This is a fascinating research, especially given the current security landscape of GPON deployments. Many local ISPs rely on hardware from Chinese vendors running vulnerable firmware, while even Tier 1 providers frequently lack downstream encryption and leave their GPON splitters unsecured in public.
More details here:
DEFCON Presentation Recording
https://www.gpwn.io
More details here:
DEFCON Presentation Recording
https://www.gpwn.io