A:AnswerIt is both. There is a switch to select the type of line service available. The switch is for TT (touch tone) or DP (Dial Pulse). I think Dial Pulse is for a line that accepts rotary dialing only, if such a thing still exists. I have an old rotary phone and it works on a modern line.
A:AnswerNot sure what you mean by "old wiring" and "new wiring". Your best bet is to ditch the obsolete analog system and to to VoIP (voice over internet protocol). Log into Google Voice and get a free telephone number. Then get the OBI interface device for Google Voice. Connect the device to your spare router port and plug your phone into the phone jack on the device. Now your calls will go over the internet rather than the antiquated copper wire system.