PacketFence is a fully supported, trusted, Free and Open Source network access control (NAC) solution. Boasting an impressive feature set including a captive-portal for registration and remediation, centralized wired and wireless management, 802.1X support, layer-2 isolation of problematic devices, integration with the Snort IDS and the Nessus vulnerability scanner; PacketFence can be used to effectively secure networks -- from small to very large heterogeneous networks.
Install PacketFence on Debian squeeze
To install it, you simply have to add the Inverse repository under /etc/apt/sources.list.d/ by adding the file packetfence.list containing:
deb http://inverse.ca/downloads/PacketFence/debian squeeze squeeze
sudo apt-key adv --keyserver keys.gnupg.net --recv-key 0x810273C4
sudo apt-get update
sudo apt-get install packetfence
Once apt-get finished to install all the packages, reboot your server and after please fire up your Web browser and go to http://@ip_packetfence:3000/configurator to complete your PacketFence configuration.
Check more details about configuration and usage from Packetfence documentation