I know up-front from other review that get this modem to work as a replacement for my old docsis 1.5 + + surfboard would require talk to the folk at comcast , and restart several computer and a router . the changeover be simple once I get past Comcast 's hell-spawned robot answering system with its vehement attempt to `` help I '' and be able to speak with a person in billing . yes , it be billing which handle the whole `` MAC Address to customer id '' mapping ; they also provide I with the answer the outsourced customer service could not , regard whether and how much I would pay and benefit from a higher price datum plan . it be well worth it . I have to reset the cable modem three time -lrb- one be because my netgear wifus router become confused -rrb- and then , even with two people do fairly high-bandwidth-intensive thing , I have be very happy . my only downside : this unit come with yet another wall wart .