Speaker Bruce Schneier
Time 2008-01-30 09:00
Conference LCA2008


About the author:


  • Feeling. I feel secure.
  • Reality. I am actual secure.

You can feel secure, but not actually be secure.
You can be secure, but not feel secure.

Economics of security. Security measures that make no sense on a technical view make perfect sense on an economic view.

economics - trade offs

  • money
  • time
  • feature set
  • security

security consumers

Not “does this thing make me more secure?”, but “is it worth it?”

None of the audience wear bullet proof vest, not worth

  • money
  • fashion

Rabbit eating grass, and sees fox. “Should I stay I should I flee?” Bad choice: starve; good choice: survive and reproduce.

Humans respond to feel of security threat rather then reality.

Unknown risks seem more of threat then known risks, eg:

  • flying, seems riskier then driving
  • kidnapping via stranger seems risky, but reality is kidnapping by known person is more likely.

Feeling vs Reality get out of whack.

  • Reality low feeling high; false sense of security
  • Reality high feeling low; irrational, paranoia.

CIA, ignore feeling, fix reality.

economics, cost vs benefits.

  • cost of security failures
  • regulations, cost of non-compliance
  • loss of customers


  • cost of security
  • cost of convenience
  • less features
  • less profits

People make trade off based on feeling, not the reality. Companies want to make people feel secure, ignore reality; snake oil; hope people don’t notice.

Alternative, make people actually secure, and hope they actually notice.

Sometimes people do notice, e.g. new door lock doesn’t work if attacks increase for this particular type of door lock.

Security is very emotional. Need to learn from the information.

Poor understanding of risks, costs, counter-measure and how it works. People with specific agendas will add to the confusion. Industry may push for security measures even though there is data available that they are not very effective.

How do we know if sky marshals stopped terrorists after 911? There is no data. Makes it harder to reconcile feeling and reality.

Markets with asymmetric ratio between knowledge of buyer vs seller, e.g: buying a call, seller knows more about the car then the buyer.

Suppose 100 cars for sale

  • 50 good $100
  • 50 lemons $100

More lemons get sold because the consumer cannot tell the difference.

IT - firewall market; the winners weren’t the best ones. Compare two routers. One is better designed, one in thrown together; buyer can’t tell the difference, and will buy the cheaper one, push the good one out of the market.

Used car sales, warranty is the deciding factor.

Computers, reputation of company, certifications, recommendations, open source, closed source, are factors used to decide a better product.

Sometimes signals can go either way, eg. some people think open source is more secure, others think closed source is more secure.

Signals can be manipulated.

Security decisions outsourced, eg. to government, who will manipulate signals to their benefit.



Business world: if enough information, merge gap between feeling and reality. Calculate risk of getting whacked (e.g. store robbed), and spend that amount on security.

Event probability: 0 Number of times of getting hit: infinity

0 * infinity = any number you want

Individuals, too much feeling, too much fear.

Fear is very basic. Our fear organ in our brain, base of brain, how we feel fear. Increases heart rate, muscle tension, etc. Faster then consciousness.

We get to override our fear, eg. attack instead of run away. Or stand up for boss instead of leaving.

If you feel fear, I will make you better, by feeling less fear.

Both fear and reality of security are both important. Problem is when both diverge.

Example 1: 1980s, non-prescription drug poisoning, random person would take poisoned drug and die. Entire USA population scarred of buying drugs. Solution: tamper proof lid. Saved the entire industry. Non-effectual security solution, easy to bypass, eg. syringe.

Example 2: Babies in maternal hospital are given tags, so prevent baby theft. Address feeling rather then reality of baby getting stolen.

Both feeling and reality both important.


How do you separate feeling and reality in airline security?

Visible security personal, carrying rifles without bullets. That addresses the feeling of security.

They address the threats we know about, shoe bombings, liquid bombs, hit the press, so these are threats the address. Address the feeling, not the reality.

TSA less trusted then taxation department.

In five years, no change expected. In 10-20 years, things might change.

Measuring security

Isn’t always hard to measure, can measure crime rate around the university campus.

In IT, there is no hard data on crime rate.

  • people don’t report
  • people don’t know they have been attacked

Antidote for product endorsement

Security cameras. Very emotional propaganda. Giving it away from camera companies. “Cameras - I feel safer”

RFID cards, make people feel safer.

I don’t endorse anything, I don’t have time to research and evaluate, ensure it is reliable and secure.

Maternity ward

Feel safe because of RFID tag. How do you stop stupid stuff? Write and speak: the emperor has not clothes.

where it is possible: information is the solution. Get people to get beyond their fears.

Producers of Software

Expensive process to make feeling and reality converge?

We know very little about software security.

Lots of good books on writing secure software.

In absence of theory, all you can do is put a lot of effort to make it more secure.

Pull buffer overflows out of language.

No rigorous methodology.

Degree of laziness

Most people don’t want to jump through hoops to be safe.

Even in aircraft design, eg. connecting navigation and entertainment systems due to laziness.

Just information may not make things better.

It is a lemon market.

People are commonly lazy, because they don’t have the expertise. It is not there area, and not what the understand. It is not possible to seek expert, because experts will have there own agendas on both sides.

Distance between feeling and reality

The more distance between feeling and reality, the more noise gets injected.

No solution, we are stuck with this as a species.

Only answer, a sloppy answer, doesn’t work well: Information.

Technology vs Security

Will technology mean decreased security, privacy, etc?

Digital aspects of security, much more important then physical security.

Partly because we live in a peaceful society. We don’t worry so much about physical security.