This Recommendation specifies mechanisms required to operate and maintain the network and service aspects of the ETH layer. It also specifies the Ethernet OAM frame formats and syntax and semantics of OAM frame fields. The OAM mechanisms as described in this Recommendation apply to both point-to-point ETH connections and multipoint ETH connectivity. The OAM mechanisms as described in this Recommendation are applicable to any environment independently of how the ETH layer is managed (e.g., using network management systems or operational support systems). The architectural basis for this Recommendation is the Ethernet specification [ITU-T G.8010] which also accounts for [IEEE 802.1D], [IEEE 802.1Q], and [IEEE 802.3]. The OAM functions of the server layer networks used by the Ethernet network are not within the scope of this Recommendation. The OAM functions of the layers above the ETH layer are not within the scope of this Recommendation either.