Ki
Definition
The 128-bit secret authentication key stored on the SIM and in the operator's Authentication Centre (AuC). Never leaves either party in cleartext under normal use.
Related terms
- EPC / 5GC
- Evolved Packet Core (LTE) and 5G Core (5G NR), the all-IP packet cores that replaced the circuit-switched GSM core. 5GC is service-based,...
- ICCID
- Integrated Circuit Card Identifier. The serial number of the physical SIM card itself, stored in EF_ICCID. It identifies the card as a...
- IMEI
- International Mobile Equipment Identity, a 15-digit identifier of the handset hardware. Format is 8-digit TAC + 6-digit serial + 1-digit Luhn check....
- IMSI
- International Mobile Subscriber Identity. A 15-digit number stored in EF_IMSI on the SIM that uniquely identifies the subscriber account on the mobile...
- MSC
- Mobile Switching Centre, the GSM core node that routes calls and SMS between the cellular network and the PSTN, and queries the...
Explained in
- Mobile Technologies: 2G to 5G, GSM/CDMA, SIM and IMEIThe 128-bit secret authentication key stored on the SIM and in the operator's Authentication Centre (AuC). Never leaves either party in cleartext under normal...