Incoming SIP calls to several phones in parallel, which SIP proxy, settings?

Question

Telephony

There is a Gigaset C610A IP on the home network and there is a SIP software client on the cell phone.
The SIP server at the telephony provider is configured so that an incoming call comes only to the last registered phone, the rest are silent.
How to make all phones ring, and you can pick up the phone on any?
There is a home server on Ubuntu Server. Googling, I found out that this needs to be raised by the SIP proxy on the server.
But which one to choose (tried siproxd and Kamailio)? And what exactly is this setting for parallel calls called?

Answer 1

Asterisk will be easier to understand for a beginner.