t point of view in Release 15 in December 2017, and Abstract Syntax Notation (ASN.1) backward compatibility was established in September 2018. A few important corrections still needed to be incorporated in the December 2018 version, which allows Non-Standalone (NSA) 5G deployment together with LTE. The first full radio and core Stand-Alone (SA) release was completed June 2018 with ASN.1 in December 2018, with the major corrections finalized for the March 2019 version, which allows stand-alone 5G deployment. The first commercial 5G networks were launched in Korea and in the United States in April 2019 based on the Release 15 specifications. 3GPP continued the specification work with the Release 15 late drop for other architecture options in the first half of 2019. The targets for Release 16 completion are December 2019 for the physical layer specifications and March 2020 for radio protocols, with ASN.1 backward compatibility starting in June 2020. The high-level 3GPP schedule is illustrated in Figure 1.8. The focus of the work in Release 15 was clearly on the mobile broadband aspects, with more focus on other use cases in Release 16 and beyond, as can be seen from Chapter 15. The first 5G networks were launched during first half of 2019, and many operators will have commercial 5G running by the end of 2019. There are also a number of 5G devices available in the market. One can get a first estimate for 5G rollouts on the basis of LTE history. We illustrate the timing of LTE and 5G specifications and network launches in Figure 1.8. If we look at just the 3GPP specifications, 5G starts 9.5 years after LTE. One could then simply forecast that 5G rollout and launches will follow the LTE track with a delay of 9.5 years. The first version of LTE specifications was completed in March 2009, the very first network was launched by Telia in December 2009, and a total of more than 40 commercial LTE networks were running by 2011 end, that is, nearly three years after the specification was completed. A major boost for LTE networ