A Greener Experience: Trade-Offs between QoE and CO₂ Emissions in Today's and 6G Networks

While users of Internet multimedia services demand high Quality of Experience (QoE), meeting these demands results in energy consumption along the service delivery path, from the end user's device, through the network to the service infrastructure (e.g., in a cloud). This energy consumption typically implies carbon dioxide (CO₂) emissions, which are a primary driver of climate change. One contribution of this article is to quantify and illustrate the trade-off between the QoE of video streaming services and CO₂ emissions. Kleinrock's power metric from queuing theory is applied to find operational points and recommended video bitrates of the QoE-sustainability trade-off. Furthermore, considering that networks and service delivery infrastructures are still in the process of transitioning towards 'green energy' consumption, we investigate the impact of 'green users' accepting certain quality degradations so as to reduce CO₂ emissions.