I've always been told that once you have AdSense on your webpage or blog, you are not allowed to try and get artificial traffic from traffic exchanges and autosurfs. But how would you control something like that? Anybody in the world could take one of your blog posts and put it on an autosurf and you would have no way of knowing who did it, and you couldn't make them stop even if you did know who it was. So how could Google ban you for something that you have no control over?
Well, you should an email to Adsense support if you're concered about this and I'm sure they'll block it for you.
By watching your logs, impressions, frequentIP's, etc you can catch something like this.. then if you see something suspicious you could remove your ads and report it to google. There are also tools you can use that will stop/block many/most fully-automated systems like this. One good one is Bad-Behavior..