FluidRAN: Optimized vRAN/MEC Orchestration

TLDR

vRAN decouples base station functions from radio units, enabling cost‑efficient central unit pooling and flexible split selection that relaxes network requirements compared to fully centralized C‑RAN, while MEC services favor distributed RAN architectures. This work investigates the challenging vRAN design problem and proposes a joint vRAN/MEC solution that minimizes operational costs while meeting MEC requirements. The authors introduce FluidRAN, a data‑driven analytical framework that jointly selects split options and RU‑CU routing paths, evaluated on topologies from three operational networks and extended to MEC scenarios. Results show that pure C‑RAN is rarely a viable upgrade, FluidRAN yields substantial cost savings over D‑RAN, and MEC can raise operator costs by shifting vRAN functions back to radio units.

Abstract

Virtualized Radio Access Network (vRAN) architectures constitute a promising solution for the densification needs of 5G networks, as they decouple Base Stations (BUs) functions from Radio Units (RUs) allowing the processing power to be pooled at cost-efficient Central Units (CUs). vRAN facilitates the flexible function relocation (split selection), and therefore enables splits with less stringent network requirements compared to state-of-the-art fully Centralized (C-RAN) systems. In this paper, we study the important and challenging vRAN design problem. We propose a novel modeling approach and a rigorous analytical framework, FluidRAN, that minimizes RAN costs by jointly selecting the splits and the RUs-CUs routing paths. We also consider the increasingly relevant scenario where the RAN needs to support multi-access edge computing (MEC) services, that naturally favor distributed RAN (D-RAN) architectures. Our framework provides a joint vRAN/MEC solution that minimizes operational costs while satisfying the MEC needs. We follow a data-driven evaluation method, using topologies of 3 operational networks. Our results reveal that (i) pure C-RAN is rarely a feasible upgrade solution for existing infrastructure, (ii) FluidRAN achieves significant cost savings compared to D-RAN systems, and (iii) MEC can increase substantially the operator's cost as it pushes vRAN function placement back to RUs.