Gentoo Network APpliance
"The acronym GNAP stands for Gentoo Network APpliance. It's an easy way to build stateless network appliances (firewalls, routers...) for old or embedded configurations without the need for a full installation.
A GNAP is a LiveCD, much like Knoppix, geared toward routing services like firewalling, traffic profiling, VPN and network monitoring. Specific configuration files are burnt onto the LiveCD to customize its behaviour, making it easy to restart, and impossible to permanently compromise.
It is also possible to install GNAP on a hard disk, DiskOnModule or CF card for embedded configurations."
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