how do they cut the wifi connection once I move in or out of the train?

Question

Specifically how do they cut the train’s station wifi’s connectivity once I am in the train and the train’s wifi’s network offers me to connect inside the train?

In: Technology

Answer 1

Usually, when the train or even some supermarkets have a layer of metal act like a Faraday cage, keeping any electricity or waves inside/outside.
It works both ways!
That is why you might have issues in supermarkets like lidl/kaufland/carrefour and so on.