PRINCETON, N.J., Feb. 28 -- RCN Corp. and Starpower Communications, its joint venture with Pepco Communications, have signed a five-year, multimillion dollar agreement with Qmedia Inc. to provide fiber rings in New York City and Washington. Terms were not disclosed. RCN said each ring will connect six locations to Qmedia's hub site in each city and provide connectivity to Qmedia's national fiber optic network, which is being built for broadcasters, producers, media distributors and other media-centric companies. Installation is expected to be complete by June 2002.