Some internet service providers (ISPs) are serving their own ads into clients webpages without their knowledge or permission, according to new US research reported by ClickZ.
Researchers from the University of Washington developed a computer program to find if HTML (the programming language from which most websites are built) is being changed between leaving its publisher’s server and being viewed by the user.
Applied to more than 50,000 IP addresses supplied by volunteers, the program uncovered more than 700 instances of websites being altered between publication and viewing.
While the majority of these changes were attributable to pop-up blockers operating on the end-user’s computer, 16 of the 700 changes were found to originate from the ISP serving the website.
The researchers found that in those 16 cases the ISPs had served their own advertisements into the websites in place of the ads the website owners had arranged. The result? A little extra revenue for the ISP, and a little less for the website owner.