Communication between IPv6-only to IPv4-only networks
To perform that, we need to have a ipv6<->ipv4 mechanism somewhere. Because the first peer is only able to listen on ipv6 addresses and the second one on ipv4 addresses, something between those peers need to do that job.
And the good news is that TURN is here for that and this behavior is described by RFC6156.
So, for coturn, the config needs two relay-addr entries. One for ipv6, one for ipv4 (cf https://github.com/coturn/coturn/issues/154). This is ok for turn.jami.net, so nothing to do there.
For Jami, this needs to be handled by pjproject but this is not the case for now:
This needs to be able to set "IPV4_AF_TYPE" for PJ_STUN_ATTR_REQ_ADDR_TYPE to be able to allocate an IPv4 candidate for an IPv6 address. However, the rest is not supported because the session will fail. So, the code needs to be done.
Depends on: https://github.com/pjsip/pjproject/issues/2520