I-RNTI

Technical Explanation

When suspended to RRC_INACTIVE, the UE receives an I-RNTI. It exists in two formats: Full I-RNTI (40 bits, containing 24-bit gNodeB ID and 16-bit UE context ID) and Short I-RNTI (24 bits). When resuming, the UE presents its I-RNTI, enabling the receiving gNodeB to retrieve the stored context over the Xn interface.

Key Functions

• Uniquely identifies suspended UE context across the RAN notification area
• Contains gNodeB routing identity and local context reference index
• Available in 40-bit Full I-RNTI and 24-bit Short I-RNTI formats