FreeS/WAN, for Free Secure Wide-Area Networking, was a free software project, which implemented a reference version of the IPsec network security layer for Linux. The project goal of ubiquitous opportunistic encryption of Internet traffic was not realized, although it did contribute to general Internet encryption.
The project was founded by John Gilmore, and administered for most of its duration by Hugh Daniel. John Ioannidis and Angelos Keromytis started the codebase while outside the United States of America prior to autumn 1997. Technical lead for the project was Henry Spencer, and later Michael Richardson. The IKE keying daemon (pluto) was maintained by D. Hugh Redelmeier while the IPsec kernel module (KLIPS) was maintained by Richard Guy Briggs. Sandy Harris was the main documentation person for most of the project, later Claudia Schmeing.