DOCSIS 3.0 vs 3.1: Which Modem is Best for You?

Rosslyn Elliott

Written by Rosslyn Elliott - Pub. Nov 17, 2023 / Updated Mar 18, 2024

Are you happy with your Internet service?

Rosslyn Elliott

About the author

Rosslyn Elliott

Rosslyn Elliott has over a decade of experience as a writer, editor, and in-house journalist. She earned a B.A. in English from Yale University and has written professionally in many fields including technology and IT. She has won kudos for her work helping tech startups establish their brands. Having lived all over the USA, Rosslyn has first-hand knowledge of the strengths and quirks of top internet service providers. She now writes on all things internet, including Wi-Fi technology, fiber infrastructure, satellite internet, and the digital divide. As a TV fan, she also enjoys reviewing channel choices and cool gadgets for satellite TV and streaming services. Her personal experience as a researcher, career changer, and remote worker inspires her to guide others to their own online opportunities. After work, she likes to kick back with a good craft beer and speculate about A.I. with friends.

Which speed do I need?

Tell us what you use Internet for

How many users?

Online Gaming
Smart Home Devices
Streaming Video
Browsing & Email

Target speed: 50 Mbps

With multiple users in the house, you need a little wiggle room in your bandwidth. 50 Mbps will support all your web browsing and social media.

Your current Internet speed:

Speedcheck

Find 50 Mbps Internet speed near you

DOCSIS 3.0 vs 3.1: Which Modem is Best for You?

Choosing a DOCSIS Standard for Your Cable Modem

Wondering if it’s time for a new modem? Choosing the right DOCSIS standard for your cable modem is important for your online activities. Your DOCSIS standard determines the maximum internet speeds you can get.

DOCSIS 3.0 and DOCSIS 3.1 support different speed tiers offered by cable internet providers.

With 3.0, you are limited to plans below 1 Gbps, while 3.1 unlocks gigabit speeds up to 10 Gbps. As cable companies roll out faster plans, your modem will need to be compatible to take advantage of the speed boosts.

What is the DOCSIS Standard?

DOCSIS (Data Over Cable Service Interface Specification) is a telecommunications standard that supports high-speed data transfer over existing coaxial cables originally meant for cable TV. DOCSIS allows cable operators to provide broadband Internet access (in addition to TV service) without having to install new fiber-optic lines into homes.

DOCSIS works by transforming the analog video signal on the coaxial cable into IP data. Your cable modem decodes this signal to extract the IP packets and send them to devices on your home network.

 

DOCSIS button on a computer keyboard

The Evolution of DOCSIS Standards

The DOCSIS standard has gone through several iterations. Internet speeds listed below are maximum potential speeds for each DOCSIS standard. Actual speeds will vary depending on your internet plan.

StandardYearNew features introducedDownload speedUpload speed
DOCSIS 1.01997First DOCSIS standard40 Mbps10 Mbps
DOCSIS 2.02001Supports gaming/streaming40 Mbps30 Mbps
DOCSIS 3.02006Support for IPv6*1 Gbps100 Mbps
DOCSIS 3.12013OFDM modulation, low latency10 Gbps1 Gbps
DOCSIS 4.02024Symmetrical streaming10 Gbps6 Gbps

 

*IPv6 (Internet Protocol version 6)  is a more advanced networking protocol that uses 128-bit IP addresses instead of the 32-bit IP addresses of IPv4.

Each new version maintains backwards compatibility with older DOCSIS equipment.

Technical Improvements in DOCSIS 3.1

DOCSIS 3.1 introduces major technical upgrades over DOCSIS 3.0:

OFDM Modulation

DOCSIS 3.1 uses OFDM (Orthogonal Frequency Division Multiplexing) instead of traditional QAM modulation. OFDM packs data more efficiently across a wide spectrum of frequencies, increasing throughput. (Throughput is the actual speed that data passes over a network.)

Low-Latency DOCSIS

Specialized low-latency OFDM channels reduce buffering delays, providing the best support for real-time apps like online gaming, voice calls, and live streaming.

Extended Spectrum

DOCSIS 3.1 can use frequencies all the way up to 1.2 GHz, far wider than the max 860 MHz for DOCSIS 3.0. More bandwidth means higher speeds for your data.

 

children playing with a game system and games controllers

Smoother gaming

Performance: DOCSIS 3.0 vs 3.1

Thanks to these technical improvements, DOCSIS 3.1 modem performance far surpasses 3.0:

  • Download Speeds: DOCSIS 3.1 supports gigabit speeds up to 10 Gbps, 10x faster than DOCSIS 3.0’s max of 1 Gbps.
  • Upload Speeds: DOCSIS 3.1 enables upstream bandwidth up to 1-2 Gbps with Full Duplex DOCSIS. 3.0 is limited to 100 Mbps upload.
  • Latency: DOCSIS 3.1 has 60-70% lower latency than 3.0 thanks to Low Latency DOCSIS, improving response times.
  • Network Capacity: DOCSIS 3.1 boosts capacity up to 50% more on the same spectrum compared to 3.0.

Is DOCSIS 3.1 Worth It? Cost-Benefit Analysis

Upgrading your modem to DOCSIS 3.1 only benefits users subscribed to gigabit-tier internet plans from their cable provider.

For standard plans below 1 Gbps, DOCSIS 3.0 modems can easily handle the speeds. The average $150 cost of a new DOCSIS 3.1 modem may not justify the upgrade. If your internet tends to be really slow, then you may want to investigate the causes before upgrading.

However, DOCSIS 3.1 future-proofs your home network. As cable internet speeds steadily increase, a 3.1 modem will be compatible with multi-gig plans. The more data your household uses per month, and the more devices you have connected at once, the more likely it is that you will want to upgrade.

 

multiple devices including smartphone and computer monitor sitting on desks

Multiple devices

The Path Forward: DOCSIS 4.0

DOCSIS 4.0 builds on 3.1 with a major new feature – Full Duplex DOCSIS. This standard will enable symmetrical multi-gigabit speeds up to 10 Gbps download speed and 6 Gbps upload speed.

Other DOCSIS 4.0 enhancements include unified IoT support, Wi-Fi 6/6E integration, and better security. Public release of DOCSIS 4.0 modems is likely to begin in 2024.

Key Takeaways for DOCSIS 3.0 vs. 3.1

  • DOCSIS 3.1 supports 10x faster gigabit speeds than 3.0, but upgrading only benefits gigabit subscribers.
  • OFDM modulation and extended frequencies support higher throughputs.
  • Low-latency DOCSIS reduces buffering for real-time apps.
  • A 3.1 modem future-proofs your home network for faster internet speeds.

 

cable modem in home on counter

Future-proof your modem

FAQs: DOCSIS 3.0 vs 3.1

Does a router work on DOCSIS standards?

No, DOCSIS standards only apply to cable modems, not routers. A router connects to the modem and does not care what DOCSIS version the modem uses. Any Wi-Fi router is compatible with DOCSIS 3.0/3.1 modems.

DO DSL modems work on DOCSIS standards?

No, DSL modems have their own technology. DOCSIS standards only apply to internet delivered by coaxial cable and hybrid fiber-coaxial (HFC).

Is a DOCSIS 3.1 modem compatible with DOCSIS 3.0 internet service?

Yes, DOCSIS 3.1 modems are backward-compatible and will work fine with older DOCSIS 3.0 cable networks. A 3.1 modem will flex down to 3.0 speeds.

Can I upgrade to DOCSIS 3.1 if my provider only offers DOCSIS 3.0 internet plans?

You can use a 3.1 modem, but you won’t see any speed improvement on a 3.0 network. Only upgrade modem if your provider launches gigabit plans over DOCSIS 3.1.

What is the cost difference between DOCSIS 3.0 and 3.1 modems?

DOCSIS 3.1 modems typically cost $150-$200, around $50-$100 more than DOCSIS 3.0 models priced at $100-$150. The premium provides future-proofing. If you’re already paying for a multigig internet plan, you will definitely want a 3.1 modem or even a 4.0 as they begin to hit the market.

 

woman enjoying her internet connection with her devices

Explore Our Most Recent Blogs

Do you want to leave a review for AT&T Internet?

Rosslyn Elliott

About the author

Rosslyn Elliott

Rosslyn Elliott has over a decade of experience as a writer, editor, and in-house journalist. She earned a B.A. in English from Yale University and has written professionally in many fields including technology and IT. She has won kudos for her work helping tech startups establish their brands. Having lived all over the USA, Rosslyn has first-hand knowledge of the strengths and quirks of top internet service providers. She now writes on all things internet, including Wi-Fi technology, fiber infrastructure, satellite internet, and the digital divide. As a TV fan, she also enjoys reviewing channel choices and cool gadgets for satellite TV and streaming services. Her personal experience as a researcher, career changer, and remote worker inspires her to guide others to their own online opportunities. After work, she likes to kick back with a good craft beer and speculate about A.I. with friends.

Which speed do I need?

Tell us what you use Internet for

How many users?

Online Gaming
Smart Home Devices
Streaming Video
Browsing & Email

Target speed: 50 Mbps

With multiple users in the house, you need a little wiggle room in your bandwidth. 50 Mbps will support all your web browsing and social media.

Your current Internet speed:

Speedcheck

Find 50 Mbps Internet speed near you