I don't have the details in mind but checkout https://en.m.wikipedia.org/wiki/Handoff#Implementations https://en.m.wikipedia.org/wiki/Handoff#Implementations S

I don't have the details in mind but checkout https://en.m.wikipedia.org/wiki/Handoff#Implementations https://en.m.wikipedia.org/wiki/Handoff#Implementations Since digital, handsets validate the tower they are talking too, this info is stored on sim or device depending on model. So to intercept 2g, there is some work See https://youtu.be/DU8hg4FTm0g https://youtu.be/DU8hg4FTm0g