This supplement describes different approaches for transport of 10GBASE-R signals, and one for 10GBASE-W signals, in optical transport networks via an ODU2 or non-standard ODU2-like frame format (i.e., rates, formats and mappings that are not defined in ITU-T Recommendations). This supplement includes descriptions related to multiplexing the non-standard ODU2-like structures into ODU3-like signals. Different attributes of the varying solutions are described to help provide guidance on which approaches are appropriate to which network contexts. Including a currently non-standard mapping in this supplement does not preclude considering that mapping for standardization at a future date.