Trusted insiders and how to protect against them

From Bruce Schneier’s “Basketball Referees and Single Points of Failure” (Crypto-Gram: 15 September 2007):

What sorts of systems — IT, financial, NBA games, or whatever — are most at risk of being manipulated? The ones where the smallest change can have the greatest impact, and the ones where trusted insiders can make that change.

It’s not just that basketball referees are single points of failure, it’s that they’re both trusted insiders and single points of catastrophic failure.

All systems have trusted insiders. All systems have catastrophic points of failure. The key is recognizing them, and building monitoring and audit systems to secure them.