SummitGbX enables Extreme Networks' Summit LAN switches to break through standard Gigabit Ethernet distance limitations. With SummitGbX, Gigabit Ethernet links are guaranteed up to 80 kilometers and can go to 100 kilometers or more, depending on the quality of the long-distance fiber-optic line. This allows the deployment of full-duplex Gigabit Ethernet over long distances via private or leased single-mode fiber-optic lines. Without SummitGbX, Gigabit Ethernet distances are only guaranteed up to 5 kilometers, which limits deployment in campus networks. SummitGbX extends Gigabit Ethernet distances across metropolitan area networks, making it an ideal solution for service providers.One SummitGbX is deployed at each end of a long-distance fiber-optic line. Each SummitGbX features a Gigabit Ethernet port to connect a local Summit LAN switch and a long distance interface set, which consists of one optical transmitter and one optical receiver port to connect to a SummitGbX at the other end of a fiber optic line. SummitGbX uses two signal paths - one from the Gigabit Ethernet interface to the long distance fiber interface and one from the long distance fiber interface to the Gigabit Ethernet interface. Each signal direction consists of an optical receiver, a clock/data recovery unit (CRU) and a transmitter. The CRU maximizes signal quality, thereby minimizing errors and optimizing cable length performance.