LTE - Terminologies & Explanations

LTE - Terminologies & Explanations

PLMN ID is a Public Land Mobile Network Identifier; serves to PLMN unique identification
PLMN ID (not more than 6 digits) = MCC + MNC

MCC is a Mobile Country Code; assigned by ITU; (3 digits)

MNC is a Mobile Network Code; assigned by National Authority; (2 or 3 digits) If the 2 digit MNC is used, then the PLMN will be like ex: 262-09 for 3 didgit MNC, PLMN is like: 262-009

MSIN (MSISDN) is a Mobile Subscriber Identification Number; assigned by operator; (10 digits)

IMSI is an International Mobile Subsciber Identity; serves to uniquely identify a mobile (LTE) subscriber; not more than 15 digits) IMSI will be 14 digits or 15 digits based on the MNC with 2 digits or 3 digits.
IMSI = PLMN ID + MSIN = MCC + MNC + MSIN

ECGI is an E-UTRAN Cell Global Identifier; serves to identify a Cell in global (globally unique); EPC knows the UE location based of ECGI
ECGI (not more than 52 bits) = PLMN ID + ECI

ECI is an E-UTRAN Cell Identifier; serves to identify a cell within PLMN; (28 bits)
ECI = eNB ID + Cell ID

Cell ID is a CELL identifier; serves to uniquely identify a cell within eNB; (8 bits)

eNB ID is an eNodeB Identifier; serves to identify an eNB within PLMN; (20 bits)

Global eNB ID is a Global eNodeB Identifier; serves to identify an eNB in global (Globally unique); (max 44 bits)
Global eNB ID = PLMN ID + eNB ID

Note: The physical Cell ID is different from the Cell ID mentioned above. The Physical Cell ID is used to decode the enodeB signalling by the UE @ phy layer. The Cell ID mentioned above is used by the NAS & RRC layers for EPC management purposes. The most important use of Phy Cell ID is:

Interference to reference signals from reference signals of other cells is eliminated by Physical Cell Identity

Reference: 3GPP 36.508 - Conformance Testing.