Transparent LAN service between two sites 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.
While a transparent LAN connection has been established between two sites, implementing multipoint transparent LANs has proven difficult because of the contrasting network architectures: one based on broadcast-style Ethernet and the other on point-to-point connections.