Cable Sensors

It depends on what you're trying to do exactly. I see two possible use cases. In either case, it would be up to your software to take the lower "cable sensor" information and populate appropriate properties in the Redfish model. Regardless of the case, you do not need to populate every property. For example, if you go the Cable resource route, there's no requirement to support properties like LengthMeters, DownstreamName, and UpstreamName.

1) If your intent is to show SFP status information with regards to what is populated in a physical port, then that would be modeled as a "Port" resource. Within Port, there is an SFP property, which has Status/State.

2) If your intent is a more generalized cable status/inventory, then using the Cable resource off the service root would be the place to go.