How to give access to a home phone from a remote location?

Question

Asterisk

Nubian question, far from the topic, googling did not help.

• There is an apartment A with a city telephone and the Internet.
  
• And there is apartment B , where there is only the Internet.
  

I would like to be able to fully use the city telephone line in sq. A from sq. B.
So that sq. B is just like the next room, where the Dect radio tube is finishing off. (From A to B does not finish, alas).
There is a Cisco / LinkSys SPA-3102 voice gateway and zero experience in organizing Internet telephony.
I don't really understand yet:

1. Do I need to raise the Asterisk server or can I get by with one box of 3102?
   
2. If necessary, will a Linux network drive pull it (the torrent client works there normally), or do you need stronger hardware?
   
3. Will I have to connect to an external service like the same SipNet, or can everything work autonomously?
   
4. Which phone to buy. device in sq. B? As I understand it, you need a VoIP phone, for example Yealink W52P
   
5. Poke, please, in the tutorial (possible in English) where exactly my task is chewed, if there is one at hand.
   

Answer 1

1. Asterisk is not required, you can get by with a gateway box.
2. Do you mean NAS? In terms of hardware performance, it could have pulled (I don’t claim that they are different, and the hardware is different), but a more interesting question is how much time and effort it takes to install Asterisk on that Linux. There Linux can be specific and stripped down, hemorrhoids are quite likely.
3. No. SipNet (etc.) is mainly needed in order not to use a landline (or cell) phone.
4. First, try setting up through some softphone. This is a class of client programs for VoIP, such as Skype. Only Skype has its own protocol, and you need any softphone that supports the SIP protocol. Thousands of themA dozen such programs can be easily googled (but some of them are crooked, yes). If everything can be set up, then it will be possible to buy Yealink for convenience. And if it doesn’t work out, then at least don’t throw money away.
5. Look in the settings of your box for the word hotline (hot line). Or google "phone forwarding". I will not give a ready link.
6. You will also need to configure the router (forwarding SIP and RTSP ports; it is possible to configure DDNS if the address from the provider is dynamic; it is possible to STUN on the VoIP gateway).
Upd. just in case, I'll add about the hotline. This is such a mode of operation of the gateway, when when a signal arrives at the port (an incoming call or picking up the handset on the phone), another port is automatically opened or even some number is automatically dialed. A kind of analogue of "lady, give Smolny." Establishing a connection without manual dialing.