As a Network Engineer, I have bought the Motorola MB8600 and tested it for four weeks.
And after these four weeks, I can say that it’s a good and reliable modem that goes for a suitable price.
It will be a great option for many, but unfortunately, not everyone.
Keep reading to learn more about my conclusion in more detail.
Motorola MB8600 Overview
The Motorola MB8600 is a modem made for you that don’t want to rent a modem from your ISP. But instead, buy one of your own.
The device is a DOCSIS 3.1 cable modem capable of supporting internet plans up to 2000 Mbps. It only works for cable internet, do not get it with any other type of internet connection.
I couldn’t confirm that it could reach 2000 Mbps due to not having access to such an internet plan. But I have no reason to believe it wouldn’t be able to.
I recommend the Motorola MB8600 for you looking to get a modem, and then stop thinking about it. Because this modem will be enough for years to come.
That said if you are switching to fiber in the coming future. Then you might not want to get this modem. As it’s excessive for many internet plans today. If that is the case, you can then check out the alternatives at the bottom.
I should also note that this modem is known for having issues with Astound Broadband (RCN, Grande, or Wave) and Optimum. So avoid it if you have either.
Motorola MB8600 Specs
|Type||Cable Modem (No Wi-Fi)|
|Standards||DOCSIS 3.1 & DOCSIS 3.0 32×8|
|Top WAN speed||6000 Mbps|
|Ports||1 open and 3 masked 1G Ethernet LAN & 1 × Coax|
|Top internet plan supported.||2000 Mbps|
|Supported ISP’s||Armstrong, Atlantic Broadband, Comcast Xfinity, Charter Spectrum, Cox, Mediacom, Midco, Suddenlink, WOW, Sparklight|
|Not supported ISP’s||Astound Broadband (RCN, Grande, or Wave), Optimum|
|Dimensions||7.25 × 2.25 × 7.88 inches|
If you want more details, check out the official product data-sheet.
Performance – 4.6
The Motorola MB8600 performed well throughout testing. It reached the 800 Mbps of my internet plan consistently, even during busy hours.
I also performed tests with different internet plans – specifically 100 Mbps, 200 Mbps, and 400 Mbps. It didn’t have any problems with them.
The modem has a standard speed of around 1000 Mbps, constrained by its 1G ethernet port.
You could, however, use this modem with internet plans up to 2000 Mbps. This is because the Motorola MB8600 has something called Ethernet aggregation (or Port Bonding as it’s also called). 
This feature will allow you to combine Ethernet ports into a single data stream that can reach 2000 Mbps.
That said, ethernet aggregation is not that useful today. As few ISP’s offer any cable internet plans that exceed 1000 Mbps.
This does, however, make the modem future-proof for an increase in speed.
I should also note that the other three ethernet ports are masked. Meaning you can’t use it for your devices. Even though you shouldn’t have to either since you will most likely have a router for that. 
The Motorola MB8600 also held a solid connection throughout the entire four weeks. Without any drops or other problems.
Overall, the Motorola MB8600 performed very well and had no issues.
Design – 4.4
The design of the Motorola MB8600 is very standard. It’s a rectangular box with the dimensions 7.25 × 2.25 × 7.88 inches. Which isn’t large, but still a bit bigger than the Arris Surfboard SB8200, for example.
The backside has three observable inputs. These are the ethernet port, the coax port, and the power input.
But don’t be fooled by this. Because the Motorola MB8600 has three more ethernet ports hidden behind the yellow label. Which can be lifted using a paper clip.
It also has five lights in the front. One for power, two for downstream and upstream channels, another for internet access, and the last for the LAN connection.
My only point against these where that they were a bit bright. So I could imagine that it might be annoying if you sleep in the same room as you have the modem.
Overall, I found the design pretty average. Even though it wasn’t really anything wrong with it, except maybe the lights.
Compatibility – 4.5
It’s always very hard to know exactly which cable modems will work with which ISP. As I can’t test every ISP all over the country.
However, I have done plenty of research for which modems will work where when I put together the approved modems hub. So I have a pretty good idea of which modems are supported by which ISP.
Thus, here are all the ISPs that the Motorola MB8600 is approved for (i.e. will work for), and all the ISPs which it has issues with.
- Breezeline (Atlantic Broadband)
- Comcast Xfinity
- Charter Spectrum
Known for having issues on
- Astound Broadband (RCN, Grande, or Wave)
The modem should also work with any other ISP, Which neither has approved the MB8600 nor is known for having problems with it. That is as long as you have cable internet and not DSL or fiber internet.
Still, I would recommend you to call your ISP and ask, just to be on the safe side.
Moreover, the modem might actually work for RCN and Optimum in some areas of the US. If that’s the case for you, please share that in the comments below.
Setup – 4.8
The setup of the Motorola MB8600 was as simple as it gets. With clear instructions and that were easy to follow.
To summarize it, it goes like this: [3, 4]
- Connect the coax cable and the power cord to the cable modem.
- Turn it on and wait until the second green light from the ground turns green.
- Connect it to your router or PC using the LAN port. Make sure both the modem and the router are turned off.
- Then, to activate the cable modem, you can either call your ISP and give them the MAC address (found under the modem). Or activate the modem online using your ISP’s activations page.
Here is a Youtube video I found which shows the entire process very well.
Note that you will not get a Coax cable with the modem. If you currently don’t have one, you need to get it separately.
Furthermore, you can also access the modem on its IP address, which for this modem is 192.168.100.1 (the same as the MB8611). There you can find the modem status and logs. 
Value – 4.6
The Motorola MB8600 is, in my opinion, one of the most value-packed DOCSIS 3.1 cable modems on the market.
What stops me from giving it a higher score is that not everyone reading this needs a DOCSIS 3.1 modem.
Because if you have an internet plan that is slower than 1000 Mbps, and your ISP doesn’t require a DOCSIS 3.1 modem – then you don’t need one.
What modem you need is decided mostly by your internet plan. A faster internet plan requires a better modem.
That said, even if you don’t need one, I still think that a DOCSIS 3.1 modem could be a better value option, but it depends on your circumstances.
Because a DOCSIS 3.1 modem will future-proof your internet for any speeds increases or an update in your ISP requirements.
This is why it likely will be cheaper, in the long run, to get a DOCSIS 3.1 modem instead of a cheaper option.
Yet, if you are switching to fiber in a year or less, you might want to get a slower modem. So it really depends on your circumstances.
Motorola MB8600 Reviews
After reading plenty about the Motorola MB8600 online, my view is that the modem seems to work very well for most people. But it does appear to have some defective units.
The thing is, I’m yet to find a cable modem that doesn’t. And honestly, I’m always unsure if it could be some other reason involved with the problems.
Motorola also has a two-year warranty to combat these problems. So if it happens, you can get a new one.
Some also complained that it didn’t work for DSL or fiber internet. Which of course will be the case as it’s a cable modem.
So, overall most people (me included) liked the Motorola MB8600. With a lot of emphasis on its speed and simple setup.
Even though the Motorola MB8600 is a good option, you might also want to consider some other modems.