Implementing Site-to-Site IPSec Between a Cisco Router and Linux FreeS/WAN

This paper begins by providing a brief overview of IPSec. It then discusses the major features, differences, and issues surrounding Cisco's IOS IPSec offering versus the FreeS/WAN offering. Finally, it describes an example implementation and step-by-step procedure that can be used to set up an IPSec site-to-site VPN between a Cisco 2621 IPSec-enabled router and an Intel Architecture-based computer running Linux with the FreeS/WAN 1.9 IPSec implementation.