June 20th was recently celebrated as World Wi-Fi Day, a global initiative to help bridge the digital divide and to celebrate the legendary role Wi-Fi has played in “connecting the unconnected.” From humble beginnings as a privileged consumer network and a “Guest” network in enterprises, Wi-Fi has become so pervasive that today, businesses and consumers depend on it for nearly everything.
Still, the exponential growth of wireless traffic and mobile data is outpacing Wi-Fi infrastructure’s capability, coverage, and capacity across venues around the world. Wi-Fi continues to evolve, but the recent COVID-19 pandemic demonstrated that most businesses and their wireless use cases continue to expand outside buildings, which has traditionally been the forte of macro cellular networks. For example, the acceleration of distance learning around the world has forced administrators and educators to consider new private wireless broadband technologies with larger coverage and stronger reliability but more affordable than macro cellular networks.
Similarly, the ongoing flood of new wireless IoT devices in all operational technologies (OT) verticals is forcing enterprises to evolve their wireless networks to combine the flexibility and affordability of Wi-Fi with the performance, security, and deterministic nature of cellular networks for critical applications. New mission-critical applications, such as video surveillance, robotics, IoT, and warehouse automation can simply no longer tolerate anything less than robust wireless connectivity and predictable performance that isn’t subject to the wireless interference, media contention, and roaming issues that have historically hindered the use of wireless within the enterprise. Just as Ethernet needed an extended network, so too does Wi-Fi.
Enter CBRS, a wireless standard launched in the United States in 2019, that allows enterprises to operate their own Private Cellular Networks (PCNs) and cater to an emerging set of wider area wireless use cases across various enterprise verticals. CBRS utilizes 150 MHz of spectrum in the 3.5 GHz band, half of which is unlicensed, similar to Wi-Fi. Companies can request to use a certain number of channels for a specified amount of time and in a certain area through a ‘spectrum sharing’ database administered by select Spectrum Access Systems (SAS) services. CBRS realizes the vision of spectrum sharing, changing the way government-held spectrum has been used since the mid-1990s. Best suited to neighborhood outdoor deployments and in-building installations, CBRS extends the coverage area offered by Wi-Fi by up to ten times outdoors and up to four times indoors.
Combine this with the ongoing once-a-decade evolution of cellular technology from 4G LTE to 5G which enables a “wired-like wireless” experience through support for ultra-reliable, low-latency, and secure wireless links, and allows for higher data rates as well as a massive number of IoT connections, and we can visualize how next-generation enterprise wireless networks will soon be built.
The use cases
First, for non-carpeted industries such as logistics, manufacturing, and smart cities, which have historically struggled with indoor and outdoor Wi-Fi, enterprise PCNs offer a compelling alternative. From latency-sensitive remote control and video applications that require outdoor wireless backhaul, to automation on factory floors and predictable performance of critical care apps in RF-challenged hospital deployments, the advantages of enterprise PCNs are demonstrable.
Second, for enterprises that need predictable performance and security for their business-critical applications, such as retailers concerned with security and predictability for their PoS traffic, enterprise PCNs offer a dedicated network that helps prioritize business-critical applications.
Third, for enterprises such as K-12 schools or universities looking to extend their network outside buildings, either to temporarily add capacity to large venues such as stadiums, or to expand their wireless coverage to adjacent neighborhoods for distance learning, enterprise PCNs offer an affordable alternative. This is the case for the third-largest school district in the state of California, the Fresno Unified School District (FUSD) in Fresno, California, where the pandemic highlighted the digital divide for students in underserved neighborhoods and rural farming communities. FUSD is utilizing CBRS to deploy a private LTE network on 15 campus buildings as towers that can serve up to 10,000 students, and the district plans to double the scope of the network to deliver high-speed access to neighborhoods and communities that lack fiber and broadband connectivity. This is a trailblazing effort that is sure to be a model for thousands of school districts across the nation.
The considerations
Enterprises that are ready to embark on their PCN journey should prioritize several considerations before building the network. The deployment complexity and cost vary significantly among PCN vendors in the market and must be an important consideration when evaluating solutions. Many incumbents still depend on heavy professional services and planning, which increase complexity and cost, as well as extend timelines for new projects. Vendors that are leveraging public cloud infrastructure to minimize on-prem hardware, and have built-in tools for planning and SIM management, have a clear advantage here.
Secondly, the ability to run the PCN network as an integral part of the enterprise IT infrastructure – by leveraging existing tools for authentication, security, and policy – is critical to minimize risks over time. Integration with existing cybersecurity tools broadly deployed in enterprises, as well as a well-defined roadmap towards the evolving access security transition known as Secure Access Service Edge (SASE), is critical. A sub-optimal architecture is likely to increase ongoing operational costs over the lifetime of the network.
Thirdly, it is important to seamlessly transition existing IP network prioritization and controls back and forth with the enterprise PCN network to ensure consistent traffic behavior and avoid security loopholes. The control mechanisms in place should extend the contextual policy framework to prioritize network behavior based on user identity, device, location, and application to the enterprise PCN network.
Lastly, the PCN network should offer integrated end-to-end visibility and automation to enable fast troubleshooting of potential issues by an IT administrator or an IT VAR, with little to no cellular expertise. This can be accomplished by leveraging recent advancements in machine learning and public cloud infrastructure technologies.
Outlook for the future
The convergence of 5G, IT, and OT, coupled with an increasing diversity of critical mobile/IoT applications, is likely to drive private cellular connectivity much faster into enterprise environments as a complement to Wi-Fi. CBRS represents the most significant industry innovation within enterprise networking since the invention of Wi-Fi and will have a broad-reaching transformational impact on enterprise networking over the next several years.
