Russ has posted an entry about Google AdSense, possible fraud and abusive terms&conditions. It's good reading, and since I can't add anything to it I'm going to go off on a tangent from there.
The idea that caught my eye is in the update to the article - the fraud-monitoring software. I'm thinking about how can traffic that isn't fake can seem like bad traffic to a monitoring algorithm?
My first thought is inspired by one of my minor annoyances in recent times - HTTP proxies.
It is conceivable that a certain number of people behind a proxy find an advertisement on a site interesting and click on it, all in a short length of time. If the algorithm isn't proxy-savvy (i.e. knows how to interpret X-Forwarded-For headers) or the proxy isn't compliant (not all of them are), then the monitoring software could be fooled by honest traffic.
This is not a far-fetched idea, most big ISPs use proxies, which they automatically configure from their install CDs. And some, in particular Telefonica here in Spain, give you no choice by installing a transparent proxy, which is the root of all evil. :) If the AdSense monitoring software is not proxy aware, then it would throw out sites like ADSLNet or BandaAncha because anyone in Spain using ADSL will appear to come from the proxy IP (currently 80.58.4.42, if you really want to know), even if the clicks were from many different people.
And of course, this causes other problems for me. I don't know how other people in Spain keep track of how many individual users use their site, but I can't do it since I use shared hosting and can't change the Apache config to log real IPs instead of proxy IPs. I get lots of hits in my logs from the proxy, but I am also behind that proxy and I use my domain for quite a few other things, so most of those hits are probably mine. :) Anyway, if you're in Spain and using ADSL, leave me a comment so I know you're there!
Posted by Dave at October 2, 2003 12:33 PM