Overview#International Mobile Subscriber Identity (IMSI) is a unique identifier used Mobile Network Operators (MNO) use to connect Mobile Device calls and communicate with the Mobile Device UICC cards.
The format is:
- The first three digits represent the Mobile Country Code (MCC).
- The next two or three digits represent the Mobile Network Code (MNC).
- Three-digit MNC codes are allowed by E.212 but are mainly used in the United States and Canada.
- The next digits represent the Mobile Subscriber Identification Number (MSIN).
Digits are different from country to country.