Nintendo of America

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Nintendo GameCube - LAN - Frequently Asked Questions
  1. What does LAN mean? Does this mean that Mario Kart: Double Dash can be played online?
    A Local Area Network (LAN) means that two or more devices are directly connected--either via wires or a wireless connection--to exchange data. A LAN connection with Nintendo GameCubes does not need an internet connection, as the games are not played online.

  2. Do I need the Modem Adapter or the Broadband Adapter for my Nintendo GameCube?
    Because an ethernet or crossover cord is needed for this feature, players will have to have a Broadband Adapter on each Nintendo GameCube. The Modem Adapter uses a standard phone cord, making it incompatible for LAN use.