Challenges and Opportunities for Global Cellular Connectivity

TL;DR

Global cellular connectivity remains fragmented by inter-operator trust, billing, and regulatory barriers. The authors survey the MVNO/MNA ecosystem and argue that Local Breakout (LBO) offers a viable path to native-like global service, while outlining the operational and policy challenges. Their contributions include a taxonomy and mapping of MNA breakout deployments, an in-depth analysis of LBO obstacles, and a discussion of architectural directions—such as zero-trust inter-operator frameworks, distributed ledgers, and DICE—for enabling global roaming. The work provides a practical roadmap toward scalable, low-latency global mobile access with implications for operators, regulators, and the broader device ecosystem.

Abstract

Traditional cellular service was designed for global connectivity, but business and logistical constraints led to its fragmentation, with deployments limited to individual countries and regions. Initiatives like Mobile Virtual Network Operators (MVNOs), Mobile Network Aggregators (MNAs), and regulations like ''roam-like-at-home'' have partially restored global service potential, though often at high costs in terms of user bills, application performance, and traffic efficiency. This paper makes two key contributions: first, it surveys the global cellular ecosystem, analyzing the strengths and weaknesses of major players using data from prior research, proprietary datasets, and public sources. Second, it argues that the technology for seamless global service exists in Local Breakout (LBO), a roaming architecture which allows user traffic to be routed directly to the Internet through the visited network, bypassing the home network and/or third-party infrastructures. However, LBO adoption is hindered by issues such as policy enforcement, billing, and Quality of Service (QoS) guarantees, rooted in a lack of trust between operators. The paper concludes by exploring technological advances that could enable LBO, and pave the way for truly global cellular connectivity.

Figures (3)

• Figure 1: Simplified 5G roaming architecture. Dashed lines: control plane traffic; solid lines: user plane traffic.
• Figure 2: Network operating models: MVNOs lacks ownership of radio spectrum resources; light/thick MVNOs rely on a single b-MNO, and the latter's roaming agreements for global service, while full MVNOs operate their own core network, and give global service through their own roaming agreements. MNAs run a limited part of the network (the light -- only sales $<<$ the thick -- limited core function $<<$ the full -- all the core), and provide global service by exploiting the roaming agreements of several b-MNOs.
• Figure 3: Map showing the geolocation of public internet gateways for various commercial eSIM providers—1NCE, Airalo, emnify, and Twilio—represented by different symbols. Colors denote the network providers hosting these gateway functions.