Businesses have long had wireless challenges that traditional technologies like Wi-Fi cannot address. Private LTE and 5G over free spectrum – like Citizens Broadband Radio Service or CBRS in the US – could help solve some of these problems.
Another compelling reason to use CBRS has emerged recently: neutral host networking. Neutral Host Networking is a low-cost architecture that uses private 5G to extend public carrier cellular signals to locations or areas of weak signal strength.
Here’s what businesses should know about neutral host networks and what they can do for both small and large businesses.
Improving cellular signal strength
Mobile voice and data networks have exploded since the advent of the smartphone, and access to these networks has become a must for businesses. However, a disadvantage of cellular networks is that they often struggle with limited signal penetration. When this problem occurs, carrier signals cannot reach certain areas within a corporate building or campus.
One way for companies to address this issue is to extend their carrier signal to areas of poor connectivity, said Srinivasan Balasubramanian, distinguished member of the CTO office and head of standards and IP at Celona Inc. Companies traditionally extend the signal using a signal Booster or Distributed Antenna System (DAS). While these methods work, they have their shortcomings.
According to Balasubramanian, boosters are only useful if the carrier signal is undistorted enough to amplify it. DAS, on the other hand, is an easier way for companies to extend their signal to all parts of a building, but the cost of implementation is prohibitive for most organizations.
“There are many scenarios where no solution solves this problem, and this is where the neutral host shines,” Balasubramanian said.
What is neutral host networking?
Host neutral networking is a way to spread public provider network access over a privately deployed wireless network. The technology leverages a building’s internal switching architecture along with private LTE or private 5G. Businesses can connect to carrier networks over the Internet using encrypted tunnels.
From there, network professionals can use the LAN and 5G radio access network (RAN) in the building or campus to propagate the signal over a private channel such as CBRS Band 48. Any CBRS-enabled mobile device can then access the public carrier network as if it were directly connected to it.
How neutral host networks work
Two or more mobile network operators (MNOs) can deploy neutral host networks by connecting to the corporate LAN over the Internet via an encrypted IPsec tunnel, Balasubramanian said. The tunnels end at the 5G RAN core gateway device. From there, the signal is routed securely over the corporate LAN and to 5G RAN access points deployed throughout the building.
The bearer signal then extends throughout the building over a CBRS channel, and the bearer traffic traverses the corporate network over a secure IPsec tunnel, Balasubramanian said.
“To ensure health and performance is maintained, key performance indicators will be shared between the 5G RAN core and service providers,” he said.
Who Should Use Neutral Host Networks?
New use cases for the provision of neutral host networks are emerging. One reason companies might consider deploying a neutral host network is if their facilities require public carrier connectivity to operate, Balasubramanian said. For example, the company could use a private 5G network internally and use the neutral host network to improve signal strength and capacity, he added.
Another use case he mentioned for neutral host networks is to grant employees or customers guest access to public networks. Some examples are college campuses, hospitals, and public or private venues.
“In these situations, public carrier access via neutral host networks can be the main driver for the deployment of a private 5G network, with the option to use private RAN as these opportunities arise,” he said.
In the past, these organizations would typically have deployed DAS, he said. Now they may prefer to use neutral host networks over 5G as a cheaper and more flexible alternative.
Neutral host networking outlook
Neutral host networks are not yet available in the US, but collaboration between private CBRS RAN manufacturers and nationwide cellular carriers is underway. For example, Celona is working with US carriers to broadcast public carrier services over CBRS bands. Other MNOs are working to develop neutral host networks around the world. In Europe, for example, Ericsson is working with Proptivity to launch the first neutral host network in Sweden as an indoor 5G service later in 2022.