- [CIPE](http://cipe-linux.sourceforge.net/)
- [CloudVPN](http://dev.e-x-a.org/projects/cloudvpn/wiki)
- [FairVPN](http://minerva.netgroup.uniroma2.it/fairvpn)
-- [FreeS/WAN](http://www.freeswan.org/)
- [GVPE](http://software.schmorp.de/pkg/gvpe.html)
- [l2tpd](http://sourceforge.net/projects/l2tpd)
- [Nest](http://www.targeted.org/nest/)
- [Poptop](http://poptop.sourceforge.net/)
- [QuickTun](http://wiki.qontrol.nl/QuickTun)
- [SocialVPN](http://socialvpn.wordpress.com/)
+- [strongSwan](http://www.strongswan.org/)
- [VPMN](http://code.google.com/p/vpmn/)
- [vpnd](http://vpnd.linuxsys.com/)
- [VTun](http://vtun.sourceforge.net/)