transparent LAN service(redirected from TLAN)
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transparent LAN serviceA service from a carrier that links remote Ethernets together. It is called "transparent" because the connected Ethernets are viewed as one Ethernet by the customer, regardless of the technology employed by the carrier in between.
Transparent LAN service between two sites, more accurately known as a "LAN interconnect," has been successful, but multipoint transparent LANs have been problematic due to the difference in architecture between the broadcast-based Ethernet and the carrier's point-to-point network. The VPLS standard was developed to resolve the problem using IP and MPLS routers (see VPLS). See VPN.