[quinndupont]

Neither article makes any mention of Perl, which isn't terribly surprising, since BLACKER is still highly classified, with very little is publicly known about its design and operation. You'll find some discussion of BLACKER in my recent article: http://ieeexplore.ieee.org/document/7763734/ (Open access/free pre-print version: http://iqdupont.com/assets/documents/DUPONT_FIDLER-2016-Prep...)

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.

[nickpsecurity]

It was here thanks to acqq:

http://cahighways.org/wordpress/?p=5460

Yeah, BLACKER did quite a bit. It was a network MLS component like many others that came after it. GEMSOS, Boeing SNS Server, and DiamondTek LAN are examples. Modern variant would be an Octeon 2 or 3 PCI card with similarly secure software.

Too much to explain, though. BLACKER's main purpose was securing the connection between dumb terminals and things they connected to. It used crypto, MLS, and TEMPEST-style hardware. It was a network device as well. A VPN is closest term for modern audience to convey its main goals.