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Signals for transitioning to a radio resource control (RRC) connected state and maintaining the RRC connected state could cause overheads (e.g., power consumption and delay) to a wireless device having a small amount of data to transmit when in an RRC idle state or an RRC inactive state.

The 3rd Generation Partnership Project (3GPP) has introduced technologies to reduce the overheads. This article gives a brief introduction of the technologies and investigates protocol aspects of the technologies.

What’s inside:

This article is organized as follows: Section 2 describes cellular internet of things (CIoT) optimization which supports early data transmission after transitioning to an RRC connected state. Section 3 describes SDT technologies which support data transmission without transitioning to an RRC connected state. Section 4 provides a summary.

In this whitepaper, you’ll learn more about:

  • CIoT optimization
  • Overall procedure from generation of UL data in RRC idle state to transitioning back to RRC idle state
  • CIoT optimization procedure for transmission of UL data being generated in RRC idle state
  • Small Data Transmission (SDT)
  • SDT technologies for 4G LTE
  • Comparison of SDT for 5G NR and UP SDT for 4G LTE
  • SDT technologies for 5G NR: subsequent transmission
  • SDT technologies for 5G NR: non-anchor relocation
download the whitepaper