References
1.Building Linux Virtual Private Networks
Oleq Kolesnikov and
Brian Hatch, 1st Edition, Feb. 4, 2002
2.FreeSWAN Online Documentation
www.freeswan.org
3.Setting up a VPN Gateway
Linux Journal, January 2002, Issue
93
4.Administering Linux IPSec VPN
Sys Admin, March 2002,
Volume 11, Number 3
5.Lesson 165: IP VPN Services
Network Magazine April
2002, Vol.17, No.4