Update 11/26/2011: I’ve had two excellent responses to my challenge. You can see them all on this page.

A couple of people have asked me about the symbols that I use to illustrate protocol diagrams. Let me first say that I claim no particular credit or blame for this style; all of that goes to Thomas Ptacek.

These symbols are part of the AIGA Symbol Signs package, a collection of freely downloadable stencils for the standard international symbols. They’re wonderful for someone as graphically challenged as I am. You can download a stencil set for Omnigraffle, or get the EPS templates from the AIGA site.

As Thomas points out, there’s all kinds of useful security stuff in them: the international symbols for Alice and Bob, the passport agent and keys, and some less-useful things like pictures of ships and planes. (Though even these turned out to be useful once, when I reviewed a security system for a cruise ship.)

However, I think what prompts questions is not Symbol Signs, but rather, it’s the symbol I’ve been using to represent the adversary. Some people seem to think the baby is an odd choice. (My guess is that these people simply don’t have one.)

However you feel about my choices, I think we can all agree that there’s a tremendous need for better design style in scientific presentations. It’s 2011, and Comic Sans + Microsoft clip art no longer cuts the mustard.

Announcing a contest. In order to do my small part to improve the appearance of security presentations, and to resolve this baby-as-adversary issue, I have decided to offer a whopping $200 (plus fame and glory) to any artist, or person of artistic bent, who can come up with a better AIGA-style symbol for the adversary, and/or other security-related symbols if they’re exceptional. This is a one-time prize, and will be offered to a single winner of my choice. I realize this isn’t a whole ton of money, but if I like the result I promise I’ll do my level best to praise your talents far and wide.