Network Bandwidth Managing Help

I have 2 computers running off of a LAN, I need to give download priorities to one computer. Rather than limit one computer to a small amount of speed and the other to a high, I understand I can have it so that both computers are capable of running the full 8mb, but priority will be given to computer A and computer B will only be able to run use what computer A isnt using?

How haha, I am running a Orange Livebox instead of a conventional router...
I can't seem to find suitable software either.

Thank you!

 

There is Clark Connect, Smoothwall, and monowall.

 

You can control individual computers by using this software, http://www.netlimiter.com

Or you can centrally control the whole Network by using a Router with Qos.

Example, http://www.newegg.com/Product/Product.aspx?Item=N82E16833181218&Tpk=zyxel+550
.