How does a web session remain consistent when changing connection?

Question

When browsing on a mobile device, it is possible to change multiple times between a 3G and WiFi connection, with associated IP address change.

How does a website maintain a user's session when their connection changes, as it would appear to be a new connection to the server?

Answer 1

The user session is based on a random code.

The code is send by the browser to the website as an identifier.

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