Why Device Fingerprinting Matters

How it Works: Every time a computer, cellphone, or other device connects to the Internet, it broadcasts information about its properties and settings, such as which browser and version it’s running, its screen resolution, clock settings, and many more. Those individual pieces of information can be combined to build unique profiles — or fingerprints — that can be tracked as they move across the Web. Unlike cookies, fingerprints cannot be deleted as they identify devices themselves, rather than pieces of data placed on them. Even if some of their characteristics change, fingerprints will usually capture enough data points to still successfully recognise a device, and will simply update the print with the new information. A print can, in theory, remain intact for the life of a device. Providers of the technology claim it can identify unique devices with upwards of 90 percent accuracy.

Who is Doing it: Fingerprinting is still new. Mobile ad network InMobi is currently in the process of implementing fingerprinting across its network powered by 41st Parameter, for example. Other companies such as BlueCava and Iovation provide similar technologies. Ad networks, ad servers, media buyers, publishers, agencies, DSPs, data providers and more can use the technology, although few publicly acknowledge doing so. (BlueCava, for example, will not disclose any of its clients.)

Why it Matters: Cookies are central to online advertising but there’s no equivalent for cellphones and tablets. Mobile apps, for example, don’t allow the placement of cookies, and mobile Web browsers all deal with them in different ways. Fingerprints can be used as an alternative to cookies to help identify, target, and track devices and their users, and to deliver ads and content based on that information. Its uses aren’t limited to mobile devices, though. In theory, any connected device has the potential to be fingerprinted, including games consoles, TVs, and even cars. The technology can also be used to establish relationships between multiple pieces of hardware, thanks to its persistence. A user’s behavior could therefore be tracked across their laptop, cellphone, and tablet, and tied together to create a central pool of behavioural data, for example. That naturally brings up serious privacy questions, and it could explain the reticence of many companies to to trumpet using it.

Assessment: Device fingerprinting has the potential to emerge as the non-desktop equivalent of the cookie, and could help solve many of the measurement, tracking, and targeting problems currently associated with mobile and tablet advertising. Furthermore, it could even become the de-facto standard for all digital tracking — thanks to its cross-platform capabilities — and provide a single technology for identifying users across all digital channels. That is, of course, if privacy concerns around the practice don’t hinder its progress. The experience of so-called flash cookies, which cannot be deleted, has proven that advancements in tracking methods inevitably brings a sharp pushback. Even more problematic is how a consumer even knows if he is being targeted in this method. All the fingerprinting providers offer opt-outs on their sites, but it’s hard to imagine any significant number of people even knows the practice is being used.