Over the past week, a number of the Internet’s largest data carriers have ceased providing online connectivity to Atrivo (a.k.a. “Intercage”), an ISP that security experts say is home to a huge number of scammers and spammers. This week, I’m turning the spotlight on EstDomains Inc., Atrivo’s most important customer and the single biggest reason so many experts have condemned Atrivo. According to RegistrarStats.com, EstDomains is the 49th largest domain name registrar, with more than 270,000 domains. Security Fix is still working on cataloging all of those domains, but for the purposes of this analysis we’ll examine some 10,000 Web site names that are both registered through EstDomains and using the company’s various domain name servers to route traffic to them. I chose to focus on that particular subset of 10,000 domains mainly so that EstDomains could not simply disavow knowledge of the sites’ activities by claiming it serves as