What is DOCSIS

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Last Updated: May 6, 2022 | Published: Dec 1, 2021

Data Over Cable Service Interface Specification (DOCSIS) has been delivering the internet to homes and businesses since 1997. In a world where technology can become outdated between the time of purchase and the time you get home, DOCSIS has shown that constant, consistent innovation will keep this international telecommunications standard relevant for years to come.

What Is DOCSIS?

DOCSIS is an international standard for transmitting data over coaxial cables. This is the same technology that cable television subscribers have been using to receive programming for decades.

DOCSIS is a telecommunications standard endorsed by the International Telecommunications Union, a specialized branch of the United Nations, and was further developed by CableLabs in Colorado.

How Does DOCSIS Work?

To say it simply, DOCSIS utilizes a cable TV channel to transmit data to and from a modem via coaxial cable. No, the channel isn’t one that you can watch. Instead, it is the channel through which you can receive an internet connection, cable TV, and other services you subscribe to from your cable provider.


DOCSIS Working Architecture
DOCSIS Working Architecture

DOCSIS determines which channel to use to transmit the data and the transmission of said data to and from your provider.

The Evolution of DOCSIS

DOCSIS has come a long way and with good reason: With more people online than ever before, and fiber-optic companies gaining ground, cable companies need to keep their systems fast. DOCSIS should remain around for many years to come, as installing fiber-optic networks would require extensive infrastructure building.

DOCSIS Version Max. Download Speed Max. Upload Speed
1 40 Mbps 10 Mbps
1.1 40 Mbps 10 Mbps
2 40 Mbps 30 Mbps
3 1 Gbps (1000 Mbps) 200 Mbps
3.1 10 Gbps 1 Gbps

DOCSIS 1.0

The first DOCSIS network was released in 1997. It boasted a 10 Mbps upload capacity and 40 Mbps download capacity.

DOCSIS 1.1

DOCSIS 1.1 can’t brag about speed improvements, however, it did have service flow management. This allowed different types of data (voice, video, etc.) to be identified by the modem and treated accordingly, which greatly increased the quality of service.

DOCSIS 2.0

Released in 2002, version 2.0 retained the download capacity of its predecessor, but multiplied its upload capacity by three times with a 30 Mbps speed.

DOCSIS 1.0 and 1.1 are considered obsolete. As cable companies upgrade their networks, modems will become incompatible. That’s just the nature of the beast. Most cable providers have already upgraded their networks to DOCSIS 3.0.

DOCSIS 3.0

As mentioned above, DOCSIS relies on data traveling via a cable television channel. DOCSIS 3.0 made a huge jump up from version 2.0 with the implementation of multichannel bonding. Put simply, multichannel bonding uses multiple channels at the same time for uploading and downloading which greatly increases bandwidth capacity.

In addition to the innovation of multichannel bonding, DOCSIS 3.0 can reach up to 1 Gbps download speed and 200 Mbps upload speed — a large leap from 2.0’s speed limits of up to 40 Mbps download and 30 Mbps upload speed. The speed will fluctuate depending on how many channels the modem can utilize.

DOCSIS 3.1

DOCSIS 3.1 is 10 times faster than its predecessor; it has 1-2 Gbps upload capacity and 10 Gbps download capacity.

While you think that you don’t need anything that fast, keep in mind the nature of technological evolution: what’s cutting edge today can become obsolete tomorrow. You might as well spend a little extra now to ensure your equipment will be compatible for a number of years; otherwise, you may end up shelling out more once that equipment is no longer viable, and sooner than expected.

What to Look for When Buying a Modem

Before you go out and purchase the most expensive, multichannel DOCSIS 3.0 or 3.1 modem you can find, know that your options may be limited based on which plan you have.

If your plan is anywhere from 150 Mbps to 1 Gbps, a DOCSIS 3.0 modem won’t disappoint. That said, there are cable providers that require you to use a 3.1 modem for certain plans. Do yourself a favor and check with your provider before making a purchase. Providers often have a list of compatible modems online.

We recommend the Arris Surfboard SB6190 if you’re looking for a DOCSIS 3.0 modem.

DOCSIS 3.0 Modem
DOCSIS 3.0 Modem

The Arris Surfboard SB6190 is a great example of a DOCSIS 3.0 modem. It can handle 1.4 Gbps, and comes equipped with 32×8 channels (32 download; 8 upload). It is also compatible with most major cable providers’ networks: Xfinity from Comcast, Spectrum, and Cox.

It is available for purchase through Arris, Amazon, and Walmart for about $70-$100.

For a DOCSIS 3.1 modem, we recommend the Motorola MB8600.

DOCSIS 3.1 Modem
DOCSIS 3.1 Modem

The Motorola MB8600 is one of the best DOCSIS 3.1 modems on the market. Just like the Arris, the Motorola 8600 is equipped with 32×8 upload-download channels, but this modem can handle download speed up to 3.8 Gbps and gigabit (1000 Mbps) upload speed.

It is available for purchase through Amazon, Motorola, and Best Buy for prices ranging between $130-$160.