Thanks, @senders for the interesting reporting and for the suggestion for a procedure IPv4 mobile data connection not possible - #2 by senders which I attempted to execute, but with 4.4.0.68, not with 4.4.0.64. While it did not work for me on SFOS I managed to make IPv4 work on Android 11 / Xperia 10 III, albeit it did not work out of the box on Android, either, with my operator’s SIM.
The default APN (Access Point Name) settings on Sony’s Android 11 were :
- APN Protocol = IPv6
- APN Roaming Protocol = IPv4
I am not sure has my operator communicated to these values to Sony or to Google, or both but these values are not the same as my operator promotes on their configuration help pages.
Interestingly, the default set of parameters is not editable in Sony Android 11’s Network & internet → Mobile network → Advanced → Access Point Names. There was another ASN profile, for the professional clients of the operators, in which the above settings were:
- APN Protocol = IPv4
- APN Roaming Protocol = IPv4
(For good reason, since in professional usage VPN connection is often requested and the VPNs - that I know - use IPv4. Even a dual protocol IPv4/IPv6 support that SFOS suggests by default, would just create a leak of IPv6 in case the VPN software cannot turn it off.)
In the contrary to the SFOS, Sony Android 11 allows to create a new APN profile in the above menu, and it was possible for me to set a new profile using the values from the help pages of my operators. Not surprisingly, the values on the self-help page are, for APN:
- APN Protocol = IPv4
- APN Roaming Protocol = IPv4
After activating the newly created profile, Sony Android 11 installation started to work as I expected, also with the VPN and with the sites with non-public, fixed IPv4 IP-addresses.
After a couple of reboot and re-testing of this Emma flashed Sony Android 11 62.0.A.3.109 all remains good and I attempted to flash (again, yes, it is tiresome to spend one’s life doing this).SFOS 4.4.0.68.
Of course, it did not work, and even it was still claiming the APN Protocol being “Dual” (i.e. IPv4/IPv6): no change in this parameter changed anything: ip -4 route
remains, desperately empty.
There is no mention about the APN Roaming Protocol in SFOS.
I can understand that Jolla is interested in recovering Google/Android/Sony knowledge about different operator’s settings, bur frankly, the sheer idea of having dependency for this on an underlaying Android installation is on a quite slippery surface what comes to the configuration control:
At least, Jolla should provide a full power APN profile viewer and editor/creator like Sony Android 11 is providing. Now we are shooting in the dark.
You are also right, @senders that probably not enough interest is generated to highlight this issue, since for most people the IPv6-only works and it may go unnoticed for the majority of people that they do not have IPv4 on mobile data, only on WiFi.
But if Jolla is claiming that they are strictly security oriented, they should make IPv4 APN protocol working for all and provide a way to suppress IPv6 altogether.
Unless they can make all the VPN providers to switch to IPv6 tomorrow.