# Validating a 5G-Enabled Neutral Host Framework in City-Wide Deployments
###### Abstract  
Along with the adoption of 5G, the development of neutral host solutions provides a unique opportunity for mobile networks operators to accommodate the needs of emerging use-cases and in the consolidation of new business models. By exploiting the concept of network slicing, as one key enabler in the transition to 5G, infrastructure and service providers can logically split a shared physical network into multiple isolated and customized networks to flexibly address the specific demands of those tenant slices. Motivated by this reality, the H2020 5 GCity project proposed a novel 5G-enabled neutral host framework for three European cities: Barcelona (ESP), Bristol (UK), and Lucca (IT). This article revises the main achievements and contributions of the 5 GCity project, focusing on the deployment and validation of the proposed framework. The developed neutral host framework encompasses two main parts: the infrastructure and the software platform. A detailed description of the framework implementation, in terms of functional capabilities and practical implications of city-wide deployments, is provided in this article. This work also presents the performance evaluation of the proposed solution during the implementation of real vertical use cases. Obtained results validate the feasibility of the neutral host model and the proposed framework to be deployed in city-wide 5G infrastructures. 2020 October 2021 December 2021 202  
integration and deployment of such enablers, as well as in the evaluation of business feasibility and sustainability. Enabled by the introduction of network slicing in 5G [6], the neutral host model is changing the whole telecommunication business ecosystem by transforming the traditional market to be more pervasive and open to new opportunities for infrastructure and service providers [7]. Under the neutral host model, infrastructure and service providers can find new ways to monetize their services and share the cost of infrastructure upgrade (capital expenditure (CAPEX)) and ensure a quick return of investments (ROI) and business sustainability [8]. Several private and public initiatives are supporting research and innovation projects to deal with challenges for 5G technology realization (5G Public Private Partnership (5G PPP) in Europe [9] and the International Mobile Telecommunication 2020 (IMT2020) at International Telecommunication Union (ITU) [10]. However, few projects in the ecosystem are focused on infrastructure sharing and business changes to improve, integrate, and demonstrate 5G neutral hosting capabilities in a hyper-connected city infrastructure with real use cases. Hence, as part of 5 GPPP and European Commission (EC) Horizon 2020 (H2020) initiatives, the 5 GCity project [11] focused on the design, development, deployment, and validation of a novel 5G-enabled neutral host framework for real-world deployments in three European cities: Barcelona (ESP), Bristol (UK), and Lucca (IT). In this article, we refer to the term 5G-enabled neutral host framework to define a system capable of dynamically managing and orchestrating a virtualized network infrastructure to allocate 5G services with disparate requirements for multiple relevant stakeholders. The 5G-enabled neutral host framework provides multitenancy to a city-wide deployment by realizing and combining enhancements of 5G enabling technologies required by the neutral host model. This article revises the main achievements and contributions of the 5 GCity project, focusing on the deployment and validation of the proposed 5G-enabled neutral host framework in the three aforementioned cities. The developed neutral host framework consists of a software platform for slicing and orchestrating computing and network resources from a 5G-enabled cloud, edge, and radio infrastructure. A detailed description of the framework implementation, in terms of functional capabilities and practical implications in city-wide deployments, is described in this work.