In order to fully understand why smartphones can dial 911 without SIM cards, let’s review some concepts first.

SIM cards identify the cell service subscriber that is trying to connect to the network. Every user has their own SIM, so carriers can direct calls to that specific phone and track usage (and charges) individually. The identifying number of a SIM card is called an ICCID.

Each SIM is internationally identified by its integrated circuit card identifier (ICCID). ICCIDs are stored in the SIM cards and are also engraved or printed on the SIM card body during a process called personalisation.

IMEI is the DNA of a phone; all phones can be identified just with their IMEI.
When there is no sim card, how does a smartphone connect to emergency services?
This is what happens when you put a call through to you friend

Vikky’s phone to cell tower: My IMEI is 123 and my ICCID is 456. Let me call 123–456–7890, please!

Cell tower/mast: IMEI is 123, ICCID is 456; 456 is vikky’s account. I’m from vikky’s company and provide her with service, Vikky has 100 minutes left in account, connecting call.

Vikky:thanks

This is what happens when attempt to call a friend without a SIM card:

Vikky’s phone to nearby cell towers/mast: My IMEI is 123 and I don’t have a SIM card. Let me call 123–456-7890 CONTINUE READING

Hmmmm you are trying to say something.... Kontinu

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