In this chapter we shall have a look at different identifiers in 5G.
These identifiers will help us to identify the UE and the type of services.
SUPI: Subscription Permanent Identity
It is a globally unique 5G Subscription Permanent Identifier (SUPI) shall be allocated to each subscriber in the 5G system and provisioned in UDM/UDR
SUPI can have IMSI or network-specific identifier.
SUPI is never transmitted
SUPI is protected over radio interface using the Subscription Concealed Identifier.(SUCI).
SUCI: Subscription Concealed Identifier.
It is a privacy preserving identifier containing concealed SUPI
SUCI is a one time use subscription identifier.
Different SUCI is generated after SUCI has been used.
Both UE and Home Network can deliver the SUPI from SUCI and vice versa.
PEI: Permanent Equipment Identity
It is allocated all each 5G UE
PEI represents either IMEI: International Mobile Station Equipment Identity,
IMEISV: IMEI and Software Version Number.
GUTI: Globally Unique Temporary Identifier
5G GUTI is assigned to UE by the AMF as part of registration procedure.
5G GUTI can be re-assigned by AMF anytime.
5G GUTI = GUAMI+5G-TMSI
GUMAI contains : MCC, MNC, AMF Region ID, AMF Set ID, AMF Pointer.
AMF Pointer contains: AMF Region, AMF Set ID.
5G-TMSI : TMSI is a temporary identifier that is unique within a GUAMI
MCC + MNC = PLMN