What modem for my new router

Technology QuestionsCategory: NetworkingWhat modem for my new router
AvatarJaggery77 asked 6 years ago

Hey marcel,
i love the router knowledge and all. So I plan to update my router based from your good info but I didn’t seem to find a good article defining what my modem should be if my isp internet is 100 mps or 75 mps through fxfinity. We’ve had horrible servivce and switched to my own gear but it’s not going great and I have a gen 2 airport express needing to update but I wondered what you’d recommend if my cable modem I already own is a arris sb6121. DOCSIS 3.0 certified, capable of up to 172 Mbps and upload speeds up to 131 Mbps based on Cable Internet Service Provider
Supports IPv4 and IPv6 networking, as well as Windows, Mac, and Linux computers
10/100/1000Mbps Ethernet port to connect with router or computer. 4 channel if I’m right. That’s what I got. Currently we have 75mps service but might go to 100. We don’t have fiber here yet besides xfinity and I can’t stand there CS. So I’m waiting to go back to att fiber even with your great article about the caveats explained some cons. So if I’m upgrading my router what modem do I get or what article or info to point me to what I need to go with my new router unless you think the modem I have is enough? I just here that it sounds like it’s better to have a little more ability of modem within reason of course. Same with routers and not buying overboard. So knowing what speeds I’m getting through isp and with what modem I have. What do you think about what I have for modem and what specs or features should I look for if it were you? Thanks for your time and help!

1 Answers
Marcel BrownMarcel Brown Staff answered 6 years ago

If you’re only going to go up to 100 Mbps speeds, then your SB6121 is plenty fine. Since it can support up to 172 Mbps, anything else is overkill. Of course, you should test your service speeds occasionally to make sure you are getting what you are paying for. I’ve seen many examples of a cable or DSL modem start to malfunction, especially if they are more than a few years old. So if your modem needs to be replaced, then I would recommend looking at a model like the SB6141 (up to 343 Mbps) or SB 6183 (up to 686 Mbps) or even the SB6190 (up to 1.4 Gbps), if you think you’ll be capable of getting these types of high speed services in the near future. Might as well buy something that is a little future-proofed, but don’t go nuts if the likelihood of these really high-speed services in your area is unlikely in the next few years.