5G neutral host networks fill enterprise gaps

By: Stuart Strickland, Wireless CTO and Fellow, HPE Aruba Networking and Pingping Zong, Senior Distinguished Technologist, HPE Aruba Networking

As we discussed in an earlier post, over the coming years private cellular is expected to join enterprise Wi-Fi in delivering wireless mobility. Regulatory and technological factors have converged to make private cellular an attractive solution to specific enterprise networking needs.

In this post, we’ll expand upon an opportunity to leverage private 5G (and LTE) to solve a common challenge faced by the vast majority of enterprises — gaps in public cellular coverage that inhibit business productivity, frustrate employees, and degrade visitor experiences — by using neutral host technology.

A “neutral host” can accept all clients, rather than only those with credentials from a single service provider, by acting as a shared resource that does not depend on licensed spectrum from a single company. Although public Wi-Fi is the epitome of the neutral host concept, there are distinct advantages to using a private cellular network to enable this capability within the enterprise. But, before we jump to specific solutions, let’s consider the extent of the problem, using healthcare institutions as an example.

The typical hospital or healthcare clinic supports communication among a complex community of patients, visitors, staff, office machines, and medical equipment. Some are permanent fixtures of the institution, others are transient guests, and still, others are regular visitors, such as clinicians.

While Wi-Fi carries much of the internal traffic at healthcare institutions, most visitors and staff members enter facilities carrying their mobile phones as their primary means of communication with each other and the outside world. However, an increasingly common problem is a lack of reliable cellular network coverage in these buildings. Substantial gaps in public network coverage inhibit patient communication with their families, block urgent communication among staff, and delay resolution of routine service calls from visiting technicians.

What causes public cellular gaps?

Given that enterprises and users have come to depend on both Wi-Fi and cellular, here’s what’s known about the causes of public cellular coverage gaps:

• Energy efficiency improvements are essential to protecting our environment, but prevent signals generated by outdoor cellular towers from penetrating thicker walls, multi-pane windows with thermal coatings, and improved roofing materials. As building efficiency increases, the traditional model of delivering public network coverage indoors from cell towers outdoors is breaking down.
• Densification of public cellular networks is a movement driven by both the escalating demand for capacity and a need for greater network energy efficiency. The most efficient way to increase the capacity of a cellular network is to make it denser by moving towers closer together. In a denser network, however, each tower can serve fewer clients with the same resources. Each tower must also transmit at lower power levels to avoid interference with its neighboring towers. For nearby outdoor clients, this results in a much better experience. But these lower-power signals have an even tougher time penetrating building walls.
• Limited coverage in rural areas. Public networks depend upon economies of scale. So we see a lot of investment in urban areas where dense networks can serve dense populations of paid subscribers. Outside urban population centers, the cost of improving coverage often exceeds the prospects for revenue, leaving gaps in coverage that no mobile network operator is incentivized to close.

DAS: The legacy answer

Until now, the most established solution for the mobile network operators to provide reliable public cellular connectivity inside of a building or venue has been a distributed antenna system (DAS). At a high level, a DAS system is comprised of a network of antennas placed throughout a building or venue. Each antenna is connected via fiber optical cable to the mobile operators’ baseband processing units, which are normally installed in the basement.

In order to provide coverage for multiple operators’ public cellular connectivity, a DAS system must support multiple cellular frequency bands as well as multiple cellular technologies when required by the operators. The enterprise, or an entity managing the DAS system, must generally work closely with multiple mobile network operators to address the radio planning and coverage optimization during the deployment of the DAS system.

The high deployment cost, complex fiber cabling required, and multi-party involvement have limited the viability of DAS mostly to large public venues (LPVs) and airports, where the benefits could outweigh the costs.

The rise of 5G neutral host network

A private 5G network operating in shared spectrum, such as Citizens Broadband Radio Service (CBRS) in the US, and supporting a 3rd Generation Partnership Project (3GPP) Multi-Operator Core Network (MOCN)-based network sharing solution can offer an attractive alternative to DAS.

Commonly described as a 5G neutral host network, a privately deployed 5G network in this configuration provides 5G coverage to the mobile subscribers of any number of mobile network operators (MNOs), as if the subscriber were within its operator’s own area of network coverage. The figure below highlights the key differences between a neutral host-based in-building solution and a DAS-based in-building solution:

• In order to support multiple MNOs, a neutral host solution only needs to support a single frequency range dedicated to the local deployment. This will translate to cost savings and simpler radio frequency (RF) planning. A DAS solution must support multiple MNO-specific frequency ranges.
• In addition to extending the MNO’s public cellular coverage inside the building, a neutral host network also operates as a standalone private 5G network, under enterprise control and serving enterprise users and business objectives. This is not possible with a DAS solution.

HPE Aruba Networking

Fully integrated neutral hosts: An attractive solution

Networking suppliers like HPE Aruba Networking are developing fully integrated neutral host solutions to make them attractive to enterprises in the following aspects:

Eliminates contract burdens. Rather than leaving the burden on an enterprise, or independent DAS operators, to negotiate contracts with each participating mobile network operator for each of its individual venues at multiple locations, leading enterprise networking suppliers are actively working to negotiate umbrella agreements with cellular network operators. This will allow inbound roaming across their entire global footprint, streamlining and simplifying the process of adopting and deploying enterprise 5G neutral host solutions.

Returns control to the enterprise. Within the framework of DAS systems, the constant direct involvement of multiple MNOs in network management leaves the enterprise with very little visibility or control. This includes RF planning and optimization, on-site MNO equipment management, and hardware/software upgrading. Further, the enterprise has no visibility and control of DAS-based in-building coverage performance or data analytics because the network performance data is collected and owned by the MNOs.

With a 5G neutral host network, the enterprise deploys and manages its own private network, or selects managed service providers to perform this work on its behalf and in its interests. Within the neutral host framework, the enterprise has full visibility and control over feature selection, hardware/software upgrading, performance analytics, and network optimization, all of which are key to satisfying users and ensuring operational efficiency.

Reduces infrastructure complexity and cost. As noted in the previous post, cellular networks have their own set of connectivity protocols and operating requirements. However, enterprise networking suppliers are developing solutions that streamline and integrate private cellular, providing IT departments with familiar tools.

The most advanced solutions will fold cellular management into the same AIOps-enabled administrative layer as the accompanying wired and wireless infrastructure, such as with HPE Aruba Networking Central, for intelligent, automated, unified, and centralized administration.

A bright future

Overall, there is growing excitement within the enterprise networking industry for the opportunities that private cellular networks, including neutral cellular hosts, present for addressing enterprise connectivity concerns. Whether it’s providing mobility in challenging environments, cost-effectively covering large outdoor areas, or filling gaps in public cellular services within the enterprise, you’ll certainly be hearing more about private 5G as an integral component of enterprise networking strategies.

Meanwhile, you can learn more about private cellular solutions and how to leverage them in your enterprise by consulting What is Private 5G?, our handy guide to this new opportunity to improve experiences, increase productivity, and reduce costs at your company.