & quit
3- Third method : You need to disactivate IPv6, to do that, open terminal and enter the following commands:

echo "#disable ipv6" | sudo tee -a /etc/sysctl.conf echo "net.ipv6.conf.all.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf echo "net.ipv6.conf.default.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf echo "net.ipv6.conf.lo.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf

Then restart your system.