well my old DOCSIS 2 modem begin to loose speed and would disconnect frequently . it be a good 5 or more year old . so buy this and set it up with comcast real easy , call the service number say I want to give the mac address of my new modem and service be back up and run in a few min . now I be get increase speed , and no more trouble with comcast . unfortunaly the router will be the next thing to be replace as the router be limit my speed now . but this product do it be job and do it well with my comcast internet .