Neutral host network sharing in cities can slash costs by up to 47% – study

Compared with traditional 5G small cell sites, neutral host networks used for 5G densification in cities can cut deployment costs by up to 47%, while slashing energy consumption by as much as 38%. These are the findings of an ABI Research study commissioned by neutral host company Boldyn Networks.

The savings are said to mainly arise from equipment consolidation, as well as the sharing of installation costs including small cell radios, fiber and power trenching, site maintenance and site leases, according to the study.  

Neutral host networks are a type of private network that can be shared by multiple parties, including service providers. This means that apart from serving the same use cases as other private networks, they can also be made available to carriers to extend their coverage, often indoors. They are typically deployed by third parties rather than operators themselves.

Model cities

ABI Research used its network model together with real-life data from different areas where neutral hosts are deployed, selecting five areas across two cities to model the benefits. In New York, it focused on Manhattan as a dense urban area, Brooklyn as an urban location and the Bronx as a suburban zone. One urban and one suburban section were picked in Rome. 

In New York, Boldyn has started building the Link5G project, a small cell deployment which supports public Wi-Fi and densification, and can host three operators. It has also been tapped by the city's Metropolitan Transportation Authority (MTA) to provide cellular connectivity to public transport tunnels. 

The Italian capital, meanwhile, plans a shared 5G small cell network based on neutral host, which will also support smart city applications. Boldyn has also been tasked with delivering shared connectivity to the public transport system ahead of the papal jubilee, the firm's chief operating officer, Brendan O'Reilly, said during a virtual press briefing outlining the study's results.

Speaking about the methodology, ABI Research's senior research director, Dimitris Mavrakis, said "we've used a MOCN – a multi-operator core network sharing model – and typical 5G radios deployed in these scenarios up to 100 megahertz of bandwidth," adding this represents "very recent infrastructure and deployment models, the very same ones that the actual operators are using to deploy their networks in these areas."

Apart from the MOCN sharing model, which ABI Research says is the more efficient one for most scenarios, the study also notes the multi-operator radio access network (MORAN) model can be used. This cuts down on complexity and need for coordination, but reduces spectrum efficiency.

Dense and denser

The goal of the study was to quantify the benefits of neutral host deployments, with Mavrakis saying that although there has been a lot of discussion about this topic, no one has conducted similar research. 

(Source: ABI Research)

Interestingly, the results suggest that while density matters when it comes to cost and energy savings, it is in less populated areas that operators can realize the biggest savings.

While this may appear counterintuitive, the reason is that a single small cell covers around 1.4km and 200 simultaneous users, far below what's needed in highly populated areas, according to the study. As a result, more small cells have to be deployed, reducing the overall savings.

The results suggest that costs fall by 47% in four out of the five scenarios modeled, with Manhattan dense urban setting seeing a 40% decrease. Energy use, meanwhile, dropped by 38% in the suburban Rome scenario, with Manhattan again seeing the lowest reduction at 20%. During the presentation, Mavrakis indicated that energy costs are not included in the modeled cost savings.

(Source: ABI Research)

The total energy and costs saved in dense urban and urban areas are expected to be higher than in suburban areas, according to the study. This is because there will likely be more of these deployments as they also address concerns like deployment time and aesthetics. At greenfield sites in suburban areas, meanwhile, there are smaller capex savings to realize because fiber infrastructure tends to be less dense.

The model assumes that, on average, the neutral host network is shared by 2.4 operators, which would in practice mean two or three operators per site, Mavrakis said. A higher figure would mean greater savings.

The concept of a neutral host network seems to be expanding to uses other than mobile network coverage. During the presentation, O'Reilly said Boldyn is deploying a LoRaWAN network – a low-power wide-area network for IoT communication – for the UK city of Sunderland, which will act as the anchor tenant, with MNO connectivity provided on top of that network. 

In Rome, the company is looking at deploying a public Wi-Fi network and sensors for city management purposes. In New York, meanwhile, the Link5G project also supports digital displays to give information to commuters and provide access to emergency services.

Demand for data in cities (and elsewhere) has been growing, and this has been exacerbated by fixed wireless access deployments (FWA), which have been contributing to congestion, according to Mavrakis. Meanwhile, operators are eager to keep capex to a minimum, and adding sites in dense urban areas can be a costly process. The financial and energy savings involved may present a compelling case to operators.