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Using a Linux L2TP/IPsec VPN server - http://www.jacco2.dds.nl/networking/freeswan-l2tp.html
This document gives you the background and show the steps for implementing an L2TP/IPsec based VPN using Linux, Windows and MacOSX |
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Configuring an IPsec tunnel between Openswan and Windows - http://www.natecarlson.com/linux/ipsec-x509.php
This document gives you the details how to setup a virtual private network between Linux/Openswan on one side and Microsoft Windows 2000 and XP on the other side. |
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German book covering Linux VPNs - http://www.opensource-training.de/buecher_new.php
This site offers a German book (pdf) covering Linux VPNs for download. |
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OpenVPN using X.509 certificates - http://www.onlamp.com/pub/a/security/2004/10/21/vpns_and_pki.html
This document explains how to deploy a VPN using OpenVPN and OpenSSL. |
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An Intro To SSL VPN - http://www.hostlibrary.com/node/view/148
An article discusses the types of VPN available, benefits, and considerations necessary when deploying SSL VPNs. |