I'm trying to understand some OTN concepts that are not immediately obvious from the G.709 standard documents.

I'm curious about the case of Ethernet frames packaged into ODU frames.

  1. in case the fixed line-rate of the OTN link (e.g. supporting 100GbE) is not utilized fully, because the Ethernet datastream is of lower data-rate, how is the remaining 4x3808 byte OPUk payload filled? With dummy data? Or is it done via "idle frames (to fill the link when no IP packet or Ethernet frame is available)" as I'm reading here about GFP.

  2. Let's say an entire OTN frame could not be decoded post FEC: I assume the entire frame is trashed and no garbage data will be put onto the Ethernet side (correct?). What happens to an Ethernet frame that was distributed across a decoded OTN frame and an un-decoded OTN frame? According to this answer, they should be discarded anyways at the next switch/router if they are at all generated.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Browse other questions tagged or ask your own question.