VPN labs - research community
- VPN labs is an open community for researching, reviewing, and discussing Virtual Private Networks.
- http://www.vpnlabs.org/

Tom Dunigan's Virtual Private Networks page
- This page describes IP-based VPN technology over the Internet
- http://www.csm.ornl.gov/~dunigan/vpn.html

NW Fusion: Research: VPNs
- This is a comprehensive collection of VPN resources and articles.
- http://www.nwfusion.com/topics/vpns.html

Find VPN
- Directory of VPN providers, articles, and links.
- http://www.findvpn.com

Corecom VPN FAQ Page
- Geared towards those new to VPN.
- http://www.corecom.com/external/vpn/vpnfaq.htm

About.com VPN directory
- A smattering of VPN resources including a glossary and a self-test.
- http://compnetworking.about.com/cs/vpn/index.htm

How Stuff Works: How Virtual Private Networks Work
- Gives definition of VPN and an overview of general VPN topics, includes diagrams and an animation.
- http://www.howstuffworks.com/vpn.htm

Virtual Private Network Consortium
- VPNC is the international trade association for manufacturers in the VPN market.
- http://www.vpnc.org/