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DOCSIS 3.0 vs. 3.1 vs. 4.0: Comparing the Differences
Seven years separate the two technologies, but both are relatively old by today's standards. That said, 3.1 may still be more advanced than you need.
If you choose speeds above 1 gig and rent your equipment, you'll receive a modem-router combo that comes with DOCSIS 3.1 built-in, so you don't have to worry about your modem's specifications. Otherwise, if you choose to use your own equipment, you'll want to spend a little extra for a DOCSIS 3.1 modem to take full advantage of the plan's speed potential. At present, Comcast's Xfinity is the only major cable internet provider that has started rolling out DOCSIS 4.0 in the country.
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