Afterword: Beyond 5G

The ink is barely dry on the 5G specifications and its adoption still nascent, yet industry insiders are already abuzz with the possibilities 6G will bring. The transition from 4G LTE to 5G is not a one-time flip-of-a-switch transformation but rather a journey composed of gradual enhancements and upgrades to cellular capabilities, new service offerings, and a shift toward cloud-native architectures. This gradual transition is in line with all the previous cellular generational transitions and will continue to be the model for the future. Similar to how IMT-2020 specifications, defined in 2015, became the foundational standard for 5G, IMT-2030, expected around the year 2025, would lay the foundation for services that will define the next era of cellular services—6G.

Mobile operators and service providers have steadily been putting the newly acquired RF spectrum into service, while deploying vRAN architectures, xHaul transport, and cloud-native 5G Core. At the same time, members of academia, industry groups, government-led institutions, and equipment vendors are hard at work advancing the cellular technology further. Some of the preliminary concepts at the forefront of 6G development are the accelerated use of artificial intelligence (AI), machine learning (ML), the possibility of a new human–machine interface, and, of course, additional bandwidth through higher-frequency RF spectrum.

Increased bandwidth usage has been a consistently common factor across all mobile generations, and the trend is expected to continue, even accelerate, in 6G with the continued adoption of bandwidth-intensive applications. 5G unlocked new sub-7GHz and mmWave spectrum in the 24–52GHz range, and research is ongoing to unlock an even higher spectrum in the 100GHz–10THz range, generally referred to as terahertz (THz) frequencies. The challenge associated with THz frequencies is their signal propagation properties—similar to the mmWave spectrum. Not only is it more difficult for THz frequency waves to penetrate buildings and structures, they are also more easily impacted by the slightest weather anomalies. Research is ongoing to gauge the commercial viability of THz frequency ranges for cellular use as well as new and innovative antenna designs to overcome some of the obstacles associated with such a high frequency range spectrum.

However, higher speeds and bandwidth availability are usually a means to an end—in this case to support new service offerings. What these new services are going to be in 6G are anyone’s guess at this point in time, but industry experts agree that 6G will further blur the lines between the human, physical, digital, and virtual worlds. Previous cellular generations had been underscored by multimedia and, to some extent, immersive content, but future cellular generations will be defined by the fusion of these different “worlds” and the extrasensory experiences resulting from this fusion. Sure enough, the augmented reality (AR), virtual reality (VR), and mixed reality (MR) applications (collectively called XR) will continue to grow and thrive, but experts also theorize the use of a new human–machine interface, where humans interact with their environment and other users through sensory and haptic messaging. Whether this new human–machine interface will be in the form of wearable tech, smart body implants, embedded devices in one’s environment, a combination of all these, or something entirely different is yet to be seen. It is, however, abundantly evident that such an interface will use massive amounts of data and require ultra-low response time, while maintaining mobility, signifying the continued importance of Multi-access Edge Compute (MEC).

This new framework of multiple infused worlds, referred by some as the metaverse, will create digital societies for people to interact in this new environment. The concept of the metaverse, however, has far reaching real-life applications beyond just leisure and entertainment. It provides an environment free from spatial or temporal constraints that can be used to simulate and monitor physical world activities in a virtual world. Coupled with advancement in AI, ML, and automation, this metaverse can be used to analyze, predict, and solve problems before they manifest in the physical world. Next-generation industrial operations are expected to go beyond simple automation and use these new capabilities in a wireless environment, potentially powered by private 6G to create safe and effective environments that usher in a new era of productivity.

If history is any indication, 6G will fulfill a lot of the promises of 5G and will make some of its own. The research and standardization work for 6G is still in the early stages, but both industry players as well as governments around the globe are looking to influence the standardization effort with ideas of their own. 5G (and 4G before that) have definitively proven the ever-growing importance of mobile telecommunication, and the technology leaders of 6G will undoubtedly hold the proverbial keys to the kingdom in an ever-changing geo-political landscape.

So what does this mean for the network architects? 5G will dominate the mobile landscape the next few years. 6G is still in its infancy and will need years to become a subject of broad interest. For a network architect, however, the trajectory has already been set for supporting the subsequent mobile generations. Besides the introduction of new networking protocols as well as the design challenges associated with vRAN and mobile core decomposition, network architects must acquire additional skill sets to design cellular networks over both private and public cloud environments. The increased scale of deployment as well as time-to-market pressures will also demand expert knowledge of automation and deployment tools such as Kubernetes and Ansible. In short, the network architects of the future will be required to bring the cutting-edge network technologies into the very fabric of cloud environments. These are the skills this book has focused on and will be necessary for any network architect over the next decade.