DOCSIS is the international standard that dictates how cable modems work. It stands for “Data Over Cable Service Interface Specification” and while that sounds complicated, it’s just the set of standards that ensures that all internet access over cable is regulated the same way and works with the same devices. Like most protocols for electronic devices, it evolves over time to increase performance, reliability and security. The last several years have seen an increase in consumer broadband speeds, so the DOCSIS 3.0 standard has begun to phase out gradually in favor of version 3.1. While newer is generally better, there are various reasons why you might not need a high-tech DOCSIS 3.1 cable modem.
Today’s consumer technology is highly streamlined compared to decades ago — in fact, the term “Wi-Fi” is practically synonymous with “internet connection” for many people. To understand the job of the cable modem itself, first keep in mind that your Wi-Fi connection is simply the wireless network that your router creates and your computer, TV and smartphone all connect to. It’s entirely possible to have a Wi-Fi connection with no internet access and a decent number of users take advantage of their Wi-Fi network to communicate with home servers where they store collections of movies, music and other data.
The modem, specifically, is the device located between your wireless router and the physical connection entering your home. Be aware that if you’re lucky enough to have access to a fiber internet connection, you won’t actually need a modem, but instead an optical network terminal. Functionally, an ONT is similar to a modem, but there are different types for different connections and users of fiber connections should consult directly with their internet provider to determine which is right for them.
If you’re among the millions of Americans with access to cable internet, you will need a cable modem. There are devices that include both a modem and router built in, but those aren’t recommended for most users because they can be unreliable and often don’t receive security or performance updates as regularly as standalone modems and wireless routers.
It’s likely that your internet service provider offers a rental modem that should work reasonably well. However, ISP-provided modems are notorious for being somewhat old and not quite up to par, especially if you’re paying for a very high-speed cable connection. In those cases, buying your own modem is a great investment that can pay off by lowering your internet plan costs and increasing performance, stability and security in the long term.
Version 3.0 was released in 2006 and gained ground over the next few years as high-speed cable internet access became ever more popular. At a basic level, it supports maximum download speeds of up to one gigabit per second (or Gbps) and uploads of up to 100 megabits per second (or Mbps). Since it’s been around for roughly 15 years, you might think at first that it’s an obsolete technology and you should avoid a DOCSIS 3.0 cable modem, but it’s a little more nuanced than that.
The 1Gbps peak throughput of a DOCSIS 3.0 modem is higher than you’ll need for any kind of everyday browsing. For example, even streamed 4K video only eats up a couple dozen Mbps (via Netflix, at least). While more and more consumers have access to 1Gbps cable internet plans, only a small percentage of users actually need or subscribe to those gigabit-class plans.
A much more reasonable and common speed for most consumer internet services is in the 100 to 200Mbps range. A DOCSIS 3.0 modem can easily accommodate that, as well as a decent number of simultaneously connected devices, without seeing a noticeable drop in performance.
Keeping in mind the fact that many users simply don’t need anything faster than DOCSIS 3.0 (and likely won’t for quite some time), the big pros of using the older protocol are that the modems are significantly less expensive and there are a lot of great options to choose from.
Like any old technology, DOCSIS 3.0 does have some drawbacks. While its theoretical peak throughput is 1Gbps, it might not actually get the absolute best performance out of a cable internet connection in the 400Mbps range or higher. This is just because peak performance numbers almost always refer to the best possible scenario, while in real-world usage, things never work out quite so cleanly. If you work professionally with large amounts of data and you often find yourself making large uploads, DOCSIS 3.0 can end up in a bottleneck. You’ll experience a greater bottleneck if you have many devices connected to your network and are actively using your internet connection at the same time.
Another downside worth mentioning is that DOCSIS 3.0 doesn’t quite have the same security features as its newer relative. A lot of these — WPA3, for example — aren’t required for most common use cases and can actually be a few years off in terms of full implementation across the worldwide web. But it’s worth noting that DOCSIS 3.0 is somewhat on the downturn, even if it’s happening very slowly.
This is just about the highest-performing DOCSIS 3.0 modem on the market and it can easily accommodate the majority of home internet connections.
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The Motorola is notable not only because it essentially maxes out the DOCSIS 3.0 protocol, but also because it’s explicitly approved for nearly every cable internet provider in the country.
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The specifications for the latest cable modem protocol were introduced in 2013, but we’ve only recently seen significant lineups of DOCSIS 3.1 modems hit the market. With 10Gbps download and 1Gbps upload speeds, DOCSIS 3.1 can accommodate the fastest consumer internet plans on the market.
Clearly the most noticeable upside is that DOCSIS 3.1 is 10 times faster than version 3.0. If incredible upload and download speeds are crucial to your workload, then DOCSIS 3.1 is the way to go. There are also several security enhancements baked into DOCSIS 3.1 that ensure your device and network will be protected years down the line.
Another reason to consider a DOCSIS 3.1 modem is online gaming. Especially if there are multiple competitive gamers in your household, the latest cable modem standard can help better manage packets (the actual groups of data that are transported across the connection) and make for high-efficiency, low-latency networking. This is due partly to the fact that DOCSIS 3.1 supports more simultaneous data streams at a single time, with the top-level specification known as 32x8 bonded channels, which refers to 32 downstream (download) channels and 8 upstream (upload) channels.
Also, just to be clear, DOCSIS 3.1 modems are designed to be 100% backward compatible with DOCSIS 3.0 connections. While you shouldn’t run into any problems there, it’s always wise to check with your ISP to make sure that your prospective new DOCSIS 3.1 modem will work perfectly with their service.
The simplest and most notable drawback to DOCSIS 3.1 modems is that they tend to be pretty expensive, often running twice the cost of DOCSIS 3.0 modems or more. There’s one more major thing to be aware of, and it has to do with product availability and a major flaw in certain DOCSIS 3.1 modems.
Without writing a book on how modems and their respective chipsets are manufactured and configured, one of the first major DOCSIS 3.1 chipsets — called the Puma 6 and manufactured by Intel — shipped with glaring hardware errors that apparently can’t be fixed with a firmware or software update. These chipsets are highly prone to a phenomenon known as “jitter” in addition to general, unpredictable latency spikes. In some cases, the jitter and latency render the modem (and therefore the internet connection) unusable at times. Avoid any DOCSIS 3.1 modems built around the Puma 6 chipset and many that use the Puma 7 chipset. While it’s not a guarantee that every one of these modems will fail, there’s a decent chance that they will and you should, therefore, avoid them.
With 32x8 bonded channel performance and the latency-reducing and security-enhancing DOCSIS 3.1 is lauded for, it’s hard to go wrong with this one. It’s compact, performs great, and isn’t terribly expensive.
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If you’re dead set on peak performance, consider this 2Gbps-ready modem that offers extensive compatibility with most ISPs around the country. It’s not exactly cheap, but it’s an investment that should last a long time.
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This one’s not for everyone. It’s actually specifically for subscribers to Xfinity’s voice-enabled internet plan, which combines gigabit-class internet speeds with high-definition voice calling. If you want to get the most out of your Xfinity account, get this one. If you don’t have Xfinity by Comcast, count this one out.
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If your household doesn’t require huge amounts of bandwidth and you don’t want to shell out a fortune, a new DOCSIS 3.0 modem should serve you well for a few years.
On the other hand, if you want to get ahead of the pack and ensure that you’re getting the most out of a gigabit-class internet connection for the foreseeable future, there’s nothing wrong with investing in a modern DOCSIS 3.1 modem — as long as you avoid models built around the Intel Puma 6 or 7 chipsets. In fact, now that there are finally some great DOCSIS 3.1 modems available at decent prices, now is a great time to buy.
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Chris Thomas writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
