There are two classes of contraband at airport security checkpoints: the class that will get you in trouble if you try to bring it on an airplane, and the class that will cheerily be taken away from you if you try to bring it on an airplane. This difference is important: Making security screeners confiscate anything from that second class is a waste of time. All it does is harm innocents; it doesn't stop terrorists at all.

Let me explain. If you're caught at airport security with a bomb or a gun, the screeners aren't just going to take it away from you. They're going to call the police, and you're going to be stuck for a few hours answering a lot of awkward questions. You may be arrested, and you'll almost certainly miss your flight. At best, you're going to have a very unpleasant day.

This is why articles about how screeners don't catch every -- or even a majority -- of guns and bombs that go through the checkpoints don't bother me. The screeners don't have to be perfect; they just have to be good enough. No terrorist is going to base his plot on getting a gun through airport security if there's decent chance of getting caught, because the consequences of getting caught are too great.

Contrast that with a terrorist plot that requires a 12-ounce bottle of liquid. There's no evidence that the London liquid bombers actually had a workable plot, but assume for the moment they did. If some copycat terrorists try to bring their liquid bomb through airport security and the screeners catch them -- like they caught me with my bottle of pasta sauce -- the terrorists can simply try again. They can try again and again. They can keep trying until they succeed. Because there are no consequences to trying and failing, the screeners have to be 100 percent effective. Even if they slip up one in a hundred times, the plot can succeed.

The same is true for knitting needles, pocketknives, scissors, corkscrews, cigarette lighters and whatever else the airport screeners are confiscating this week. If there's no consequence to getting caught with it, then confiscating it only hurts innocent people. At best, it mildly annoys the terrorists.

To fix this, airport security has to make a choice. If something is dangerous, treat it as dangerous and treat anyone who tries to bring it on as potentially dangerous. If it's not dangerous, then stop trying to keep it off airplanes. Trying to have it both ways just distracts the screeners from actually making us safer.

There are two classes of contraband at airport security checkpoints: the class that will get you in trouble if you try to bring it on an airplane, and the class that will cheerily be taken away from you if you try to bring it on an airplane. This difference is important: Making security screeners confiscate anything from that second class is a waste of time. All it does is harm innocents; it doesn't stop terrorists at all.

Let me explain. If you're caught at airport security with a bomb or a gun, the screeners aren't just going to take it away from you. They're going to call the police, and you're going to be stuck for a few hours answering a lot of awkward questions. You may be arrested, and you'll almost certainly miss your flight. At best, you're going to have a very unpleasant day.

This is why articles about how screeners don't catch every -- or even a majority -- of guns and bombs that go through the checkpoints don't bother me. The screeners don't have to be perfect; they just have to be good enough. No terrorist is going to base his plot on getting a gun through airport security if there's decent chance of getting caught, because the consequences of getting caught are too great.

Contrast that with a terrorist plot that requires a 12-ounce bottle of liquid. There's no evidence that the London liquid bombers actually had a workable plot, but assume for the moment they did. If some copycat terrorists try to bring their liquid bomb through airport security and the screeners catch them -- like they caught me with my bottle of pasta sauce -- the terrorists can simply try again. They can try again and again. They can keep trying until they succeed. Because there are no consequences to trying and failing, the screeners have to be 100 percent effective. Even if they slip up one in a hundred times, the plot can succeed.

The same is true for knitting needles, pocketknives, scissors, corkscrews, cigarette lighters and whatever else the airport screeners are confiscating this week. If there's no consequence to getting caught with it, then confiscating it only hurts innocent people. At best, it mildly annoys the terrorists.

To fix this, airport security has to make a choice. If something is dangerous, treat it as dangerous and treat anyone who tries to bring it on as potentially dangerous. If it's not dangerous, then stop trying to keep it off airplanes. Trying to have it both ways just distracts the screeners from actually making us safer.

---

Bruce Schneier is chief security technology officer of BT. His new book is Schneier on Security.

As we get closer to the conference dates, I wish that I had made plans to fly back to the US to meet everyone.    However, I have been cutting back on public speaking, taking a break since May.  In addition, Gartner did not ask me to speak at their Event Processing Summit this year, I assume because they did not want to pay airfare for my flight from Thailand to the US.    Also, Gartner always likes to fill their conference speaking slots with as many Gartner speakers as they can, unless you are a paid sponsor; and I noticed a number of Gartner employees speaking in multiple slots.

(Editorial Note) Then again, maybe I complained to much about the lack of organization and conference problems when I was invited at be a Gartner keynote speaker last time - reservations not made propertly,  problems with the guest speaker registration list at sign-in, rooms shifted without notifying the speakers and panelists.   Admittedly, I was not happy with the conference organizers at the last get together.  This was my fault, as I am accustomed to better conference execution and am probally too “picky” about details these days - my bad.  Anyway, the Gartner organizers apologized numerous times, saying they had too many conferences going on at the same time and not enough people to cover them all.

One of the problems with spending so much time in Asia, especially in Thailand, is that guest speakers are really treated as VIPs.  There are usually special comfy couches set up for the speakers and the conference staff really treat you very nice, taking care of you every step of the way.   In fact, there is an entire very nice culture around how guest speakers are treated in Thailand.   Often, they pin flowers on the VIP speakers and take your photos like you are a star.    Very nice culture.

I absolutely look forward to speaking on event processing or CEP at a future venue and meeting everyone face-to-face instead of over the net.  My sincere and deepest apologies for not attending either the Gartner or the EPTS event this year.   

PS:  If you take up a collection and send me a RT business class air ticket, I might change my mind

Parlez-vous open source? While wide-spread open source usage is still debated in many companies, the French have been advocating for all open source all the time in government and education. French President Nicolas Sarkozy set up an economic commission that recommended tax benefits to stimulate more open source development. Lesson learned from France: start ‘em early. “All students in France use open source.”

Just in time for Labor Day, John Edwards (no, not that one) comes out with an informative guide on “Who provides what in the cloud”. No doubt, this will be a rapidly expanding list, but what’s really interesting is the comment on the article. People have very strong opinions on the cloud…

Research firm Aberdeen Group reports that network costs will increase slightly more than 5 percent over 2007. Contributing factors: “need for speed”, shift from standard to mobile PCs (more end points of connectivity), and the ever-expanding network. And of course the hidden costs of multiple tools with multiple management consoles – if you’re not smart enough to choose say a comprehensive network management solution that is vendor agnostic…One tool to monitor them all…

And just because I miss the Olympics already, here’s an irreverent take on what it’s like to lose to Michael Phelps. http://www.thetechstop.net/?p=1503

Enjoy your long Labor Day Weekend!