I have two machines both running dual-stack IPv4 and IPv6
I make a SIP call from the softphone on one machine to Jitsi on the
In the SDP offer from the caller, the "c=" line contains "IP6" and an
In the SDP answer from Jitsi, the "c=" line contains "IP4" and an IPv4
Jitsi then starts sending media to the caller using an IPv4-Mapped IPv6
source address [::ffff:192.168.1.128]
The caller could potentially send to Jitsi using one of its IPv4
addresses, but if the caller was a pure-IPv6 host then it wouldn't work.
Why doesn't Jitsi just use IPv6 in the SDP answer?