Emulated local area network (ELAN)
A logical ATM network that emulates the services of an Ethernet or Token Ring LAN. That enables intelligent devices with ATM connections to communicate with remote LAN-connected devices as if they were directly connected to the LAN.

Transparent LAN service (TLAN)
A 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

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