AuDSL - a software leased line modem

AuDSL is an experimental software modem for low-speed Internet connectivity over leased copper lines using PC sound cards as the line interface. The acronym AuDSL stands for Audio Digital Subscriber Line.

A prototype installation of AuDSL has achieved a speed of 96 kilobits per second, full duplex, over several kilometers of two-wire copper leased line.

Please note: the AuDSL software was written and released in 1999, when leased-line modems were relatively expensive and commercial DSL service and equipment were not yet widely available. It has not been actively maintained since then. It is not compatible with standard central office ADSL equipment, but requires a soundcard-equipped PC at both ends of the "last mile" copper connection. For these and other reasons, it is not a viable alternative to an ADSL modem for most users. It is mainly of interest as a technological curiosity and as a source of code, algorithms, and inspiration for other open-source softmodem projects.

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Andreas Gustafsson,