When you use services from the Internet, you leave behind a so-called digital fingerprint. This fingerprint makes it possible to identify you and, if necessary, to recognize you when you use a service again. The methods used for this are the Internet protocol, various forms of cookies, the historical data in browsers or so-called canvas fingerprinting.
IP addresses offer a simple technical method for recognizing users. Communication on the Internet is essentially based on the Internet Protocol (IPv4, IPv6). Therefore, computers, such as web servers or your own device, are assigned a so-called IP address. Memorizing an IP address is not easy. Therefore, the Domain Name System (DNS) associates IP addresses with logical names. This makes it possible to reach a website and furthermore e-mails reach your recipient. IP addresses can change or be permanently assigned. If you disguise or anonymize your IP address, you have the possibility to decouple your usage behavior from your person, so to speak.
Cookies and your data
Your surfing behavior and settings on your computer are stored on your device via cookies. In addition, cookies enable the linking, transmission and processing of user data and thus allow your recognition or recognition by the website. On the one hand, these can be temporary cookies or permanently stored cookies. For many reasons, web applications try to distinguish between different users by means of cookies – for example, different sessions are required for online banking, social media providers or web mail access for security reasons.
For this reason, cookies store your login data, for example. In addition, with e-commerce providers, the web store is linked to cookies. This allows you the convenience of temporarily suspending your planned purchases and continuing them at a later time. These short pieces of text information are therefore used to identify users, transactions that have been made, or to obtain information about software and hardware equipment. Each time the page that set the cookies is called up, the information is transferred to the web server and user profiles are created or supplemented. Unlike malware, cookies are visible and you have the option to remove them from your browser via the settings.
To prevent your computer from storing cookies, you can manage them in the settings (often privacy settings) of your browser. The management menu includes, for example, blocking, deleting individual or all cookies, or removing cookies after the end of a browser session, but also enabling them.
When you visit websites, they often leave traces in the browser history and furthermore also in the browser cache on your device. Many internet browsers store pages visited, form data or even times of last access as well as much more. The history is essentially responsible for storing the most recently used pages and facilitates the reuse of web pages or search terms. Due to the extensive storage, however, it is also possible to derive statements about your usage behavior from the history. Abuse is possible, for example, via history sniffing. This makes it possible to gain insights into a user’s surfing history.
Therefore, avoid storing historical data or remove it regularly from your device. In addition, private browsing modes or incognito modes are available with most browsers. These private sessions minimize the data permanently stored on a computer.
Tracking users by means of fingerprinting is a young and advanced tracking method compared to cookies, for example. Canvas fingerprinting combines the collection and linking of different attributes and parameters in order to draw conclusions about the identity of a user. In this process, websites analyze the results of interpretations of hidden elements (canvas elements), which are either visible or invisible to the human eye on the web pages.
The interpretation is done through the browser by the computer, smartphone or tablet. The result of this interpretation depends on many factors, e.g. browser extensions, browser settings (e.g. preferred language, date, set time zone, etc.), browser product and version, operating system and applications, but also on the hardware used or conventional configurations (e.g.: screen resolution, installed fonts, etc.). The combination of such information enables the unique identification of individuals.