Shrew Soft VPN Client

"This application is an advanced IPSEC Client for Win32"
Windows Platforms

The Shrew Soft VPN Client for Windows is a free IPsec Remote Access VPN Client for Windows 2000, XP, Vista and 7 operating systems ( x86 and amd64 versions ). It was originally developed to provide secure communications between mobile Windows hosts and open source VPN gateways that utilize standards compliant software such as ipsec-tools, OpenSWAN, FreeSWAN, StrongSWAN, isakmpd. It now offers many of the advanced features only found in expensive commercial software solutions and provides compatibility for VPN appliances produced by vendors such as Cisco, Juniper, Checkpoint, Fortinet, Netgear, Linksys, Zywall and many others.

Linux and BSD Platforms

The Shrew Soft VPN Client for Unix is a free IPsec Client for FreeBSD, NetBSD and Linux based operating systems. This version is distributed under an OSI approved open source license and is hosted in a public subversion repository. It supports most of the features availalble in the Windows VPN Client version with the exception of those which are not cross platform compatible.