How is it that by just putting a SIM card into your phone you have access to 4G/5G?
In: Technology
The “SIM” in “SIM card” stands for “Subscriber Identity Module”. It is basically a way of storing an “IMSI” or “international mobile subscriber identity” number and encryption key that uniquely identifies the device, associating it with a user that has been authorized to access the cellular network. There are cell towers all around that the phone can talk to, but only if the user has paid for access (or it is an emergency call).
Just having a SIM card isn’t sufficient, you need that SIM card to be associated with an active account to be provided the service. Once your cell phone can communicate with the cell towers it can pass information in the form of phone calls or it can communicate data for things like web pages.
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