Dear Richard,

26 Jul 18 12:26, you wrote to me:

 VS>> My phone and tablet sometimes use IPv6, sometimes they won't, and
 VS>> I find no obvious way to monitor and influence this process.

 RM> My mobile connection is IPv4 only.

Mine too.

 RM> But when I am connected with WiFi at home it will consistently have
 RM> dual stack.

My phone can also be dual stack (it shows both the IPv4 and the IPv6 addresses 
in the network properties, and the IPv6 address is the correct public address 
from my home WiFi network), but http://test-ipv6.com/ in the Chrome browser 
shows that IPv6 is not available. Sometimes it shows that IPv6 is available but 
is not preferred.

Any ideas would be appreciated.

Victor Sudakov, VAS4-RIPE, VAS47-RIPN
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