Small data transmission (SDT) procedures and failure recovery during an inactive state

A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a base station, the instructions to configure the base station for small data transmission (SDT) in a Fifth Generation New Radio (5G NR) network, and to cause the base station to perform operations comprising:

• detecting a radio link failure during a first SDT of uplink (UL) data from user equipment (UE) in a Radio Resource Control Inactive (RRC_Inactive) state;
• encoding a configuration message for transmission to the UE based on the radio link failure, the configuration message including at least one next-hop chaining count (NCC) parameter;
• decoding a second configuration message from the UE, the second configuration message including an indication of a second SDT;
• encoding a response message for transmission to the UE in response to the second configuration message, the response message including a UL grant;
• and
• decoding the UL data for the second SDT, the UL data encoded using a secure key based on the at least one NCC parameter, and the UL data received based on the UL grant while the UE is in the RRC_Inactive state.

A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of user equipment (UE), the instructions to configure the UE for small data transmission (SDT) in a Fifth Generation New Radio (5G NR) network, and to cause the UE to perform operations comprising:

• detecting while in a Radio Resource Control Inactive (RRC_Inactive) state, a radio link failure during a first SDT of uplink (UL) data to a base station;
• generating a secure key for a second SDT based on the radio link failure;
• encoding a configuration message for transmission to the base station, the configuration message including an indication of the second SDT;
• decoding a response message from the base station, the response message including a UL grant;
• and
• encoding the UL data for the second SDT, the UL data encoded using the secure key, and the second SDT performed using the UL grant while the UE is in the RRC_Inactive state.