IS OTN and MS OTN Only Supported By Line and Tributary Boards Or OTU Board as well?

Dear friend!
For the first question:
In MS OTN and OTN subracks where electrical cross-connect boards are installed, tributary boards, line boards, and tributary-line boards are installed. In MS OTN and OTN subracks where electrical cross-connect boards are installed, only tributary-line boards are supported.

For the second question:
Whether an OTU board supports OTN and MS OTN depends on the board model.OTU boards can be installed in OTN and MS OTN subtracts. Some OTU boards, however, support only a few types of services. For example, the OTU boards may not support packet services.

For the third question
The OTU board can map client signals to ODUk signals.

For the fourth question

The universal line board supports three types of signals.(packet signals, SDH signals, and ODU signals)Conversion between OTU signals. The common line board supports the conversion between ODU signals and OTU signals.

When a universal line board is used, the cross-connect board that supports packet services and SDH services must be installed. If the subrack is configured with common line boards, you only need to install the cross-connect boards that support ODU signals.

Thank you!