Security expert Bruce Schneier writes an op-ed for the Wall Street Journal explaining why technology will not prevent identity theft.
Impersonation isn’t new. In 1556, a Frenchman was executed for impersonating Martin Guerre and this week hackers impersonated Barack Obama on Twitter. It’s not even unique to humans: mockingbirds, Viceroy butterflies, and the brown octopus all use impersonation as a survival strategy. For people, detecting impersonation is a hard problem for three reasons: we need to verify the identity of people we don’t know, we interact with people through “narrow” communications channels like the telephone and Internet, and we want computerized systems to do the verification for us.
Traditional impersonation involves people fooling people. It’s still done today: impersonating garbage men to collect tips, impersonating parking lot attendants to collect fees, or impersonating the French president to fool Sarah Palin. Impersonating people like policemen, security guards, and meter readers is a common criminal tactic.
These tricks work because we all regularly interact with people we don’t know. No one could successfully impersonate your brother, your best friend, or your boss, because you know them intimately. But a policeman or a parking lot attendant? That’s just someone with a badge or a uniform. But badges and ID cards only help if you know how to verify one. Do you know what a valid police ID looks like? Or how to tell a real telephone repairman’s badge from a forged one? […]
These days, a lot of identity verification happens with computers. Computers are fast at computation but not very good at judgment, and can be tricked. So people can fool speed cameras by taping a fake license plate over the real one, fingerprint readers with a piece of tape, or automatic face scanners with — and I’m not making this up — a photograph of a face held in front of their own. Even the most bored policeman wouldn’t fall for any of those tricks. […]
We can reduce the risk of impersonation, but it will always be with us; technology cannot “solve” it in any absolute sense. Like any security, the trick is to balance the trade-offs.