AT&T and MetroFi submitted a joint proposal to operate a municipal Wi-Fi network in Riverside, California, that covers 65 square miles. The proposed project has similarities to the Google-Earthlink partnership for San Francisco. The AT&T MetroFi network will be supported in one of two ways. First, advertising will be inserted into Web pages that users visit. This naturally suggests there will be some friction with Web site operators, which will not want ads run on their content. For example, imagine ticket broker advertisements placed on top of TicketMaster.com content pages — not likely. The second option will offer an ad-free service billed through AT&T for $19.95 a month. It will be interesting to watch what transpires overall in the ad-supported model.