The popular standard protection service providers offer is the Personal Identification Number (PIN). This four-digit code prevents unauthorized access to the SIM card, ensuring data security.

A PUK code is required if a GSM SIM card was locked after entering the wrong PIN code three times in a row. Entering a wrong PUK code ten times in a row disables the SIM card permanently.

This is a numeric code which must be entered each ... In GSM mobile phones, the PIN is normally associated with the SIM card (not the phone) and must be entered each time the phone is switched ...