Retrospective Study of Third-party Web Tracking

Abstract

Web tracking has seen a remarkable usage increase during the last years. Unfortunately, an overview of how web tracking evolved within the last˜15 years is missing. In this paper we present a retrospective analysis using archived data to quantify the usage and distribution of web tracking and how it changed throughout the last decade. We identify a more than five fold increase in external requests between 2005 and 2014. About half of the analyzed websites have a web tracking based inclusion today (2015). As web tracking is often associated with a risk of privacy loss, we also outline the security implications of monopolized ubiquitous tracking.

Tracking on the Web, Mobile and the Internet-of-Things

“…While apps are 'sandboxed' from each other to prevent apps from reading / writing between each other without permission, within their own sandbox apps can generally run whatever code and allow whatever network connections the app developer builds into their app, given the permissions the developer has requested. 28 At the same time, users themselves have very little ability to modify their own device, including in ways which might limit tracking by apps. User access to lower-level operating system functions generally requires an additional, non-standard layer of permission.…”

“…By 2016, 300 out of the 500 top websites were making calls to at least four different APIs which could be used for tracking without cookies, up from less than 50 in 2005 [26]. Another study of the development of third-party web tracking from 2005-2014 found a five fold increase in the number of external requests [28]. There are some silver linings for the privacy-concerned, however, as some early forms of third-party tracking had already diminished or died out by 2016.…”

“…See https://perma.cc/Z6Q8-KYMT28 Although, developers can and frequently do circumvent the permission model, through side-channels (where one app obtains data that it does not have permission for) and covert channels (where an app obtains data via another app which does have permission for such data); see[196] 29 https://perma.cc/73TX-SKCW…”

Good News for People Who Love Bad News

“…Web measurement literature has been documenting the spread of tracking mechanisms at large scale since at least 2006 [17]. Recent studies have expanded the scale and scope of such investigations to document tracking across millions, or even billions, of sites [7,19,35] and examined how practices have changed over time [18,41].…”