Published by Alisha McKerron
In my last article,”What makes it possible for us to have a web activity profile and how can we guard against it?”, we learnt that third party cookies enable our internet browsing to be tracked and that there are various ways we can block them. However there are other methods of tracking that can be used — for example, using browser fingerprinting techniques.
What are browser fingerprinting techniques?
Just like our unique fingerprints can be used to identify us, so can a set of data related to our device — from the hardware to the operating system, to the browser and its configuration — be used to identify us. We may be surprised if not dismissive that such information has any value since the devices and software we use are pretty common. But, consider that everytime we visit a webpage our browser is communicating with the server hosting that page; consider the variable content (text, pictures, logos, live feeds etc.) of each webpage and the settings on our computer and hardware needed to render a webpage, and consider that combining all of this information into one set of data can be used to create reasonably effective identifiers. Adding more data to the mix can be used to identify increasingly more specific groups of users: for example, while 10 people may share the same browser, only 5 might share the same browser and operating system, only 3 share the same browser, operating system, and screen size, … and so on, and so forth, until ideally there’s enough data to uniquely identify one user, because nobody else shares the same device, or browser-specific attributes.
Examples of this kind of data include plug-ins, time zone, screen size, system fonts, if cookies are enabled, language, ad blocker used, device memory, type of browser (i.e. Mozilla, Chrome, Safari etc.), screen size, screen orientation and display aspect ratio etc.
Unintended consequences of browser fingerprinting
Uses of fingerprint data
Like cookies, while the result of browser fingerprinting benefits us — for example improving security, allowing us to receive services that are useful to us etc.— it is a power for good. But it benefits third parties too— such as the advertising industry with a 2020 Q2 global digital ad spend of $614 billion. Since it does so without our knowledge and at our expense, it is a serious threat to our online privacy. How can we protect ourselves against browser fingerprinting?
Protecting ourselves from browser fingerprinting