I am working on a solution for security in my house based on an IPSec tunnel. This is partially based on a NSA capability package document re using commercial off-the-shelf encryption techniques for separation of security domains. The idea was interesting enough to try and replicate as part of my home VPN interconnections.
I have been reviewing a number of different posts to get this working, see here, here, and here. Internet Protocol Security (IPsec) is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session. The major contender package is StrongSwan rather than OpenVPN which does not support IPSec.