layer 2 switch network config

Im having internet connection from a Isp and they had my NIc(Network Interface card) Macaddress noted.I think they uses Mac filtering while providing singple pc internet connection.but I have few more PC’s and I wana share my Internet with those 3 computers. can anybosy plz tell me the secure way that I can share my internet without knowing my Isp……anybody with correct ans would be appriacited…………