What is Metropolitan Ethernet (Metro Ethernet)?
Metropolitan Ethernet (Metro Ethernet) refers to the use of Carrier Ethernet technology in metropolitan networks. Businesses, academic institutions, and government agencies in major cities use Metro Ethernet to connect branch offices and offices to the Internet. In other words, Metro Ethernet connects business local area networks (LAN) and end users to wide area networks (WAN) or the Internet.
Metro Ethernet is a service provider collection of Layer 2 or Layer 3 switches or routers that are connected via fiber optics. The topology can be a ring, hub and star or a full or partial network.
Metro Ethernet can be used as pure Ethernet via synchronous digital hierarchy (SDH), Ethernet via Multiprotocol Label Switching (MPLS) or Ethernet via dense wavelength division multiplexing (DWDM). Ethernet-only implementations are less expensive, but also less scalable and reliable. Therefore, they are also limited to small and experimental deployments. SDH-based deployments are useful when there is an established SDH infrastructure that is used by large service providers.
The feasibility of Metro Ethernet grew in the late 1990s due to new technological developments that enabled transparent tunneling through virtual LANs as point-to-point or multipoint-to-multipoint circuits.
Metro Ethernet is often used for small deployments with fewer than a few hundred customers.
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