Recommendation ITU-T G.798 specifies both the components and the methodology that should be used in order to specify the optical transport network (OTN) functionality of network elements; it does not specify individual optical transport network equipment. Amendment 3 to Recommendation ITU-T G.798 (2023) – completes defects and generic processes specification for fgOTN and FlexO regenerator functionality; – aligns the deskew capability of short-reach FlexO interfaces to latest G.709.5; – adds support for adaptation of fgODUflex to multiple PDH path clients; – corrects various functional mistakes; – makes some editorial changes.