I have Cox high speed Internet and 2 computers?

Hello there, I could sure use some help . I have Cox high speed internet and 2 desktops , 1 running XP and the Other Vista. I purchased an ASANTE FriendlyNET 10/100 Ethernet Switch. I can only get 1 of the computers to go on the internet, the other will say connected but will not go to the internet. I apologize for I am very new to this computer terminology but I would appreciate anyones help on this matter...Please chime in! Thank you in advance!