Comcast in the San Francisco area be my cable and internet provider . I have rent they modem at $ 3 a month for many year . they do I a favor when it be announce that they would be increase they modem rental to $ 5 a month ! I buy the Linksys cm 100 Cable Modem , make by Cisco , after read a review of how good it work with Comcast , with faster speed than when use the Comcast modem . installation be easy , BUT , remember to unplug you router if you have one , and plug the modem directly into you computer for installation . it would have be nice if the installation direction and cd which come with the modem make that very clear , because , even though I show connectivity , when I call Comcast to give they the MAC number and get my new modem register with they , I could not get a browser to open up . Comcast have always be very helpful if I have ever have a connectivity problem , and that be the first question they ask : do I have a router ? once I disconnect the router and reinstall the modem with the CD , which take 2 minute , Comcast get I online and my browser come up right away , and I reconnect my router with no problem since . in less than a year at $ 5 a month my modem will have pay for itself with the one time cost . I be very happy with it , and thank Comcast for save I money in this regard !