Guy writes, "Matt Henderson has written a HiSax US ISDN Driver for Linux that allows the use of low cost passive ISDN cards. Based on the European version, this version includes the US National ISDN-1 (NI-1) protocol used throughout the USA and Canada. Combined with a low cost ISDN card, HiSax can turn a Linux machine into a powerful ISDN router and firewall at 64kbps or 128kbps. HiSax NI-1 drivers are available for 2.2 and 2.0 kernels..."

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