Minimizing Age of Information in a Multihop Wireless Network

TL;DR

This paper introduces a distributed control policy for multihop wireless networks that effectively minimizes the age of information by combining scheduling, channel state awareness, and packet dropping, outperforming traditional methods.

Contribution

It proposes a novel distributed scheduling and packet dropping policy that reduces age of information and achieves near-optimal performance in multihop wireless networks.

Findings

Dropping older packets reduces average age below LCFS scheduling.

The policy achieves age close to the theoretical lower bound.

State-aware scheduling significantly improves performance.

Abstract

We consider the problem of minimizing age in a multihop wireless network. There are multiple source-destination pairs, transmitting data through multiple wireless channels, over multiple hops. We propose a network control policy which consists of a distributed scheduling algorithm, utilizing channel state information and queue lengths at each link, in combination with a packet dropping rule. Dropping of older packets locally at queues is seen to reduce the average age of flows, even below what can be achieved by Last Come First Served (LCFS) scheduling. Dropping of older packets also allows us to use the network without congestion, irrespective of the rate at which updates are generated. Furthermore, exploiting system state information substantially improves performance. The proposed scheduling policy obtains average age values close to a theoretical lower bound as well.