I started this project because I was using a number of IPIP tunnels to connect a number of private networks over the Internet, and I needed encryption for a few resons. Above all I wanted to be able to use standard protocols such as FTP and NFS without having to worry about cleartext passwords and snooping.

I knew that I needed IPsec, and the only free implementation under active development I could find for Linux was FreeSWAN, but looking closer it seemed too much for my simple case. My first impression was that it was hard to understand and hard to configure, especially for the simple case of manually configured tunnels with fixed keys. Routing was also strange. I wanted something resembling the standard IPIP tunnel, but when I could not find it, I printed out the IPsec RFCs and started reading, and after that I started coding.

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