Howto: Tweak and maximize your bandwidth in Linux via sysctl!

Here I will unleash a few hidden settings that should improve your internet speed, and work with all current linux operating systems including Ubuntu:

1. Open a Terminal via Applications->Accessories->Terminal

Type:

    sudo vim /etc/sysctl.conf    (press i for edit mode)

Then Paste the Following at the end of the file:

 ## increase TCP max buffer size setable using setsockopt()
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
 ## increase Linux autotuning TCP buffer limits
 ## min, default, and max number of bytes to use
 ## set max to at least 4MB, or higher if you use very high BDP paths
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
 ## don't cache ssthresh from previous connection
net.ipv4.tcp_no_metrics_save = 1
net.ipv4.tcp_moderate_rcvbuf = 1
 ## recommended to increase this for 1000 BT or higher
net.core.netdev_max_backlog = 2500
 ## for 10 GigE, use this, uncomment below
 ## net.core.netdev_max_backlog = 30000
 ## Turn off timestamps if you're on a gigabit or very busy network
 ## Having it off is one less thing the IP stack needs to work on
 ## net.ipv4.tcp_timestamps = 0
 ## disable tcp selective acknowledgements.
net.ipv4.tcp_sack = 0
 ##enable window scaling
net.ipv4.tcp_window_scaling = 1

Type :wq to exit and save.

Type in terminal

    sudo sysctl -p

to apply the settings.
You can disable all these settings by removing these lines you added via:

    sudo gedit /etc/sysctl.conf