Being short sighted in its beliefs while lobbied on by entrenched traditional telecom players, the CTIA’s recent claims (in a letter to the FCC) bashing the popular shared spectrum approach to allocating cellular spectrum and exclusive spectrum use as a proven method is hardly a useful reference point to address the growing demands for better wireless connectivity.
Such an approach only advantages large, rich, service providers while stifling real innovation.
CTIA’s choice to attack a relatively small swath of spectrum, like CBRS, looks to point to its insecurities in seeing CBRS as a threat to the current telecom operations and a desire to monopolize the market.
Nothing could be further from the truth.
With a misguided understanding of the market demands from global enterprises and the desire to double down on conventional cellular operational models that do little to spur innovation or broaden access to new cellular technology, it is no surprise that the CTIA is struggling in an industry debate that requires clear understanding of the state of the cellular market today.
Context is key
The current cellular market is saturated with licensed spectrum owned by few dominating tier-1 mobile network operators (MNO). Meanwhile, tier-2 service providers lean heavily on these tier-1 MNOs to enable their service offering with elaborate roaming agreements. This has been the de facto operational model for several cellular wireless generations.
This represents an effective stranglehold by the tier-1 operators that clearly shows that they have ignored the need for improved indoor coverage that advance enterprise-specific use cases. As a result, individual enterprises who want to own and operate their own private cellular network are effectively held hostage.
But with the availability of CBRS based shared spectrum use, this has all changed– unleashing relentless innovation by enterprises that are digitally transforming their businesses.
Several countries around the world have recognized the need for locally issued private spectrum licenses and are granting them based on individual use within specific campuses.
The current state of shared spectrum allocations around the world
With CBRS, two broad usage patterns appear: city wide coverage and single, multi-site enterprise campus coverage. Fortunately, the shared spectrum model provides the best of both worlds.
Dynamic allocation of shared spectrum allows for new entrants to be easily accommodated while incumbents continue to use the spectrum when required. Fixed licensed spectrum allocation, good for nationwide coverage, are inherently non-adaptive and restrict the growth of private networks. Today, all service providers, including the tier-1 operators, can augment their licensed spectrum with the shared spectrum for their use.
Use cases should drive spectrum allocation models
Technologically, localized coverage catering the specific use cases, rather than generic connectivity, is a fundamental requirement for individual enterprises. Even within a given enterprise, it is location specific.
The dynamic allocation of spectrum provides much needed market flexibility rather than a single monolithic allocation approach which has proven to be littered with cost and complexity.
A vast majority of evolving use cases in the market are short range communications servicing specific applications that demand the deterministic connectivity that cellular technology delivers. This can only be addressed by low power shared spectrum particularly in congested urban settings.
Given the fact that radio and compute capacity within a cell will be fully occupied, using a high-powered cell is irrelevant to such scenarios. As a result, the use of lower power cellular access points allows for better load balancing across cells within an enterprise campus.
Better coverage needed
Meanwhile, indoor coverage remains a persistent problem that has not been effectively addressed by the current licensed deployments. This aspect will persist and cannot be addressed with the conventional approaches leaving enterprises to solve it themselves and with the availability of shared spectrum.
Fortunately, some public service providers are beginning to solve this indoor coverage problem using shared spectrum to extend their network coverage indoors over enterprise private wireless networks, another big benefit of CBRS.
Rural coverage with sparse populations has also faced diminishing returns being largely ignored due to financial restrictions as the use of licensed spectrum is simply not cost effective for a service provider.
In stark contrast, the shared spectrum model allows for individual small cells to be deployed where connectivity is needed without incurring a high overhead and organically evolve the network as extended coverage is needed.
Use cases for smart cities, requiring city-wide coverage with disparate traffic patterns and service level requirements will also be prohibitive without the availability of shared spectrum. Lower cost devices developed for use with the shared spectrum band eliminate the cost and complexity of supporting licensed cellular services, allowing for newer device form factors to enter the market. This helps commoditize cellular technology by increasing adoption and bringing it on par with Wi-Fi.
Usage of different networks vary widely and creating exclusive licenses prohibit effective sharing of available spectrum. Numerous studies have shown the at any point and time instant, looking at the full available spectrum for communications, only a fraction of available spectrum is actually used. This suggests that it is best to not allocate fixed spectrum licenses to any entity as long as the complexity of dynamic spectrum allocation management can be addressed.
The current CBRS model in the United States solves this precise problem.
In short, shared spectrum allows for continued use of the spectrum by the incumbent, which will no longer be possible if licensed allocations are made.
Shared spectrum models challenge conventional cellular wisdom
Exclusive use with smaller footprints requires extensive management from FCC and have only provided nationwide allocations. Introduction of CBRS allows for smaller footprint spectrum allocations, a fundamental enabler for enterprise deployments.
Service providers have purchased PAL spectrum licenses in the CBRS band and are finding ways to use it. This is still a struggle because they are used to a nationwide licensed spectrum model using their macro networks to deliver wide area coverage.
Current CBRS market deployments have shown to be very high performance, which none of the service providers have been able to deliver in an enterprise setting. This has become clearly apparent with the lack of indoor footprint, inability to reach the enterprise customer, and poor capacity management in smaller footprints using the nationwide spectrum allocations.
For enterprises the trend has been to move away from cloud compute and migrating network functions to enterprise edge MEC environments to support the real traffic patterns and application demands. As a result, the current service provider macro model has been ill-equipped to address this evolution.
Still, tier-1 service providers are finding creative ways to emerge from this including approaches leveraging the deployed private networks as neutral hosts and multi-credential support on the devices to extend their network footprint. Additionally, there is strong push towards enable public-private roaming to enhance their business models, which further acknowledges the growth of the private networks.
Conclusion
Ultimately, the message is: private networks are here to stay.
Guaranteeing high levels of service quality and security for discrete devices and applications, the typical demand of a private network, through wide area public network coverage has simply not proven effective.
Undoubtedly CBRS and spectrum sharing more than meets these requirements and is fundamental to enabling enterprises to capitalize on the innovation promise of private cellular wireless.
