ffic with the CU. gNB DU I Distributed Unit. Provides radio transmission and reception gNB\DU gNB DU 5GC (5G Core Very low Network) latency links gNB CU gNB DU gNB DU I Centralized Unit. Provides centralized processing and coordination. gNB DU Figure 1.13 - Cloud RAN high-level architecture The optical transmission links that connect the CU to the distributed unit in this approach are very critical. Fundamentally, these links must meet very low-latency requirements and they can be over a kilometer long. But in summary, here, the CU is simply using virtualization technologies to control several distributed units. In this section, we analyzed the concepts of NG-RAN architecture, 5G RAN deployment options, and NR and NG-RAN features, which create the basis for the upcoming chapters, where we will examine them in detail. Summary 5G standardization is being driven to meet the requirements of IMT-2020. We mentioned the three pillars several times: eMBB, URLLC, and mMTC. The theoretical maximum data rate for 5G is 20 Gigabits per second, although the mean data rate for the subscriber is in the low hundreds of megabits per second. RAN latency requirements are around sub-1 ms. 3GPP standardization for 5G started with Release 15 and moved on to Release 16. In Release 17, we also see enhancements taking place. Commercial deployments already started taking place in 2019 and onward into 2020 and 2021. Summary We also analyzed the main components of the 5G system, including the 5G NR and NG-RAN. In terms of the NG-RAN, there are two main elements: the user equipment and the gNB. We saw that tracking areas are designed to make paging more efficient by creating subgroups of gNBs across the Radio Access Network. We discussed the different RAN deployment options available to service providers. At a high level, they are called NSA and SA deployments. We also analyzed the NR and NG-RAN features, which gives us important knowledge for upcoming chapters. First, we talked about dual connectivity. It can be used to significantly increas