On 31/07/2019 08:16, Andy Burns wrote:
The Natural Philosopher wrote:

WiFi Calling will activate on phines that support it and mobile
networks that support it when
(a) there is an adequate wifi signal
(b) the mobile signal strength drops below a given level.

(c) When the SIM provisioning allows it

I did say "on phones that support it and mobile
networks that support it when "

previously my phone was on Tesco (O2 mvno) and I couldn't even enable
wifi calling, now it's on Virgin (EE mvno) and I can enable it, but it
still won't work as virgin don't support it.

When the signal drops the phone will open UDP connections to ports 500
and 4500

Also IP protocol 50 (ESP, neither TCP or UDP) those are the same three
connections that femtocells use to create IPSEC tunnels back to the
provider.

It would be strange if they used different...


--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.