Main Question or Discussion Point
GFP and OTN, both are encapsulating data traffic of different types (IP, Ethernet etc.) into one frame and the GFP layer lies above the SONET/SDH and OTN layer. So, I am confused about how this works? We encapsulate data in GFP to encapsulate it further in OTN? Whereas SONET/SDH are multiplexing protocols...?