Saffa,
- Yes. Requirements are not heavy for a lightly loaded Asterisk box.
- Not as far as I know.
- There is lots of information on the net on the subject. Here is one search result…
Connecting Two Asterisk Boxes Together via IAX - There are many soft phone applications around that work for AllStar using VOX as a reverse PTT or with *99/# to emulate PTT. Zoiper is a popular one for AllStar.
Zoiper Setup for AllStar
Also, if you’re a macOS user, checkout Transceive
https://transceive.app