An Optical Line Terminal (OLT) includes a downstream transceiver coupled to a Passive Optical Network (PON). The downstream transceiver is configured to communicate over a plurality of bonded channels. The OLT also includes an upstream transceiver configured to receive a downstream Service Data Unit (SDU) including user data. A processor is coupled to the upstream transceiver. The processor is configured to split the downstream SDU into a plurality of downstream blocks. The processor distributes the downstream blocks amongst the bonded channels based on bonded channel availability for transmission over the PON via the downstream transceiver.