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 the nominal data rates on the order of 10.0 Gbit/s in at least one direction, while providing a wide range of broadband and narrow-band services to the end-users.

The original Additional Review text of ITU-T G.987.3 contained a typographical error. Revision 1 of the AR text adds the following immediately after the first sentence in clause 6.2.2: "The frame formats are devised so that the frames and their elements are aligned to 4-byte word boundaries whenever possible."