Ethernet has become a prominent candidate for the infrastructure of an IP-based packet centric network infrastructure, providing not only for enterprise services that are virtual private networks but also for residential services that are FTTx and xDSL for triple play. To construct a service providerpsilas network by using layer two (L2) switches in the wide area network (WAN) certainly represents an economical solution for providing Ethernet connectivity to end users. However, management of Ethernet networks with carrier-class reliability is generally a difficult issue for operators and service providers since there is almost no operation, administration and maintenance (OAM) capability in the network. This paper proposes an OAM architecture for an Ethernet network using a standard-based Ethernet OAM functionality, which is defined by IEEE, ITU-T and MEF. A framework of maintenance level that is an important concept of hierarchical Ethernet management is applied to the wide area Ethernet service configuration. According to the concept, we have successfully demonstrated standard-based Ethernet OAM functionalities, namely loop back, delay measurement and link trace, with several scenarios that may occur during actual operation.