Motorola SB6121 Product Details
The Motorola SB6121 delivers your complete personal media experience, at incredible broadband speeds. It harnesses the power of DOCSIS 3.0 technology to bond up to four downstream channels and four upstream channels. As a result, providing you advanced multimedia services with download speeds up to 172 Mbps in each direction. That makes surfing, shopping, and downloading far more realistic, faster, and efficient than ever before.
Motorola’s easy-to-use SB6121 SURFboard DOCSIS3.0 Cable Modem unlocks the potential of offering innovative high-bandwidth data and multimedia services to customers.
The Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem provides operators with an economic option for providing Ultra-Broadband services. This powerhouse modem competes on both price and function with four times the current maximum data throughput of around 160 Mbps. Maximizing an operator’s current infrastructure investment, the SB6121 can be deployed without service interruption.
Backwards compatible to DOCSIS 1.0, 1.1 and 2.0, the SB6121 also supports both IPv4 and IPv6, Advanced Encryption Services, and all other DOCSIS 3.0 standards. As part of Motorola DOCSIS 3.0 Ultra-Broadband family of products, the SB6121 includes an enhanced tuner that supports up to a 1 GHz downstream input, which allows operators to increase the frequency spectrum for deployment of new high-value services, such as bandwidth on-demand, commercial services, interactive gaming, and IPTV, to their customers.The SB6121 features a 10/100/1000Base-T Ethernet (RJ-45) port, as well as intuitive, easy-to-read status LEDs. Customers can optionally activate dual colored LEDs to have visual verification of bonded channels and GigE use.
Key Motorola SB6121 Features
- 4X Faster than DOCSIS 2.0
- Download speeds up to 172 Mbps
- DOCSIS 3.0 Cable Modem
- 4 download & 4 upload channels
- Supports IPv4 and IPv6 – the latest Internet standard
- Compatible with all U.S. Cable Providers
- Gigabit Ethernet Connectivity
Please note that this model is a modem only, with no built in WiFi. Therefore, If you need wireless internet, a WiFi router will need to be purchased separately.
Phil Stracchino (Technical Thug) –
Motorola’s SB6121 cable modem is one of the best cable modems available on the market right now, if not THE best. It is a full DOCSIS-3.0 modem, but also fully backwards compatible with DOCSIS 2.0 and all the way back to DOCSIS 1.0. In short, it should work on any cable system. It is future-ready with IPv6 support built in.
I bought the SB6121 to replace a D-Link DCM202 which had started randomly dropping the connection several times a week, sometimes multiple times a day. Installation is trouble-free; just connect the cables and notify your cable company. (Have the MAC address from the label on the bottom of the modem handy when you call.) Many cable users report speed gains on updating to a DOCSIS 3.0 modem; I’m no exception — my download speed went from 11.5Mbps to 12.8Mbps, and my upload speed increased by 50% from 960Kbps to 1.5Mbps.
Interface-wise, there’s not a lot to say. The Motorola SB6121’s colored graphical-icon LED indicators are much easier to identify and read from a distance than the D-Link’s closely spaced row of identical yellow-green LEDs. You can look at it from across the room and see two steady blues and one blinking amber, and know at a glance you’re in good shape.
This is perhaps a more expensive modem than some, but it’s worth it, and you can’t fault Motorola’s reputation. It also carries a better warranty than many other cable modems. Do yourself a favor and buy this OEM-packaged version; the shinier box on the retail version won’t make your cable connection any faster. (But the chances are good that this modem will.)
UPDATE, June 2017: Five years on, this modem is still going strong. I had a network problem recently that I thought was the modem’s fault, and tried replacing it with a SB6141, but that didn’t solve the problem. Six weeks of troubleshooting with my ISP later, after replacing the drop to the house, they identified and fixed a fault in the hard-line on our street. Once that was fixed, the SB6141, ironically, DID have a problem that is causing it to drop the connection every 11 days or so … so I’m switching back to the SB6121.
A. Marklin –
Preliminary review based on just 48 hours experience; I’ll update later to address connectivity and longevity aspects.
My ISP is Mediacom Cable, and I’m paying for the best residential Internet package currently available, 15Mb/1Mb speeds (I know…we’re backward here–they are rumored to be releasing 50M/5M speeds in 2013). I had their standard RCA DOCSIS 2.0 residential modem, but they recently began charging $5/mo for it, so I needed one of my own, and wanted DOCSIS 3.0 for the future.
With the RCA modem, the best I could achieve was 14.5Mb/1.5Mb, and usually 9-12Mb down was more typical.
So I ordered this OEM Brown Box model SB6121, plugged it in, and called Mediacom to register the MAC address. Initially had some trouble with the tech getting it connected (think she mis-typed the MAC), but it finally did after about 10 minutes, and I had an Internet connection–but speeds were extremely slow. Power-cycled the modem and waited for it to connect, then rebooted the Netgear WNDR4500 router and everything was fine.
The Motorola 6121 gives me speeds of 28-30Mb download and 2.5Mb upload, so the modem apparently bonded two circuits automatically. Still paying for the same package, but getting twice the performance.
I replaced the basic Time Warner modem with this one after Time Warner started to charge a rental fee. To be honest, I didn’t mind the old one, but on principle was not interested in letting TW nickel and dime me.
The old modem would seem to slow down and stutter at times while streaming movies, which I attributed to being on the lowest cable speed plan available which was 10mbps. This made a Roku box I bought and returned literally useless because it was always freezing up. Streaming onto a computer was better, but still annoying at times. In-fact I was planning on switching to a higher speed plan from TW to end this issue. With this modem, my connection is completely stable and in addition is much faster. With the old modem, my download speeds from Microsoft’s servers would top off at about 1.3 MB/sec, but now I get consistently 1.9 to 2 MB/sec. If I had known what a piece of junk my old TW modem was, I would have replaced it from the start with my own modem, even without the incentive of avoiding another junk fee/rental fee.
I bought this modem even though it was overkill for me because I was thinking about upgrading my connection.
When I was shopping for my modem, I was trying to decide between the SB6121 and the SB5101U which Amazon has for $50. I went with the SB6121 because I was planning on upgrading my connection speed because I was blaming it as being to slow for my heavy use, but looking back, the SB5101U may have been just as good for my needs
Bill Oakes –
I recently upgraded my internet service, and my old DOCSIS 2.0 modem would no longer cut it. With the new service, I was capping out at 30mbps. Nice, but not the promised land. After doing a search and reading reviews, I pulled the trigger on the Motorola.
I received it the next day (LOVE Amazon Prime!) and opened it up. As the description says, this is about as basic packaging as you can get. Just the modem, a cable, and a one page instruction sheet. That said, that’s pretty much all you need. I plugged it in, went through the automated registration with the local cable company, and BOOM. Up and running, 65mbps! (six years ago, I was struggling to get 600kbps over DSL….the world has definitely changed for the better!).
The front of the modem is VERY straight forward….four lights….on, send, receive, traffic. That’s all she wrote. And again, all you need.
Definitely a good DOCSIS 3.0 modem at a great price.
Mark A. Corliss –
I bought this cable modem because Comcast upgraded their system. I wanted to avoid renting their cable modem because the last one they gave me looked funky, and was so light the cable going into it wouldn’t allow it to sit on my desk properly. This unit is also too light to resist the cable coming into it, but at least it sits uplight without tipping over constantly. I have noticed that it runs hot, and I’ve had a handful of bandwidth “events” since installing it. Unplugging the modem, and my Apple Extreme wireless device, waiting a few minutes, then plugging everything back in seems to deal with that problem. I’m on the end of a cable line, with neighbors who are heavy file-transfer users, so I guess I have to accept that. I’m concerned that the temperature is going to damage internal components quickly. If I have to replace this unit within the year, I will never buy another Motorola Cable Modem again.
Philip Reese –
I have bought four of these over the past three years – all for different installations. All have been rock solid, only needing to be reset once every few months. Compared to the various routers we’ve had hooked up to the modems, the modem is very solid and reliable. I’ve recommended this modem to multiple friends and each has purchased one and been pleased with it.
If Comcast is your ISP, this modem is compatible. It’s certainly good for others, but Comcast is all I’ve tested with. Sample data rate below.
On my 50mbps connection I see 57mbps downstream; the modem clearly isn’t holding me back.
Lovely Lily –
Best answer to a troublesome cable vendor who cannot offer the features you have to have to implement certain solutions like VOIP. This passthrough modem was easy to install. Plug it in and you’re done. You will have to go through some kind of activation on the cable company side. But after that, plug your firewall device into the modem and enjoy a hassle free cable modem. Course, your cable vendor will not be able to help you with the modem, but that is the beauty of it. Ahh.. no 3 hour phone calls with #%#* cable providers. Sweet.
Irwin Electronics –
It always happens, frequent disconnects, dropped pings, reduced speed, frequent router reboots… The cable company says there is nothing wrong. Yes, there is. You are using their modem! Send back their refurbished, used, and abused POS, and buy a GOOD modem! If you continue to have trouble buy a good TP-Link router. If trouble persists, NOW you can safely blame it on your Internet Provider. Most likely, with this set-up, your Internet connection will be solid. These Motorola modems are the best in the business. Take it from me. I used to work for a couple cable companies years ago. I am a Microsoft Certified Systems Engineer, and now own my own computer repair business. I help get my customers connected all the time. I have never received a 4 star review. I know what works. These modems work!
These old work-horses are the energizer bunnies of cable modems for years now. I am a retired tech. life time of electronics and will still pass on the newer stuff over these. Just put in another today and on a mile and a half of copper from a fiber feed, it did an honest 103mb down and 10 up
10mb up is the ISP throttle , not the modem) that was ‘after work’ peak, not unusual for a solid design manufactured using older tech. I have several very old (and battle scarred 6121’s that work as well. Save $ here and buy a much better router, You will thank yourself in the long run.
I purchased this to install in a structured wiring cabinet. I needed it to replace a much larger cable modem. I found that it locked up at least once every other day. I’m not sure if it is a firmware issue or compatibility with my local cable company. Either way, I threw it in a box and have it stored in the garage. This did not work well for me.
GREAT MODEM. MONEY SAVER.
Easy to set up. Three simple steps. Not so easy to connect. I was replacing my existing modem and had to contact my provider to register the information on the bottom of my new modem. I suggest you copy the information on the modem before you connect the 3 wires. You will need the info and hard to read after connecting. WORKS PERFECTLY.