The online advertising industry is marshaling a fresh effort to fight click fraud, which steals money from advertisers and undermines faith in online campaigns.
The latest effort is focused on automated traffic caused by bots from within data centers that is intended to trigger ad impressions, according to the Trustworthy Accountability Group (TAG), an industry body.
TAG is going to initially use a blacklist maintained by Google that lists suspicious IP addresses of computers in data centers that may be trying to replicate human clicks on advertisements. Ad-focused technology companies, including Facebook and Yahoo, will also contribute.
A study from the National Association of Advertisers last December estimated marketers would lose US$6.3 billion this year to click fraud out of a total of $48 billion in spending on video and display ads.
A long running effort has been under way to detect and block fraudulent clicks in order to keep online advertising rates from falling and stem doubts about its effectiveness. But fraudsters continue to innovate new ways to cheat the industry.
Some unscrupulous publishers have been harnessing the power of virtual machines in data centers, wrote Vegard Johnsen, a Google product manager for Ad Traffic Quality, on a company blog post.
Click fraudsters have been using a program called UrlSpirit to generate fake clicks on ads. URLs are submitted to the application, which then uses Internet Explorer to visit the list of websites. Many copies of the program may run in a data center, generating large numbers of fake clicks.
"In aggregate, the data-center installations of UrlSpirit were generating a monthly rate of at least half a billion ad requests -- an average of 2,500 fraudulent ad requests per installation per day," he wrote.
Another fake click program is called HitLeap. Instead of Internet Explorer, it uses the Chromium Embedded Framework to visit Web pages for a certain amount of time specified by a publishers, Johnsen wrote.
HitLeap requires its users to earn "browsing" minutes, which are collected by running the application on their computer. Browsing minutes can also be purchased for $9 for 10,000 minutes.
"For example, 10 browsing minutes will get a publisher five visits if the publisher requests two-minute visit durations," he wrote.
About 16 percent of HitLeap's total network was installed on virtual machines within data centers as of mid-June. Many of the websites visited by HitLeap were entirely constructed in order to carry out click fraud.
"For example, of the top ten webpages visited by HitLeap bots in June, nine of these included hidden ad slots -- meaning that not only was the traffic fake, but the ads couldn't have been seen even if they had been legitimate human visitors," he wrote.
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