We can use another mac address of an another computer and we can use their internet speed.
It is easy to get their mac address over the lan.
It only works if there are computers over your lan.
Lets go to the process....
Just download a software by googling over the internet.
OR
Download it from here.
http://www.youngzsoft.net/cc-get-mac-address/
after downloading the software install it and open it.
It looks like this
Now this software scans all ip address on the lan and it also scans the mac address of the ip addresses.
Then copy the mac address of the ip and save it in a note pad.
Now open start--> Control Panel--> Network And Sharing Center-->View Status.
A pop up appears
Now click on properties.
Another pop up appears then click on Configure Tab.
After clickin on configure a new pop up appears.
Then click on advanced and in advanced you will find network address.
Now paste the mac address value in the Value Tab and press OK Tab.
Now your settings will reconfigure and you will spoof mac address of another computer.
