Today, Internet of Things (IoT) communications are a pivotal element of worldwide society and economy. The 3rd Generation Partnership Project (3GPP) standardization framework ensures a global ecosystem around Cellular Internet of Things (CIoT) and provides for proven security mechanisms. Substantial Evolved Universal Terrestrial Radio Access Network/Evolved Packet Core evolution has been achieved in 3GPP to enable the CIoT. In particular, enhanced Machine Type Communication (eMTC) and Narrow Band IoT (NB-IoT) have been designed in Radio Access Network WGs in Release-13 and enhanced in Release-14. eMTC expands the possible applications by using six times the bandwidth of NB-IoT to enable data rates of up 1 Mbps and the integration of voice. 3GPP Relase-17 specified support of NB-IoT and eMTC over Non-Terrestrial Network.