I have 2 house set up with 2 different cable company , both of which use the Motorola SB6121 Modem . initially , I use a Motorola Modem with a 1.0 docsis at my Florida home but internet service be intermittent . I replace the modem with the sb6121 and the problem be cure . when Mediacom start charge a monthly fee at my Iowa home , I immediately purchase another sb6121 and return the Mediacom Modem . the Motorola sb6121 perform flawlessly in both Florida and Iowa home and that be the name of the game : reliability .