eCPRI Supports In 5G O-RAN Fronthaul With FlexEthernet

Traditional Fronthaul architectures are not efficiently provisioned for 5G due to their lack of Fronthaul slicing supports or/and inability to satisfy the very strict latency and high bandwidth requirements defined for the enhanced common public radio interface (eCPRI). In this paper, we propose a new Fronthaul architecture that leverages Flex-Ethernet (FlexE) to guarantee 5G Fronthaul quality of service (QoS) requirements without over-provisioning the Fronthaul resources. By separating the MAC and PHY layers through a time division multiplexing (TDM) shim, FlexE allows for efficient aggregation of huge traffic volume and the design of low-latency hard network slicing architectures. Unfortunately, no standard has been defined for eCPRI transmission support over FlexE. Therefore, we propose a new protocol stack in which FlexE clients are efficiently allocated to carry eCPRI data of different 5G slices. We then formulate the FlexE-based Fronthaul provisioning optimization problem as an integer linear program (ILP) model. Simulation results show the proposed solution saves 82% of CAPEX and 94% of OPEX compared to a Fronthaul baseline.