Terminology » 5G Identifiers : SUPI, SUCI, PEI, GUTI, NCGI, DNN, GPSI, NSSAI, NCI

5G Identifiers : SUPI, SUCI, PEI, GUTI, NCGI, DNN, GPSI, NSSAI, NCI

5g 5g identifiers

This page explains different identifiers used in 5G New Radio (NR) and their purposes and structures or formats. It covers SUPI, SUCI, PEI, GUTI, NCGI, DNN, GPSI, NSSAI and NCI.

SUPI

  • Full form : Subscription Permanent Identifier
  • Purpose : Used to identify and authenticate users to the network.
  • Structure : {MCC, MNC, MSIN} ; Size : 15 digits

SUCI

  • Full form : Subscription Concealed Identifier
  • Purpose : Protects user’s permanent Identity from exposure over the air interface
  • Structure : {Home identifier, Routing Indicator, Scheme ID, Home Public ID, Scheme Output}

PEI

  • Full Form : Permanent Equipment Identifier
  • Purpose : Used to identify the device on the network, crucial in scenarios like device blacklisting in case of theft.
  • Structure :
    • 15 digit number
    • Type allocation code (TAC)
    • Serial number

GUTI

  • Full Form : Globally Unique Temporary Identifier
  • Purpose : Used to protect user’s privacy by masking the permanent SUPI
  • Structure : { GUAMI, TMSI} ; Size : 80 bits

NCGI

  • Full Form : NR Cell Global Identity
  • Purpose : Used for identifying the cell that a used is connected to
  • Structure : { MCC, MNC, NCI}
  • NCI is NR Cell identity

DNN

  • Full Form : Data Network Name
  • Purpose : Determines specific data network and services available to the user. Used in 5G core network to route data traffic to external network
  • Structure : String that represents network’s domain name.

GPSI

  • Full Form : Generic Public Subscription Identifier
  • Purpose : Used to route communications to a specific user, without revealing SUPI, facilitates services like voice calls, messaging and push notifications
  • Structure : GPSI can take different forms such as email address, phone number or other public identifiers.

NSSAI

  • Full Form : Network Slice Selection Assistance Information
  • Purpose : Helps in selecting the appropriate network slice for a 5G device.
  • Structure : Slice/Service Type (SST) - 8 bits , Slice differentiator (SD) - 24 bits

NCI

  • Full Form : NR cell identity
  • Purpose : Helps distinguish individual cells within the same network, Used by the network to manage radio resources, Facilitates handovers to ensure smooth communication
  • Structure : 28 bit binary number, Unique cell identities