Nintendo GameCube Broadband Adapter and Modem Adapter

The Nintendo GameCube Broadband Adapter and Modem Adapter are a network adapter and 56k dial-up modem, respectively, for the GameCube. They were produced by Conexant and made in the Philippines and released in October 2002. The adapters fit flush into "Serial Port 1" on the underside of the GameCube and add a 8P8C (RJ-45) or 6P4C (RJ-11) port to the side of the console.

^ a LAN games can be played on the Internet with third-party PC applications such as Warp Pipe and XLink Kai that allows online play of these three games by tunneling the network traffic through a computer and across the Internet.

Soon after Phantasy Star Online Episode I & II was released for the GameCube, it was discovered that a PC could be made to simulate the conditions of the server that the game would connect to. This information started as a method of the online service. When simulating this server, unsigned code can be streamed back to the GameCube, allowing homebrew, or information to be streamed back, allowing one to play copied games. This was also utilized to allow online gameplay in games for which it is not intended. Early dumps of GameCube games were created using this technique. From there, methods of running the games off of a computer through a GameCube were created. Nintendo and Sega responded by releasing the Plus version of the game.

The online gaming service was officially discontinued in April 2007, in order to focus on the GameCube's successor, the Wii, and its online service which was eventually shut down in 2014. Although the GameCube's official online service was eventually discontinued, games can still be played online via private servers. Games with LAN multiplayer support can still be played in LAN mode as well, and can be played online via tunneling software.

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