The prerequisites for connecting to VLAN are broken apart in generic prerequisites, and OS specific prerequisites.
A x.509 certificate, preferably signed by the VLAN Certificate Authority.
An assigned subnet in the 10.64.0.0/14 range
This document describes connecting two different Linux IPSec implementations:
Linux kernel 2.4.x
(Super) FreeS/Wan
and:
Linux kernel 2.6.x
ipsec-tools or -
FreeS/Wan frontend
For all of the above, the rest of the requirements are:
IPRoute2
Zebra/Quagga
OpenSSL
racoon
Zebra/Quagga
OpenSSL
Windows 2000 (Professional, (Advanced) Server), Windows XP Professional or Windows 2003 Server
Patience, coffee and a RSI free mousehand