MAC protocol requirements for OFDMA-PONs
This paper provides specifications of the parameters defining the design of medium access control (MAC) protocols for orthogonal frequency division multiple access (OFDMA) passive optical networks (PONs). A dynamic bandwidth allocation (DBA) algorithm exhibiting service level agreement (SLA) has displayed packet delays of less than 1.5 ms for the middle and high SLA optical network units (ONUs) at 156 Mbps, representing the maximum ONU offered load. A spectral efficiency of 93.75% the total network capacity of 40 Gbps has been achieved, for 256 ONUs and long-reach link lengths of 100 km. The new protocol functionalities have been attained by the extension of the XG-PON frame structure to demonstrate OFDMA/TDMA granularity.