Disruption-Free Load Balancing for Aerial Access Network

Abstract

A fundamental issue of 6G networks with aerial access networks (AAN) as a core component is that user devices will send high-volume traffic via AAN to backend servers. As such, it is critical to load balance such traffic such that it will not cause network congestion or disruption and affect users’ experience in 6G networks. Motivated by the success of software-defined networking-based load balancing, this paper proposes a novel system called Tigris, to load balance high-volume AAN traffic in 6G networks. Different from existing load balancing solutions in traditional networks, Tigris tackles the fundamental disruption-resistant challenge in 6G networks for avoiding disruption of continuing flows and the control-path update challenge for limiting the throughput of updating load balancing instructions. Tigris achieves disruption-free and low-control-path-cost load balancing for AAN traffic by developing an online algorithm to compute disruption-resistant, per-flow load balancing policies and a novel bottom-up algorithm to compile the per-flow policies into a highly compact rule set, which remains disruption-resistant and has a low control-path cost. We use extensive evaluation to demonstrate the efficiency and efficacy of Tigris to achieve zero disruption of continuing AAN flows and an extremely low control-path update overhead, while existing load balancing techniques in traditional networks such as ECMP cause high load variance and disrupt almost 100% continuing AAN flows.