Is it possible to forward a cell phone via the Internet or sip?

Question

SIP

It is required to forward a cell phone via the Internet in order to be able to talk on it in both directions, receive SMS. That is, a smartphone (gms-gate, or whatever) is in the same place with Internet access, it receives a regular cellular call, and it transmits to another cell phone, which is also connected to the Internet. How can this be organized?
It is required to make it difficult to determine your location for one specific subscriber. The megaphone has a Multiphone, is it normal to somehow use it for these purposes?

Answer 1

Do you need a cell number? Maybe it's easier to take a Moscow number (or another city number) on zadarma and forward it to any other for a penny? True SMS will not.
It is really possible to forward a multiphone to a sip client, but not to a phone. With any other ip forwarding schemes, you will almost always lose the caller's number.