The transition to 5G is happening, and unless you’ve been actively trying to ignore it, you’ve undoubtedly heard the hype. But if you are like 99% of the CS-trained, systems-oriented, cloud-savvy people in the world, the cellular network is largely a mystery. You know it’s an important technology used in the last mile to connect people to the Internet, but you’ve otherwise abstracted it out of your scope-of-concerns.
The important thing to understand about 5G is that it implies much more than a generational upgrade in bandwidth. It involves transformative changes that blur the line between the access network and the cloud. And it will encompass enough value that it has the potential to turn the “Access-as-frontent-to-Internet” perspective on its head. We will just as likely be talking about “Internet-as-backend-to-Access” ten years from now. (Remember, you read it here first.)
The challenge for someone that understands the Internet is penetrating the myriad of acronyms that dominate cellular networking. In fairness, the Internet has its share acronyms, but it also comes with a sufficient set of abstractions to help manage the complexity. It’s hard to say the same for the cellular network, where pulling on one thread seemingly unravels the entire space. It has also been the case that the cellular network had been largely hidden inside proprietary devices, which has made it impossible to figure it out for yourself.
In retrospect, it's strange that we find ourselves in this situation, considering that mobile networks have a 40-year history that parallels the Internet’s. But unlike the Internet, which has evolved around some relatively stable "fixed points," the cellular network has reinvented itself multiple times over, transitioning from from voice-only to data-centric, and from circuit-oriented to IP-based. 5G brings another such transformation, this time heavily influenced the cloud. In the same way 3G defined the transition from voice to broadband, 5G’s promise is mostly about the transition from a single access service (broadband connectivity) to a richer collection of edge services and devices, including support for immersive user interfaces (e.g., AR/VR), mission-critical applications (e.g., public safety, autonomous vehicles), and the Internet-of-Things (IoT). Because these use cases will include everything from home appliances to industrial robots to self-driving cars, 5G won’t just support humans accessing the Internet from their smartphones, but also swarms of autonomous devices working together on their behalf. All of this requires a fundamentally different architecture that will both borrow from and impact the Internet and Cloud.
We have attempted to document this emerging architecture in a book that is accessible to people with a general understanding of the Internet and Cloud. The book (5G Mobile Networks: A Systems Approach) is the result of a mobile networking expert teaching a systems person about 5G as we’ve collaborated on an open source 5G implementation. The material has been used to train other software developers, and we are hopeful it will be useful to anyone that wants a deeper understanding of 5G and the opportunity for innovation it provides. Readers that want hands-on experience can also access the open source software introduced in the book.