Learning an adaptive forwarding strategy for mobile wireless networks: resource usage vs. latency

Mobile wireless networks present several challenges for any learning system, due to uncertain and variable device movement, a decentralized network architecture, and constraints on network resources. In this work, we use deep reinforcement learning (DRL) to learn a scalable and generalizable forwarding strategy for such networks. We make the following contributions: (i) we use hierarchical RL to design DRL packet agents rather than device agents to capture the packet forwarding decisions that are made over time and improve training efficiency; (ii) we use relational features to ensure generalizability of the learned forwarding strategy to a wide range of network dynamics and enable offline training; and (iii) we incorporate both forwarding goals and network resource considerations into packet decision-making by designing a weighted reward function. Our results show that the forwarding strategy used by our DRL packet agent often achieves a similar delay per packet delivered as the oracle forwarding strategy and almost always outperforms all other strategies (including state-of-the-art strategies) in terms of delay, even on scenarios on which the DRL agent was not trained.