As cable internet speeds increase to a gigabit and beyond, you will need a DOCSIS 3.1 modem to be compatible or approved for the gigabyte cable packages that ISPs continue to roll out nationwide. So, what is the best DOCSIS 3.1 cable modem for Comcast and COX? There are only three major contenders, Motorola, ARRIS, and Netgear. The market size is based on the fact that this is a brand-new cable technology, but we have been in the trenches, and we have the best of the best for you, depending on who your cable internet provider is. We have found that most people with Gigabit speed have Comcast Xfinity or COX Cable. Spectrum has yet to approve any modems for 1Gbps.
Best DOCSIS 3.1 Modems – Gigabit Approved
| DOCSIS 3.1 Modem | ARRIS SBG8300 | Motorola MB8600 | ARRIS SB8200 | Netgear CM1000 |
|---|---|---|---|---|
| ISP Compatibility | Comcast Xfinity / COX | Comcast Xfinity / COX / Mediacom | Comcast Xfinity / COX / WOW | Comcast Xfinity / COX / Mediacom / WOW |
| Combo Router | WiFi | No | No | No |
| Download Speeds | 1 Gbps | 3.8 Gbps | 2 Gbps | 1 Gbps |
| Ethernet Ports | 4 | 4 | 2 | 1 |
| Design Style | Black | Sleek Grey | Block White | Slim Black |
| Hardware | Broadcom | Broadcom | Broadcom | Broadcom |
| Dimensions | 2.9 x 8 x 9.3 in | 7.25 x 2.25 x 7.9 in | 5.25 x 5.25 x 1.65 in | 8.8 x 5.4 x 5.9 in |
| Weight | 3.25 lbs | 1.1 lbs | 2.1 lbs | 0.84 lb |
| Status LED’s | 2 | 5 | 4 | 5 |
| User Manual | Link | Link | Link | Link |
| Rating | 9/10 | 10/10 | 9/10 | 6/10 |
| Price | Amazon | Amazon | Amazon | Amazon |
The MB8600 is our top pick, but it is not supported by all ISPs. In that case, the SB8200 is a great runner-up. View our full comparison if you want a detailed breakdown of the differences. Motorola MB8600 vs ARRIS SB8200.
Best DOCSIS 3.1 Modem Router Combo?
When it comes to an approved DOCSIS 3.1 combo modem router capable of 1 Gigabit speed, you can compare your choices. You can choose between the ARRIS SBG8300 and the Netgear C7800. The ARRIS has been much better in this field, and we would recommend it if you must get a combo modem. However, the stand-alone modem with your own router would be a better option.
Gigabit Modem for Comcast / COX / Mediacom / WOW
When it comes to buying your own Gigabit modem to replace the equipment that your ISP rents to you, the choices may vary based on what modem each ISP approves as a compatible and recommended device. DOCSIS 3.1 is currently limited to a few choice modems, as it is a new technology with fewer cable subscribers. However, we do have some heavyweight contenders in the arena, and all of the dominant cable providers continue to deploy new markets nationwide. In the next few years, you can expect to have Gigabit Internet in all major cities.
Note: These modems do not have phone jacks. There are no voice modems for Gigabit available on the retail market.
Best Gigabit Modem For Xfinity Comcast DOCSIS 3.1
With Comcast Xfinity currently the biggest ISP in the United States offering Gigabit speeds, you are likely here for a Comcast Gigabit modem. Not only are they the nation’s largest ISP to offer such speeds, but they are also expanding many new DOCSIS 3.1 networks as they roll out new infrastructure containing the groundwork for Gigabit to many new cities. You can check future Gigabit expansion plans here. As recommended above, the MB8600 is your Comcast-approved and fully compatible DOCSIS 3.1 modem for Xfinity Gigabit.
Best DOCSIS 3.1 Modem For Cox Gigablast
COX offers its own 1Gbps internet package by the name of COX GigaBlast, and it may very well already be available in your market. Check here. They also allow you to replace their panoramic modems with your own fully approved modem. COX recommends that you get one of their approved cable modems for GigaBlast such as the Motorola MB6800 cable modem. It is approved for COX and ready to go with its fastest tier speeds. Source.
But again, there is not a DOCSIS 3.1 modem router combo we can recommend. You will need your own WiFi router.
Spectrum Gigabit Modem
Spectrum also offers a wide array of DOCSIS 3.1 networks for its users to access Gigabit speeds. They have a list of Gigabit cities here.
Spectrum claims it will offer 1Gbps speeds to all of their customers nationwide by the end of 2018. They also say the minimum speed they will offer for any customer is 200Mbpps, but at the same price as their current 60Mbps prices. This means many users will have no choice but to upgrade their existing legacy equipment to higher-end, fully compatible Spectrum modems.
Now here’s the kicker. Spectrum has zero approved modems on the retail list for DOCSIS 3.1. Some customers have said the MB8600 has worked for them, while others stated it has not. So at this time, you have no option but to rent a modem from Spectrum if you plan on using their Gigabit speeds. I assume this is a strategic money grab on their end because the MB8600 works fine with Comcast Gigabit and COX Gigablast.
I will call Spectrum and ask them, but if you have, please let us know in the comments below.
Mediacom Gigabit Modem
Mediacom is coming fast with the Gigabit internet and lets you buy your own replacement modem as well. They even give you multiple options, such as the SB8200 or the CM1000. Source.
RCN Gigabit in Boston
While RCN is only serving the Boston area with its Gigabit plan, it will soon expand to the rest of the East Coast. But they are struggling to certify any DOCSIS 3.1 modems for their Gigabyte network. As it stands, you are unable to buy your own replacement modem. Source.
Wide Open West Gigtopia Modem
Wide Open West, also known as WOW offers Gigabit internet with the following modems. The SB8200 or the CM1000. Source.
What is a DOCSIS 3.1 Modem?
DOCSIS or Data Over Cable Service Interface Specification is a standard set for international telecommunications companies. Created by CableLabs, it is designed to allow cable TV providers to send high-speed data transmissions over the currently existing CATV network(Cable Access Television). DOCSIS 3.1 is the newest standard and has been around since the year 2013. However, not until recently have cable internet providers started offering high-speed packages such as Gigabit Internet. To utilize these higher-tier Gigabyte packages, you must use a compliant DOCSIS 3.1 Modem.
The current generation of cable modems is DOCSIS 3.0, but the future is arriving, and it is DOCSIS 3.1. The past standard, which has come and gone, was DOCSIS 2.0.
History of DOCSIS release dates:
DOCSIS 1.0 – March 1997
DOCSIS 1.1 – April 1999
DOCSIS 2.0 – December 2001
DOCSIS 3.0 – August 2006
DOCSIS 3.1 – October 2013
As you can see, the DOCSIS 3.1 standard has a long life ahead of it, and it’s barely even just getting started. Gigabit internet speeds will last a long, long time and won’t get replaced anytime soon. As it stands, there is no need for higher-speed modems. Maybe if we start streaming holodeck simulations or something fantastic. One can wish. They are toying with DOCSIS 3.1 Full Duplex, which could host speeds up to 10Gbps, but there is no network or equipment in place for this. They will do as much milking of Gigabit speeds as they can before spending on such an upgrade.
DOCSIS 3.1 Modem Options
Now you have the best options for major cable providers such as Comcast Xfinity Gigabit internet. You are well on your way to the fastest internet you ever even began to imagine. The truth is you probably won’t even know what to do with all of that bandwidth. It is quite excessive.
DOCSIS 3.1 Approved Compatibility Chart
| MODEM / ISP | ARRIS SBG8300 | Motorola MB8600 | ARRIS SB8200 | Netgear CM1000 |
|---|---|---|---|---|
| Comcast Gigabit | Yes | Yes | Yes | Yes |
| COX Gigablast | Yes | Yes | Yes | Yes |
| Mediacom Gigabit | No | Yes | No | Yes |
| WOW Gigtopia | No | No | Yes | Yes |
| Spectrum Gigabit | No | No | No | No |
| RCN Gigabit | No | No | No | No |
Again, we recommend the MB8600 unless it is not yet approved. In that case, the SB8200 is a mighty fine DOCSIS 3.1 modem for Gig speeds. You can see what modem is approved for what ISP. The MB8600 is approved for Comcast, COX, and Mediacom. Unfortunately, it is not yet compatible with Spectrum and WOW. Spectrum and RCN has yet to approve any 3.1 modems.
Nice summary. Thanks. I was just in shopping mode for Docsis 3.1 modem with voice. Xfinity actually had two options, Arris T25 and Netgear CM1150V. I ordered the Netgrear product and was impressed by the ease of installation and the number of Gb ports. However, neither product has a battery backup option for the voice, which I thought was an FCC requirement for reaching 911 during a power outage.
So, working with Xfinity, I actually kept my old Arris TM822G and had it configured as an MTA (only). I ordered the Arris SB8200 which has not been easy to install. After finally getting it installed my performance direct connect through a Gbps Ethernet port rarely exceeds 100Mbps down and 5Mbps up. Any ideas what the problem might be? Xfinity suggests that I contact Arris, but I am suspicious it is an issue with their infrastructure I hate getting caught in the middle of a finger-pointing exercise.
If both modems are connected, I could see that as being the issue but do not understand the setup between the TM822G and the SB8200.
I’m looking for a spectrum approved docs 3.1 voice/internet/wifi combo gateway to replace the one I’m currently renting from spectrum. Any suggestion?
Spectrum has not approved any such devices yet.
The MB8600 being faster is based upon the number of ethernet ports. If you check, you will see that the MB8600 has deleted the extra ports now, and only offers this unit with 1 ethernet port.
Is the Arris as a better choice with 2 ports?
Can you confirm my assessment?
Please reply, as I am stuck between the 2.
While they have used a yellow sticker to cover the extra ports, they are indeed still there.
As mentioned, they just are not used or supported by anyone yet.
This port bonding feature is still just a possible future enhancement but currently disabled and as you know, now covered.
They covered the extra ports because people thought they were for routing and when it did not act as a router they thought the device was not functioning properly.
I am getting Xfinity triple play with speeds up to 1GB. This means I need the Netgear CM1150V because it has GB speed and Voice. Which router go you recommend?
It’s going to come down to a few things.
The size of your house, the router placement, and of course the router top speeds.
When you have 1GB, you don’t actually maintain that speeds over wireless but hardwired it is possible.
With the right router you can have multiple wireless connections at high speeds but none will pull a full Gigabit.
Here’s a guide to buying a router.
For someone who knows almost nothing about how the internet works my dilemma is we recently moved to Florida and have Spectrum internet. We had a brand new router-modem combo but the device had to go in one bedroom and on the other end of the house our connection will not stay. We only have 30mbps. My question is if i go with spectrums modem and router will we have better range? We were told it is probably because of concrete and steel walls that we can’t get the distance we want. Also bought a Linksys range extender and can’t even get it to connect in the same room as modem/router
The problem is that if you have concrete and steel walls, you’re not going to be able to penetrate them with a stronger router. These obstacles still impede your wireless network range.
The only real option is to run a long cat5 cable from the modem to a router on the other side of the barrier and cast the signal from there. If you were to accomplish this method, any router we recommend above shall do once you reach around the concrete and steel walls.
I’m buying a Motorola MB8600 modem to use with Mediacom cable internet, do I have to buy a router?
Installers of Mediacom told me their modem has a router inside of the modem. Is this TRUE?
Yes, you will still need a router because the MB8600 is a cable modem only.
If the Mediacom cable installer technician told you they issue a combo modem router, then it is true.
But you would still benefit from buying your own modem and router.
How do I get phone service thru Cox if the newest Docsis3.1 doesn’t have a phone jack?
You are stuck with their equipment.
Where does Cablevision fit in the equation? I have Optimum 300 and considering 400 but it is packaged with VoIP. Can’t seem to find a DOCIS 3.1 modem with Telephone. Does VOIP interfere with higher speeds.
I have VoIP because of Optimum bundles but we never answer that line. So can you direct me to the best of the new routers, compatible with Optimum 300 and 400 speeds with or without VoIP?
Cablevision, aka Optimum, has terrible support and no answer to this question. They will continuously loop and refer you to a dead webpage or to their store which does not give you any options for DOCSIS 3.1.
The best thing you can do is call and debundle the voice so you may use a good DOCSIS 3.1 modem with your own router. If you really need the savings bundle, maybe they have another option to throw in there.