The Craft of System Security

The Take-Home Lesson

Crafting a secure system is hard. Many factors contribute to this problem.

• The artisan must look at the entire system, including many levels of hardware and software technology, user interface design, manufacturing, sales, maintenance—as well as laws, standards, social practices, psychology (and probably a few other things we're missing).
• The components and application of this system continue to undergo revolutionary changes. Would you walk over a bridge built 30 years ago? (Of course!) But would you trust a cryptosystem designed 30 years ago? Would you hook up a PC, whose last patch was only 10 months ago, to the Internet?
• The science and engineering behind bridge building are well understood. In contrast, "security" is ...