A few points of note: it's rather weird to call BLACKER a "VPN"; it's likely much broader than this (it's a network, crypto suite, secure kernel, system architecture, etc), and yet encompasses a very different goal. In fact, the degree to which it originates out of secure kernel research is, we argue in our paper, somewhat unclear, and perhaps this is only a small part of the equation.
If anyone has any additional information about these early architectures, I would love to speak with you, contact me at http://iqdupont.com.
