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It seems that most cable modems on the market today are DOCSIS 3.0 (ex).

However, "recently" (2013), DOCSIS 3.1 was announced.

I'm assuming (perhaps incorrectly) that as of now, finding DOCSIS 3.1 cable modem is either hard, or more expensive, given most of the popular ones seem to be 3.0. As such, the question arises as to whether 3.0 is "good enough" or should I bother with wanting 3.1.

What are the tangible benefits from having DOCSIS 3.1 cable modem vs. 3.0 for an average Internet user?

Clarifications to help narrow the question down:

  1. Assume that cable service provider does, or shortly will, support 3.1
  2. Assume that the modems are otherwise identical (e.g., yes, 3.1 will be a newer modem with hopefully newer and more powerful hardware, but that's not due to 3.1 specifically).
  3. Assume average Internet use. Several PCs and cell phones behind a router. Web browsing, some gaming, some youtube, light video streaming (e.g. Amazon Prime). Occasional heavy downloads (e.g. Linux distros, or buying software online). Occasional video conferencing.
  4. Internet connection speed does not exceed 50Mbps upstream or 100Mbps downstream (as in, I'm not buying service that's faster than that in the foreseeable future)
DavidPostill
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DVK
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3 Answers3

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High bandwidth plans entirely miss the other major benefit of DOCSIS 3.1: active queue management.

If - and this is a big if - your provider also supports DOCSIS 3.1, you will benefit from Active Queue Management. AQM is intended to solve bufferbloat, where network devices such as cable modems buffer data in an attempt to increase link utilization at the expense of variable latency. Bufferbloat wreaks havoc with TCP's congestion control algorithm. Instead of real-time rate adjustment in the face of packet loss - what TCP expects on a saturated link - congestion control kicks in only after the buffer fills. If the buffer is large the user sees a pause and latency increase while the buffer drains at the reduced rate. TCP then slowly increases the rate as the buffer fills back up, and the cycle repeats. This whipsaw effect has a huge impact on perceived performance.

Even in the 10s of Mbps you may see vastly better day-to-day web, streaming, and gaming performance with DOCSIS 3.1 hardware - again, assuming your provider also supports the standard.

jbyers
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No there will be no benefit for you to buy a DOCSIS 3.1 modem vs a DOCSIS 3.0 modem, especially based on criteria #4, does not exceed 50Mbps upstream or 100Mbps downstream (as in, I'm not buying service that's faster than that in the foreseeable future)

Taken from here DOCSIS 3.0 supports the following: 152Mbps Download, 108Mbps Upload.

DOCSIS 3.1 was made for gigabit speed internet. It supports the following, a whopping: 10,000 Mbps download, 1,000 Mbps upload.

Unless you plan on having multi-gigabit connections very soon, you don't have any reason to buy a DOCSIS 3.1 modem.

DrZoo
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Comcast, for business accounts, appears to limit DOCSIS 3.1 to tiers of 500mb/s or higher: http://forums.businesshelp.comcast.com/t5/Equipment-Modems-Gateways/Arris-SB8200-Has-No-DOCSIS-3-1-Upstream/td-p/34069

At this time DOCSIS 3.1 capabilities are reserved for our 500 Mbps and 1Gbps speed tiers. Additionally, your business location must be in range of a DOCSIS 3.1 enabled headend and have a DOCSIS 3.1 enabled modem (which you do have). If your business does meet all three of these qualifications you will be automatically on our DOCSIS 3.1 network for both upload and download.

user320582
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