Re: [Linphone-users] Report the bug

[Stuart D. Gathman]

On Wed, 10 Apr 2019, 杨智 wrote:

> I download your app from play store. I install Linphone App in two devices.
> If these two devices connect to the same wifi network. Make the call, both
> side cannot heard each other. Once one device used the different network
> such as another wifi network or 4g. It will work correctly. 
>
> Could you give me the explanation?

Short answer: NAT

Long answer:

There is a world wide conspiracy to avoid IP6 so as to keep customers in
IP4 NAT jail.  Complex firewalls can code multiple SIP users in
alternate ports - but there is no standard for doing so.  NAT is Evil™.

Solution: get on IP6.  With a stable IP6, you can do peer to peer calls
as well.  (Although some library used by linphone-3.6.1 seems to have broken
peer-to-peer in the last 2 months on the Fedora distro.)

A VPN can provide a stable IP6 for a mobile device.  A Mesh VPN (like
Cjdns) can do so efficiently (without relaying through home base).

--
              Stuart D. Gathman <address@hidden>
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.