The Ethernet passive optical network (EPON) system is a general name for PON systems that are based on the IEEE 802.3 standard and the IEEE 1904.1 standard. This Recommendation focuses on EPON systems that apply the ONU management and control interface (OMCI) defined by [ITU-T G.988] to create an effective PON operation system. This Recommendation calls these EPON systems OMCI-EPON. OMCI-EPON includes 1G-EPON@ 10/1G-EPON and 10/10G-EPON architectures defined in [IEEE 802.3]. The requirements and specifications of OMCI-EPON conform to [IEEE 802.3] and the IEEE 1904.1 Package B standard and to the operational requirements and specifications defined by Annex C of [ITU-T G.988]. The requirements and specifications of OMCI-EPON enable the use of OMCI to manage IEEE 802.3/IEEE 1904.1 Package B compliant systems@ thus providing 1G-EPON and 10G-EPON solutions to network operators who prefer OMCI management. As much as possible@ this Recommendation maintains backward compatibility with existing optical distribution networks (ODN) that comply with the existing PON systems defined by [IEEE 802.3] and ITU-T Recommendations such as [b-ITU-T G.983.x]@ [b-ITU-T G.984.x] and [b-ITU-T G.987.x]. Furthermore@ this Recommendation provides a mechanism that enables coexistence with the existing PON systems using TDMA technologies and/or wavelength blocking filter (WBF).