# 6G Use Cases and Scenarios: A Comparison Analysis Between ITU and Other Initiatives
## 11 The 6G Enabling Technology Categories  
This section summarizes the 6G enabling potential technologies mentioned in the scientific literature are summarized. In [29], the optimal use of wireless resources is underlined. In this sense, technologies at the physical layer, such as massive MIMO and mmWave technologies, can be considered for Tera Hertz (THz) frequencies above 300 GHz. Some use cases are presented. Smart city is one of them characterized by the Internet of Things (IoT), Cloud Computing, Fog and Edge Computing, etc. AI and ML are innovative features that will be included in the 6G networks. The paper also hypothesizes potential use cases, like education, digital agriculture, and seamless coverage anywhere using AR/VR, and future mobility. After an overview of the 6G vision, together with technical requirements and scenarios, ref. [30] lists some potential 6G-enabling technologies, such as ultra-massive MIMO and THz communications, advanced spectrum management, and new waveforms and modulation. In addition to AI and ML, the paper analyzes Reconfigurable Intelligent Surfaces (RISs), holographic radio, blockchain platforms, and Integrated Sensing And Communication (ISAC). Ref. [31] introduces the concept of Coherence Transition, which is the integration of holographic radio and photonics. According to the authors, these technologies at the PHY layer will be crucial components in the 6G network design and planning. Ref. [32] describes the main 6G-enabling technologies as THz communications, Reconfigurable Intelligent Surfaces (RISs), AI/ML, ultra-massive MIMO, and distributed intelligent computing networks. They have a strong impact on the most important features of the next 6G wireless networks, such as data rate, efficiency in terms of spectrum and energy efficiency, coverage, and reliability. Ref. [33] describes potential technological enablers and possible 6G use cases. The mentioned technological enablers are as follows. * THz communications and optics;
* Full duplex and Sensing and localization;
* Multi-connectivity, virtualization, and low-power functionalities;
* Knowledge sharing and user-centric network architecture in terms of network intelligence. In addition to AI and ML, ref. [34] introduces technologies such as VR, AR, XR, IoT, and blockchain platforms. Ref. [35] hypothesizes that 6G will be human-centered. Security and privacy are the most important requirements from the end user's perspective. Moreover, applications with a high level of immersive degree are mentioned and described, such as Digital Twins, extended reality (XR) and Virtual Reality (VR). Other technologies at the network level are also analyzed, such as Cloud/Fog/Edge Computing, and heterogeneous networks. Finally, ultra-massive MIMO and optics are mentioned as advanced transmission schemes. According to [36], the most important features of the 6G system will be immersive reality, intelligent manufacturing, smart infrastructure, XR immersive communication, and Digital Twins. The list of the main technologies, applications, and services we have considered to characterize the 6G use case and the vertical market sectors is given in Table 10 with the corresponding acronyms. As shown in Table 10, the considered technological features have been grouped into the following six main categories:  
* **Communication Technology**. This refers to the transmission technologies supporting specific use case applications. They can be broadband or narrowband (e.g., IoT). Moreover, they are also able to provide very low latency and extended coverage features. * **Localization Technology**. This refers to both localization features and localization technologies, including the Global Navigation Satellite System (GNSS) or other technologies;
* **HCI Technologies**. This considers human-computer interface (HCI) communications, including VR, AR, MR, holography, and virtual personal assistants. Touchscreen and keyboard devices are also considered for the device remote control;
* **Data Acquisition**.