L4S pulls this off by giving internet packets an indicator that lets them know if they’ve run into congestion or queueing along any of the hops in their trip between a user and whatever they’re connecting to. If there is a delay, then the devices can start to adjust to stop making the congestion worse — and possibly eliminate it entirely.

Jason Livingood, vice president of technology policy, product and standards at Comcast, told VentureBeat that they believe they can cut lag down from hundreds of milliseconds

Comcast Introduces Nation’s First Ultra-Low Lag Xfinity Internet Experience with Apple, Meta, NVIDIA, and Valve