5G QCI in the QoS of the 5G Network

5G QCI "Quality of Service Class Identifier", is a numerical identifier that corresponds to a specific set of QoS parameters such as,

  • Resource Type: Indicates whether the traffic is guaranteed bit rate (GBR) or non-GBR.
  • Priority Level: A value between 1 and 256, with lower values indicating higher priority.
  • Packet Delay Budget (PDB): The maximum acceptable delay for the data packet transmission.
  • Packet Error Rate (PER): The maximum acceptable rate of erroneous data packets.
  • Averaging Window: The time period over which the PER is calculated.

Accordingly, each 5G QCI has certain use cases such as,

  • QCI 1: Supports real-time, interactive, and conversational services like VoIP.
  • QCI 5: Supports IMS signaling.
  • QCI 9: Supports best-effort data services.