Chapter 23
Involving Experts

There is something strange about cryptography: everybody thinks they know enough about it to design and build their own system. We never ask a second-year physics student to design a nuclear power plant. We wouldn't let a trainee nurse who claims to have found a revolutionary method for heart surgery operate on us. Yet people who have read a book or two think they can design their own cryptographic system. Worse still, they are sometimes able to convince management, venture capitalists, and even some customers that their design is the neatest thing since sliced bread.

Among cryptographers, Bruce's first book, Applied Cryptography [111, 112], is both famous and notorious. It is famous for bringing cryptography to the attention of tens of thousands of people. It is notorious for the systems that these people then designed and implemented on their own.

A recent example is 802.11, the wireless network standard. The initial design included a secure channel...