Part 1. 5G and Beyond Mobile Landscape -- Chapter 1. Drive towards 6G -- Part 2. UDNs for B5G -- Chapter 2. Cell-Free MIMO Systems for UDNs -- Chapter 3. Radio Resource Management and Access Polices for B5G -- Chapter 4. Energy Efficient RF for UDNs -- Chapter 5. Security for UDNs: A Step Towards 6G -- Chapter 6. Channel Estimation in RIS-Aided Networks -- Part 3. PON technology for UDNs -- Chapter 7. Integrated Optical-Wireless Interface and Detection -- Chapter 8. Modulation and Equalization Techniques for mmWave ARoF -- Chapter 9. Optical-Wireless System Performance, Deployment and Optimization -- Part 4. Cloud based UDNs for beyond 5G -- Chapter 10. Virtual Networking for Lowering Cost of Ownership -- Chapter 11. Advanced Cloud Based Network Management for 5G C-RAN -- Chapter 12. Resource Management for Cost-Effective Cloud Services -- Chapter 13. Demonstrating Cloud-Based Services for UDNs: Content Distribution Case Study -- Chapter 14. SDN-Based Resource Management for Optical-Wireless Fronthaul -- Chapter 15. Cloud Based Content Management for B5G.

This book tackles the 6G odyssey, providing a concerted technology roadmap towards the 6G vision focused on the interoperability between the wireless and optical domain, including the benefits that are introduced through virtualization and software defined radio. The authors aim to be at the forefront of beyond 5G technologies by reflecting the integrated works of several major European collaborative projects (H2020-ETN-SECRET, 5GSTEPFWD, and SPOTLIGHT). The book is structured so as to provide insights towards the 6G horizon, reporting on the most recent developments on the international 6G research effort. The authors address a variety of telecom stakeholders, which includes practicing engineers on the field developing commercial solutions for 5G and beyond products; postgraduate researchers that require a basis on which to build their research by highlighting the current challenges on radio, optical and cloud-based networking for ultra-dense networks, including novel approaches; and project managers that could use the principles and applications for shaping new research proposals on this highly dynamic field. Provides a concerted technology roadmap towards the 6G vision focused on the interoperability between the wireless and optical domain; Discusses the benefits of 6G, introduced through virtualization and software defined radio; Includes concepts as well as applications to provide a base for the reader to acquire new knowledge on optical, wireless, and cloud computing.