I went to London today and on the way I read my favourite magazine, Scientific American. The issue I was reading was a special issue focussing on privacy in the modern world (September 2008).

I have a profile on Facebook and, heck, a website here where I occasionally say something that I feel needs saying (less frequently recently). I also use Google to search and only rarely delete anything from my search history. But the article I was reading that triggered the ‘must write’ response was one on RFID tags.

When I first decided to get an Oyster card it was after a long period of thinking about it. To me having the Mayor of London able to see where I’m going seemed like a bit of an imposition. Why should he need to know where I’m going? And can I trust a man who leaves the Congestion Charge cameras on on Sundays? Eventually I decided that as it was voluntary it wasn’t unreasonable to help them manage the network and, anyway, it’s cheaper for the right reasons.

But as I read the RFID article I realised how many things I was carrying had an RFID tag in them. I was going to an examination so I had my new-style passport with me as ID. This contains a passive chip that is encrypted (I believe) using my passport number as a key. But also on my person I had said Oyster card and also my new Barclaycard that has PayPass.

If I wander into a shopping centre, the article explained, an array of RFID tag readers in appropriate places may just be able to read my RFID tags and find out where I go, where I stop or dally and where I don’t go. While, at the moment, this would not necessarily identify me as me, it wouldn’t be too hard for that to happen and it would be much easier to integrate that data into a useful database than are images on CCTV.

I have to admit, despite my concerns about freedom I am not worried about the implementation of RFID in the West yet (China’s another matter: China to issue RFID ID cards) but it is an area we need to keep an eye on.