The guidelines, available at www.iab.net/standards/ measurement.asp, establish global measurement standards for measuring ad impressions. They call for ad impressions to be counted from the client side, ensuring that viewers actually receive the ad in their browser. The guidelines also define steps to ensure ads are viewed by people rather than robots or spiders and that publishers use consistent cache-busting techniques to ensure proper ad serving.
Greg Stuart, president-CEO of the Interactive Advertising Bureau, which helped create the guidelines, said they are designed to maintain online advertising's commitment to "being the most accountable ad medium."
Online advertising faces unique challenges-and opportunities. While TV, radio and print numbers are audited, they are also based on extrapolated samplings of just a small portion of their audiences. Online publishers, on the other hand, have the ability to report actual use, based on server logs and other technology. However, without global reporting guidelines, advertisers up to now have had no way to be certain that the numbers that publishers report are accurate or counted the same way from site to site or country to country.