according to foreign media reports, the researchers found that there is a very difficult to get rid of the new online tracking tool is used to follow up from the White House official website to porn site YouPorn.com popular site visitors.

, according to researchers at the Princeton University and Leuven University of Belgium’s disclosure, operation principle of the name "canvas fingerprint identification" tracking technology is drawn: Web browser guide visitors to the hidden image. Because of the different images of different computers (such as different fonts, different software, different clock settings), the images can be used to assign a unique identifier to each user.

, like other tracking tools, is used to create a profile for people visiting a web site. Those files help push them to the relevant ads, articles and other types of content.

but this technology is very difficult to shield, standard web browser privacy settings or AdBlock Plus and other anti tracking tools can not stop it.

researchers found that in 5% of the top 100 thousand sites, there are computer code for the identification of canvas fingerprints, mainly from a company called AddThis. The site uses AddThis’s social media sharing tool. Fingerprint identification code canvas other manufacturers including Germany digital marketers and Canada Ligatus dating website Plentyoffish.

AddThis CEO Ricci · Harris (Rich Harris) said the company began testing canvas fingerprint identification technology in earlier this year, making its potential as an alternative to traditional user tracking way of "cookie".

"we want to find a replacement for cookie." Harris said in an interview.

said the company had considered the privacy implications of canvas fingerprinting before starting the test, but ultimately concluded that it was in line with current regulatory policies".

he added that the company only through the use of canvas fingerprint data collected by the internal development, if the user in the computer installed AddThis selected cookie, the company is not using the data collected by the directional advertising or provide personalized service.

led the research team of Princeton University computer science professor Elvind Narayanan (Arvind Narayanan) retorted, forcing the user to believe that the best way of privacy protection in their own words is not AddThis.

AddThis did not notify the relevant sites they are placed in the code. According to their spokesman, this is because they need to carry out R & D projects in an active environment, in order to obtain the best test results.

added that the company did not collect any data used for targeted advertising