Epon system and method of traffic scheduling thereof

An EPON(Ethernet-Passive Optical Network) system and a traffic scheduling method therein are provided to cancel or minimize idle time and to obtain high bandwidth utilization by revising a dynamical bandwidth allocation method in an EPON system and previously providing information about the next EF(Expedited Forwarding) cycle at the initial cycle. An OLT(Optical Line Terminal) executes bandwidth allocation for EF#2 as well as EF#1 and AF#1 at the initial cycle. The allocated bandwidths are transmitted to ONUs(Optical Network Units) through gates. Each of the ONUs transmits data and a report to the OLT according to each allocated bandwidth. At this moment, each of the ONUs consecutively transmits not only EF#1 traffic and AF#1 traffic, but also EF#2 traffic to the OLT. The OLT executes dynamical bandwidth allocation after receiving a report transmitted together with AF#1 traffic from each ONU. In other words, the OLT executes dynamical bandwidth allocation for the next cycle as soon as EF#2 traffic is received from each ONU.