Enabling next Generation Ethernet Access with Ethernet Passive Optical Networks

This article describes Ethernet Passive Optical Networks (EPONs), an emerging local subscriber access architecture that combines low cost point-to-multipoint fiber infrastructure with Ethernet. EPONs are designed to carry Ethernet frames at standard Ethernet rates. EPONs use a single trunk fiber that extends from a central office to a passive optical splitter, which then fans out to multiple optical drop fibers connected to subscriber nodes. Other than the end terminating equipment, no component in the network requires electrical power, hence the term passive. Local carriers have long been interested in passive optical networks for the benefits they offer: minimal fiber infrastructure and no powering requirement in the outside plant. With Ethernet now emerging as the protocol of choice for carrying IP traffic in the Metro and Access network, EPON has emerged as a potentially optimal architecture for fiber to the building and fiber to the home.