Minimization of padding and resource wastage in message 3 (msg3) for early data transmission (edt)

An apparatus of a base station, the apparatus comprising:

• processing circuitry, wherein to configure a User Equipment (UE) for early data transmission (EDT), the processing circuitry is to:
• decode a physical random access channel (PRACH) preamble from the UE, the PRACH preamble received as a PRACH procedure Message 1 (MSG1), and the PRACH preamble including a request for the EDT;
• encode a random-access response (RAR) message for transmission to the UE as a PRACH procedure Message 2 (MSG2), the MSG2 including an uplink (UL) grant for the EDT with a transmission block size (TBS) indicator;
• and
• decode UL data for the EDT, the UL data received from the UE as a PRACH procedure Message 3 (MSG3) based on the UL grant and a TBS selected from a plurality of available TBSs based on the TBS indicator;
• and
• memory coupled to the processing circuitry, the memory configured to store the TBS indicator.

A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the instructions to configure the one or more processors to cause the UE to:

• encode a physical random access channel (PRACH) preamble for transmission to a base station as a PRACH procedure Message 1 (MSG1), the PRACH preamble including a request for early data transmission (EDT);
• decode a random-access response (RAR) message, the RAR message received from the base station as a PRACH procedure Message 2 (MSG2) and including an uplink (UL) grant for the EDT with a transmission block size (TBS) indicator;
• select a TBS from a plurality of available TBSs corresponding to the TBS indicator;
• and
• encode UL data for the EDT to the base station as a PRACH procedure Message 3 (MSG3) using the UL grant and the selected TBS.