Add to IPsec the fact that it was cryptography developed under US export restrictions. This is probably the reason why it has AH for data integrity and ESP for

Add to IPsec the fact that it was cryptography developed under US export restrictions. This is probably the reason why it has AH for data integrity and ESP for data protection and/or, well, integrity, rendering AH actually excessive. > Until now, OpenVPN has prevailed. Which is somewhat funny, as FreeS/WAN derivatives are much more convenient to configure than OpenVPN with its tons of options that you need to put either on server side or client side (and those differ greatly) and routing that is very, very easy to screw up. Also, I always say that OpenVPN is a weird case of a program open source from the ground up that has a closed communication protocol. No specification and extracting the protocol from the source is difficult in this case.