In a chapter focusing on how Fox utilized its notoriously ruthless public relations department in the mid-to-late 00's, Folkenflik reports that Fox's PR staffers would "post pro-Fox rants" in the comments sections of "negative and even neutral" blog posts written about the network. According to Folkenflik, the staffers used various tactics to cover their tracks, including setting up wireless broadband connections that "could not be traced back" to the network.
From the book itself:
Fox PR staffers were expected to counter not just negative and even neutral blog postings but the anti-Fox comments beneath them. One former staffer recalled using twenty different aliases to post pro-Fox rants. Another had one hundred. Several employees had to acquire a cell phone thumb drive to provide a wireless broadband connection that could not be traced back to a Fox News or News Corp account.
Folkenflik's book has already roiled News Corp with its account of Wall Street Journal staffers who found their attempts to report on the company's phone hacking scandal met with roadblock after roadblock. (The company denied the account.)