Network Security BAN IP?

Hi,


History:-

first of let me tell you how our network works

ADSL router 4 cabled network computers (RJ45 and CAT5e)

and 1 wireless laptop

i was setting up the wireless laptop and realised someone in our area had been accessing out internet FREE on our stupidness!

that problem is solved now, however....





Question:-
how do i stop a CABLED computer connecting to the internet on the network.

for example 10.0.0.3 internal IP, how do i set the ADSL to deny that IP address internet?


im using a CONEXANT ADSL by the way


thanks very much ( sorry to bore you all!!)

Xxx chris XxX

 

If your using dhcp its not a good idea as that ip then could be assigned to any other machines, your looking for mac type filtering to filture by the mac address.

 

yup, MAC how do i block the MAC ?

by he way IP stay the same on our machines not re-newed.

however yes they could change their IP and bypass it!