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Bruce Schneier is the chief security technology officer at BT and a celebrated writer and speaker on privacy, cryptography and security issues.
Welcome to the future, where everything about you is saved. A future where your actions are recorded, your movements are tracked, and your conversations are no longer ephemeral. A future brought to you not by some 1984-like dystopia, but by the natural tendencies of computers to produce data.
Data is the pollution of the information age. It’s a natural by-product of every computer-mediated interaction. It stays around forever, unless it’s disposed of. It is valuable when reused, but it must be done carefully. Otherwise, its after-effects are toxic.
And just as 100 years ago people ignored pollution in our rush to build the Industrial Age, today we’re ignoring data in our rush to build the Information Age.
Increasingly, you leave a trail of digital footprints throughout your day. Once you walked into a bookstore and bought a book with cash. Now you visit Amazon, and all of your browsing and purchases are recorded. You used to buy a train ticket with coins; now your electronic fare card is tied to your bank account. Your store affinity cards give you discounts; merchants use the data on them to reveal detailed purchasing patterns.
Data about you is collected when you make a phone call, send an e-mail message, use a credit card, or visit a website. A national ID card will only exacerbate this.
More computerised systems are watching you. Cameras are ubiquitous in some cities, and eventually face recognition technology will be able to identify individuals. Automatic licence plate scanners track vehicles in parking lots and cities. Colour printers, digital cameras, and some photocopy machines have embedded identification codes. Aerial surveillance is used by cities to find building permit violators and by marketers to learn about home and garden size.
As RFID chips become more common, they’ll be tracked, too. Already you can be followed by your cellphone, even if you never make a call. This is wholesale surveillance; not “follow that car,” but “follow every car”.
Computers are mediating conversation as well. Face-to-face conversations are ephemeral. Years ago, telephone companies might have known who you called and how long you talked, but not what you said. Today you chat in e-mail, by text message, and on social networking sites. You blog and you Twitter. These conversations – with family, friends, and colleagues – can be recorded and stored.
