What is a SIM card?
A SIM card, or Subscriber Identity Module, is a small plastic card with an integrated circuit that is required by mobile network operators to identify a user device. The identity is used by the network operators for billing purposes and to enable connectivity between the device and communication services such as mobile telephone networks and the internet. SIM cards use an ICCID (Integrated Circuit Card Identifier) and an IMSI (International Mobile Subscriber Identity) as part of the connection and identification process.
What information is stored on a SIM card?
- The international telephone number or IMSI
- The SIM number or ICCID
- The country of origin
- Authentication key
- The network operator who originally activated the SIM
- Location area identity
- Memory capacity for contact lists and SMS messages