Masquerade (sub network)

Hi I wonder if anybody could help is it possible to create a sub network like Masquerade on a linux box (version SuSE 8) and if so would I have to have two network cards or could it be done with one network card feeding into a hub. At the moment I am using a class C network feeding 20 pc's (with cygwin) but the college want to take the Class C network and leave me with just one ip address. Any help would be greatly appreciated. John Proctor Lecturer at Tresham Institute Kettering Northants England. _________________________________________________________________ Sign-up for a FREE BT Broadband connection today! http://www.msn.co.uk/specials/btbroadband