Originally posted by: ImDonly1
DOCSIS 3 is the new tech Comcast is rolling out it delivers speeds up to 50 Mbps right now. Docsis 2 I think stops at 20 Mbps for Comcast for now? The Docsis 2.0 modems support up to like 30 something Mbps. So in the future when Comcast upgrades speeds for free as they have done in the past you will already have a Docsis 3.0 modem. If you want to still buy a Docsis 2.0 modem then you can still do that, but I think people are recommending Docsis 3.0 ones for future proofing. There are not that many docsis 3 modems out as it is a new tech and most people just rent them I think. One of the ones that Comcast uses is the Motorola SB6120 it costs about $95 at Frys.com or Amazon.com search around. They also rent out the Cisco DPC3000 but I am not sure how easy it is to find those to buy. I know the Motorola SB6120 can be bought. Not sure about other docsis 3 modems. Here's the cheapest SB6120 I could find from JR.com
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For docsis 2.0 modems the most popular ones are the Motorula Surfboard SB5101 and SB5120. They can be had for like $40 from Newegg, Amazon, etc. eBay has cheap ones and that is where I would probably buy one from.
Not sure about wireless N routers. Checkout broadbandreports.com the Forums for more info.
This thread about docsis 3 has most of the FAQs
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Note, that your area might not have docsis 3 yet, but will sooner or later.