The end of anonymity
Thanks to the internet, there is no such thing as anonymity.
So says Dr Ari Juels, the chief scientist of RSA, the security vendor behind the world's biggest security conference.
If you think about all the digital crumbs we leave all over cyberspace, Dr Juels's assertion is not that hard to understand.
He claims that it takes a mere 10 digits of information to label uniquely each human being on the planet. It is not a new theory of his, but it is certainly one that is gaining more resonance as we grow more accustomed to parting with the smallest of details about our personal life.
"We are spewing information out in ways that we are not fully aware of and so those 10 digits tend to be collectable in many different circumstances and our identities will be very easy to unmask, at least on a technical level," Dr Juels told the BBC.
He said we leave these little tell-tale snippets all around the place - from websites that can pinpoint our geographical location, what kind of computer and browsers we are using to the things we carry in our handbag that act like mini-tracking devices.
Small wireless microchips - often called radio frequency identification, or RFID, tags - are in car keys, credit cards, passports, building entrance badges, and transit passes. They emit unique serial numbers and they can be traced back, of course, to us.
One of the biggest bull's-eyes we carry is our cellphone with its GPS tracking and our willingness to sign up for location-based services while on the go.
Dr Juels pointed out the very obvious fact that we are surrounded by video surveillance cameras and as today's face recognition software becomes more sophisticated, it is unlikely anyone of us will remain merely a face in the crowd.
"My proposition, from a technical perspective, is that anonymity is a losing battle. We have to give up on the idea that we can remain anonymous," said Dr Juels.
As part of an experiment to find out how useful the digital crumbs we leave lying around are, Dr Hugh Thompson, a renowned security expert who teaches computer security at Columbia University set his students an interesting task.
"The homework assignment I set students was to go out and find information that can be found publicly, like hirings and firings and put together a narrative that helps track down a real person."
He said one student concentrated on a person who sent out a tweet that said "major stuff is happening in our quality control department. The project manager is firing folks like it's hunting season."
Dr Thompson said the trail led the student from the Twitter account to a personal website and from there to a hint about working in Mubai for a major retailer to eventually tracking down the person, their workplace and a phone number for them.
Dr Thompson calls this "gateway data".
"This is data that may not appear to have any value or importance but when used in combination with other information, it reveals something very sensitive about the company or individual."
He advocates better education, but not a simple list of "do"s and "don't"s.
"Companies need to educate about the risk. Go and show these narratives. Pseudo-stalk yourself and build a narrative for yourself. People learn by example. If they can see the damage they might cause, they will change their behaviour," suggested Dr Thompson.
He also noted that "the longer history of data that we have online, the more information we can mine and the more we can find out about a person or company."
Dr Thompson said that developers, social networking sites and institutions have to help people make better decisions.
"There are some good risk-choices people make naturally. If you are walking down the street in New York and you see the street light is out and there is graffiti everywhere, you might hear a gun shot - these are signs that we have come to learn and accept that 'wow I really need to get out of this neighbourhood'. Online, we need to build that same intuitiveness for users. In the cyber-world, we don't have it yet."
Dr Juels said he believed we cannot afford to ignore the signs.
"Technology shifts 20 years from now means we are going to have a very different notion of what privacy and anonymity means. It would be nice to make informed decisions now and be conscious of the forms of erosion that are taking place."