The debate raised by revelations of NSA surveillance has drawn our attention to how we are being tracked online. Sebastian Huempfer describes a new tool to show us how those electronic cookies crumble.

At a TED conference in February 2012, Mozilla CEO Gary Kovacs presented Collusion, a new browser add-on that allows internet users to monitor and control who is tracking them online. According to PCWorld, “Collusion was originally developed as an independent project by Mozilla engineer Atul Varma. Mozilla is now developing the add-on with the support of the Ford Foundation.”

Collusion can be downloaded free of charge for different web browsers (Firefox, Safari, Chrome, Explorer) and integrates with the web browser used to navigate the internet. Once activated, it generates a real-time interactive spider-web graph showing which sites the user has visited, and which third-party sites have been informed about each visit.

The visualisations are interactive: if the user clicks on a node, Collusion provides a list of all websites that sent this website information, or all websites that were sent information about the user’s visit to this website. Collusion also tells the user whether the informed website is a “known tracking website” or a normal website, and lets the user block such “known tracking websites”. Many of these sites are used by behavioural trackers, companies which create user profiles based on website visits for commercial purposes including targeted advertising.

Collusion thus makes it easy to spot when several websites relay information to the same tracking website, which could enable that website to build up a profile of the user. According to Mozilla, the information collected by Collusion is only stored locally on the user’s computer and deleted automatically. Mozilla is also planning to offer an opt-in service that allows users to share their Collusion data, thus creating a “global database of web tracker data” for researchers and journalists.

Gary Kovacs argues that Collusion gives consumers the power to prevent harmful tracking and thus protect their privacy by letting them monitor who is tracking what. According to Kovacs, behavioural tracking was a $39bn industry in 2012, and is taking advantage of insufficient consumer protection against hidden online tracking.

Here’s an example of how Collusion works: a visit to Al Jazeera English via Google using Google Chrome (left) and Firefox (right). In each case, a number of websites were informed about the visit to AJE, incl. Facebook and two “known tracking sites” in Google Chrome.

When Mozilla’s CEO introduced Collusion, he said that he was particularly concerned about children being tracked when they use the internet, so here is an example of the visualization after a visit to five children’s websites (selected from ebizMBA’s “Top 15 Most Popular Kids Websites May 2013”). Google Analytics was informed about 4 out of 5 website visits; known tracking websites wunderloop, scorecard and doubleclick (owned by Google) were informed about 2-3 our of five vists.

A day’s worth of using the internet generates much larger networks of information sharing. The visualisation above is of a Google Chrome session that included visits to Google, Gmail, LinkedIn, Twitter, Facebook, BBC News, the Guardian, Spiegel Online, Oxford’s SOLO, WordPress, Reddit, Youtube, Wikipedia and my online banking (while being logged in at all those sites). Only the blue nodes present websites that I visited; the red ones are “known tracking sites” and the grey ones other third parties that were informed about my browsing history. Even doing research and reading the news using Firefox – while never logging into Facebook, Twitter, LinkedIn or any Google service – for a few hours builds up a vast network of information being shared. Knowledge is power, and Collusion at the very least gives internet users the power to know who is keeping tabs on their browsing history – although it can not tell you what the NSA knows about you.

Sebastian Huempfer is associate editor of Free Speech Debate.

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