OK I got my new SB6141 modem today and plugged it into my router in place of the old SB5101.Very easy to authorize a new modem through TWC. When I activated my SB6183, all I had to do is go online and use their website. I did need a Cable bill for the account number, but TWC makes it as easy as possible. Does not matter if you have a wireless router as all modems will be locked into a walled garden, until it is activated as a Comsonics modem as the billing system can only identify customer owned modems as comsonics. If you have a TWC login, you can activate your modem using that, but it was tempermental and I had to use billing information such as my account info through a cable bill.
Also, if it does not redirect you just type in www.activatemymodem.com as that will give you the instructions to do so.
After the power up sequence, I can get to the cable modem status page at http://192.168.100.1 but I can't get to any online activation page.
Even trying the direct URL www.activatemymodem.com in my browser doesn't do anything.
Of course I can't get to the TWC website with the new modem since its not authorized yet.
Isn't it supposed to be able to access some webpage for authorization even when not authorized?
I also tried plugging the modem directly to my computer via ethernet bypassing the router, same result.
I had to switch back to the old cable modem to get online again for now.
Seems like you still have to call TWC by phone and give them the new MAC address like I did years ago for the older modem?