perspective and allow an IoT device cost of clearly less than 5 USD. The target is to keep the transaction latency below 10 S. IoT optimization started in Release 12 with a new device category called Category 0 (Cat-0). That category was never implemented in the live networks because major IoT improvements were included in Release 13 with LTE-M and NB-IoT. Release 12 also included Power Saving Mode (PSM) which allows minimization of IoT power consumption with low activity frequency. PSM is utilized in commercial IoT devices. Release 13 included enhanced Discontinuous Reception (eDRX) for power consumption minimization, which practically refers to longer DRX cycles. Another 14 Internet of Things Optimization Table 14.1 loT optimization targets. LTE-advanced optimization Max. path loss 140-145 dB 164 dB Operating time with two Less than 1 yr 10 yr AA batteries Device cost More than 10 USD Less than 5 USD Maximum transaction Typically <2s latency Release 12 Release 13 Release 14 Release 15 Pover Saving Mode Cat-M (eMTC) Enhancements to Wake-up signal (PSM) NB-IoT Cat-M, NB-IoT and Early data Cat-0 UE DECOR DECOR transmission OTDOA Point-to-multi-point Figure 14.2 Main loT optimizations in 3GPP Releases 12-15. improvement in 3GPP specifications was Dedicated Core network (DECOR) in Release 13. It enables dedicated core networks with specific characteristics to be assigned to certain users or devices. All these IoT enhancements turned out to be important for the industry, and therefore, further enhancements were included in Releases 14-15. One important feature in Release 14 is the Observed Time Difference of Arrival (OTDOA) positioning method, since many IoT applications need location information. Another feature is point-to-multipoint transmission, which may be used, for example, to update the firmware of multiple IoT devices simultaneously. Release 15 brought the wake-up signal for minimized power consumption during idle mode paging, and early data transmission for data transmission during the random access procedu