MS Identity Number IMSI, MSISDN, TMSI and IMEI
- IMSI : the user number is unique in the world (stored in HLR and SIM card)
MCC=Mobile Country Code (3 digits, for example 466 for Taiwan).
MNC=Mobile Network Code (2 digits, for example 92 for Taiwan LDTA, 90 for
MSIN=Mobile Station Identification Number.
NOTE: IMSI is 15 digits at most (E.212 format).
- MSISDN : the phone number of MS
NDC=National Destination Code.
NOTE: IMSI is E.164 format, international roaming use E.214 format(MCC+
- TMSI : the number is used for protecting IMSI to avoid send the IMSI on the radio path
The length of TMSI is less than that of IMSI. So, we can page the more users in
the same control channel.
The number is defined by system operator.
- IMEI : the equipment number is unique in the world (can be identified by EIR)
TAC=Type Approval Code(6 digits).
FAC=Final Assembly Code(2 digits).
SRN=Serial Number(6 digits).
sp=spare(1 digits): for future use.
(phase 2 will incorporate a software version number code SV)