How to setup IPSec effectively on LAN so that I can securely use from a machine of different external network.
Whats the significance of xl2tpd.
I see that IPSec is faster than OpenVPN.
Also I would like to know if something like Hotspot Shield can be implemented LAN, where they assign a different IP address on after establishing secure VPN.
** I see the fact that HotSpot Shield Server are located in USA.
**IPSec is a kernel implementation while OpenVPN is a userspace implementation
You have three separate questions here - Ask Ubuntu works best on single question and answers.
I recommend you have a read through the Man Page for ipsec. It should give you a good overview of the package and how it works.
I have no experience on setting up what you want to achieve but I was able to find this guide to set it up on 10.04, it still should be fairly relevant to 11.04 though. It details xl2tpd Since Windows default client is more than just IPSec, it uses L2TP inside of an IPSec SA, you need a daemon to handle that which is what xl2tpd will do.
As for Hotspot Shield have a read through a previous question for information on it and details on other options.
