Satisfying Network Slicing Constraints via 5G MAC Scheduling

Network slicing provides a key functionality in emerging 5G networks, and offers flexibility in creating customized virtual networks and supporting different services on a common physical infrastructure. This capability critically relies on a MAC scheduler to deliver performance targets in terms of aggregate rates or resource shares for the various slices.A crucial challenge is to enforce such guarantees and performance isolation while allowing flexible sharing to avoid resource fragmentation and fully harness channel variations. In the present paper we propose a MAC scheduler which meets these objectives and preserves the basic structure of utility-based schedulers such as the Proportional Fair algorithm in terms of per-user scheduling metrics. Specifically, the proposed scheme involves counters tracking the aggregate rate or resource allocations for the various slices against pre-specified targets, and computes offsets to the scheduling metrics accordingly. This design provides transparency with respect to other scheduling modules, such as link adaptation and beam-forming.We analytically establish that the proposed scheme achieves optimal overall throughput utility subject to the various slicing constraints. In addition, extensive 3GPP-compliant simulation experiments are conducted to assess the impact on best-effort applications and demonstrate substantial gains in overall throughput utility over baseline approaches.