Recommendation ITU-T G.987.3 describes the transmission convergence layer for 10‑gigabit‑capable passive optical network systems – a family of flexible access network systems that operate over a point-to-multipoint optical access infrastructure at nominal data rates in the order of 10.0 Gbit/s in at least one direction, while providing a wide range of broadband and narrow-band services to end-users. The 2025 Revision of the Recommendation ITU-T G.987.3 builds upon its 2014 Revision, as amended in 03/2020 and 05/2021, implementing the TC layer consistency updates across the ITU-T PON specifications and providing routine maintenance fixes.