Identification of visitors crucial to most web sites, either to provide content or track miscreants. The most common mechanism to track users is a simple cookie file. As browsers have evolved many have made tracking with this method problematic (e.g. by activating the “incognito” mode in web browsers). Cookies also fail to identify a user who uses several different web browsers on the same device. This led to the development of the device fingerprint — a unique user identifier which does not change between successive sessions and which does not depend on the selected web browser.
A device fingerprint is known by many names including a machine fingerprint, browser fingerprint, device print, user fingerprint and others. It is composed of information collected about an online computing device for the purpose of unique identification of the device on subsequent visits. A device fingerprint can fully or partially identify individual users or devices even when cookies and other tracking data is turned off.
Basic web browser information has long been collected by web analytics services in an effort to accurately measure real human web traffic and discount various forms of click fraud. With the assistance of client-side scripting languages, the collection of much more esoteric parameters is possible. Device fingerprints have proven useful in the detection and prevention of online identity theft and credit card fraud.
The Darkwave Technologies device fingerprint project was created to develop highly reliable code to make it simpler for developers to create a device fingerprint system for use in online fraud prevention and the prevention of general malicious behavior.