It's not a direct conversion; two different protocols. In other words, they are not compatible. You need a dsl modem, which will have an rj11 connector for the phone line and one or more rj45 (Cat5) connectors for your LAN. They are often a multi-duty box (modem, router, firewall, switch etc.). Normally the ISP provides one (for a fee of course, after all, the are the phone co.). Oh, you will also want filters for each phone.