Framework enables scalable multi-hop 5G NR sidelink mesh networking
SL-RFSIM: Enabling Scalable Multi-Hop 5G NR Sidelink Mesh Networking in OpenAirInterface
Networking and Internet Architecture
Summary
Connecting devices directly without going through cell towers is a growing feature in 5G networks, but making multiple devices relay signals efficiently is tricky. This paper presents SL-RFSIM, a tool added to existing 5G software that helps test and build these multi-hop device connections. It changes how signals are simulated to support many devices talking directly and works with common networking tools for better device-to-device communication. The authors tested their system in real setups to show how it works and where current limits exist. This open-source tool helps others experiment with future multi-hop 5G networks.
What this means in practice
- •For cellular network engineers: Test and develop multi-hop 5G sidelink protocols using an open-source, scalable simulation framework compatible with real 5G stacks.
- •For mesh network developers: Build and evaluate layered 5G-based mesh networks integrating multi-hop device communication and standard mesh routing protocols using the new platform.
Authors
Simone Pio Candido, Jin Yan, Jérôme Härri
Abstract
Recent 3GPP releases have extended 5G New Radio (NR) Sidelink (SL) to support device-to-device (D2D) relay and multi-hop capabilities. This paper presents SL-RFSIM, a component-based experimentation framework extending OpenAirInterface (OAI) with scalable multi-hop NR SL capabilities. SL-RFSIM replaces the legacy OAI RF simulator with a broker-based publish/subscribe architecture enabling arbitrary peer-to-peer connectivity while preserving compatibility with the OAI protocol stack. The framework further integrates pluggable mobility, propagation, reception, and monitoring services, and supports Layer-2 mesh networking through BATMAN-adv. Experimental evaluation on the SLICES-RI research infrastructure validates the proposed architecture through representative mesh networking scenarios and identifies the current software bottlenecks limiting scalability. SL-RFSIM provides an open-source foundation for reproducible experimental research on 5G NR SL and future multi-hop cellular mesh networks.