An IDLE insertion technique maps MPCP time onto an EPoC PHY. The techniques address the variability of bandwidth due to bit loading over time. The techniques allow MPCP time to follow wall time at the MAC layer while tracking bytes at the PMD layer. The techniques also facilitate use of the EPON MAC with few changes in an EPoC environment. The bandwidth allocation messages may follow the same format as in EPON, and the techniques may implement IDLE insertion that accounts for EPoC PHY FEC overhead and datarate differences compared to the MAC.