5G Identities full session

5G Identities
Each subscriber in the 5G System is allocated one 5G Subscription Permanent Identifier (SUPI) for use within the 3GPP system. The 5G System supports identification of subscriptions independently of identification of the user equipment. Each UE accessing the 5G System shall be assigned a Permanent Equipment Identifier (PEI).

The 5G System supports allocation of a temporary identifier (5G-GUTI) in order to support user confidentiality protection.

Subscription Permanent Identifier
A globally unique 5G Subscription Permanent Identifier (SUPI) is allocated to each subscriber in the 5G System and provisioned in the UDM/UDR. The SUPI is used only inside 3GPP system

The SUPI may contain:

– an IMSI

– a network-specific identifier, used for private networks as defined in TS 22.261 [2].

– a GLI and an operator identifier of the 5GC operator, used for supporting FN-BRGs

– a GCI and an operator identifier of the 5GC operator, used for supporting FN-CRGs and 5G-CRG

A SUPI containing a network-specific identifier shall take the form of a Network Access Identifier (NAI)

When UE needs to indicate its SUPI to the network (e.g. as part of the Registration procedure), the UE provides the SUPI in concealed form

In order to enable roaming scenarios, the SUPI shall contain the address of the home network (e.g. the MCC and MNC in the case of an IMSI based SUPI).

For interworking with the EPC, the SUPI allocated to the 3GPP UE shall always be based on an IMSI to enable the UE to present an IMSI to the EPC.

Subscription Concealed Identifier
The Subscription Concealed Identifier (SUCI) is a privacy preserving identifier containing the concealed SUPI.

Permanent Equipment Identifier
A Permanent Equipment Identifier (PEI) can assume different formats for different UE types and use cases. The UE shall present the PEI to the network together with an indication of the PEI format being used.

If the UE supports at least one 3GPP access technology (i.e. NG-RAN, E-UTRAN, UTRAN or GERAN), the UE must be allocated a PEI in the IMEI or IMEISV format.

PEI may be one of the following:

– for UEs that support at least one 3GPP access technology, an IMEI or IMEISV

– PEI used in the case of W-5GAN access

– for UEs not supporting any 3GPP access technologies, the IEEE Extended Unique Identifier EUI-64 [113] of the access technology the UE uses to connect to the 5GC.

5G Globally Unique Temporary Identifier
The AMF allocates a 5G Globally Unique Temporary Identifier (5G-GUTI) to the UE that is common to both 3GPP and non-3GPP access. It shall be possible to use the same 5G-GUTI for accessing 3GPP access and non-3GPP access security context within the AMF for the given UE. An AMF may re-assign a new 5G-GUTI to the UE at any time. The AMF provides a new 5G-GUTI to the UE under the specific conditions When the UE is in CM-IDLE, the AMF may delay providing the UE with a new 5G-GUTI until the next NAS transaction.

When the GUAMI identifies only one AMF, the 5G-TMSI identifies the UE uniquely within the AMF. However, when AMF assigns a 5G-GUTI to the UE with a GUAMI value used by more than one AMF, the AMF shall ensure that the 5G-TMSI value used within the assigned 5G-GUTI is not already in use by the other AMF(s) sharing that GUAMI value.

AMF Name
An AMF is identified by an AMF Name. AMF Name is a globally unique FQDN. An AMF can be configured with one or more GUAMIs. At a given time, GUAMI with distinct AMF Pointer value is associated to one AMF name only.

UE Radio Capability ID
The UE Radio Capability ID is is used to uniquely identify a set of UE radio capabilities (i.e. UE Radio Capability information). The UE Radio Capability ID is assigned either by the serving PLMN or by the UE manufacturer