The internet is an opportunist. It can travel by radio waves, phone lines, cable networks, and even the electrical wiring in your house.
For now, most data travels between computers using physical wires. Cable, DSL, and Fiber are the most common type of wiring that carries internet service.
DSL vs Cable Vs Fiber Overview
Fiber internet connections deliver faster download and upload speeds than DSL and cable, usually 250–1000 Mbps. Cable and DSL deliver download speeds in the 25–500 Mbps range. However, cable and DSL upload speeds are normally much lower, in the 5–30 Mbps range. Fiber may be priced a bit higher, but the service is more reliable.
The primary difference between cable and DSL is that cable uses newer “coaxial” lines, which can carry more bandwidth. DSL uses older telephone lines. DSL speeds usually cap out around 25–100 Mbps, which is about half the normal speed range for cable internet. However, DSL providers often build fiber lines closer to residences in urban areas, which results in faster maximum speeds.
DSL vs Cable vs Fiber Speeds
DSL vs Cable
The choice between DSL and cable is common in the US, since most homes are wired for both. DSL is lower-bandwidth and comes over the phone line, with maximum speeds rarely exceeding 100 Mbps. In urban areas, DSL may be faster due to using “Fiber to the Node” infrastructure to reduce the distance of the low-bandwidth copper telephone line, which is used to connect carrier fiber lines to customer homes.
Cable vs Fiber
Fiber is a common upgrade choice from DSL, particularly in larger cities. Fiber is the best choice for most customers, as it provides high-bandwidth connections up to 1,000 Mbps download and upload speed. The difference between cable and fiber is that cable is sent over copper TV lines, while fiber is made of plastic and designed specifically for internet service.
Landline telephone lines (DSL). DSL utilizes your telephone lines, but it doesn’t interrupt your phone use. It’s a step above dial-up internet, but it’s still the slowest of all other modern options. DSL vs. cable internet isn’t much of a competition. Examples of DSL plans include CenturyLink’s 20 Mbps internet-only plan.
Cable TV lines (cable). Cable internet reaches your home through the same coaxial cables that your TV service likely uses. It also offers an improved connection speed over most other internet options. One major perk is that it is widely available — unlike fiber internet. Examples of Cable plans include Spectrum’s 100 Mbps internet-only plan.
Fiber-optic lines (fiber). Fiber optic cables are a truly impressive development for data transfer. Fiber internet utilizes these optic lines that are made of many small fibers of glass. With this method, data is actually sent at the speed of light, since it is not electricity that is being sent through the lines, but light. Unfortunately, fiber internet isn’t readily available. Examples of fiber plans include AT&T’s gigabit internet service.
DSL vs Cable vs Fiber: Speeds Overview
For help understanding what speeds you need for different activities, see our bandwidth calculator or our guide to how much internet speed you need.
Here is a general speed overview of fiber, cable, and DSL internet service:
Fiber optic internet speed: Fiber optic internet speeds are the fastest available.
Cable speed: Cable internet speeds are very fast and can rival fiber’s download speeds. The downside to cable vs. fiber internet is that upload speeds can’t reach the same highs.
DSL speed: DSL internet speeds are the slowest and usually max out around 35 Mbps. A DSL vs. fiber comparison is almost not worth making as fiber can reach speeds 400 times faster than DSL.
DSL vs Cable vs Fiber: Which Is Best?
Here’s the big picture on the DSL vs cable vs fiber dilemma:
Here’s the big picture on the DSL vs. cable vs. fiber dilemma:
DSL is best for rural customers who otherwise are stuck with satellite internet.
Cable internet service is the best choice for people who don’t have access to fiber or have no use for lightning-fast speeds. It is also a great option for TV-viewers who can benefit from cost-cutting “cable bundle” plans.
Fiber is the best option for heavy internet users, especially for gamers or those who plan to stream videos on multiple devices simultaneously.
If you feel there aren’t enough internet options in your area, you aren’t alone. If cable or fiber connections aren’t available to you yet, know that services are expanding every year. In addition, new technologies such as next generation low Earth orbit satellites may soon be able to provide robust connections to rural consumers. Hopefully, within the next few years, high-speed internet will be nearly universally available.
How Do Internet Service Connections Work?
It’s difficult to visualize the internet. (See The Internet Mapping Project for amusing examples of people attempting to draw what it might look like.)
To understand where the internet is coming from, you can imagine it as a tree. Your neighborhood is a twig, and the core of the tree is the “backbone.”
The “Internet Backbone is Made of Fiber Optic Cables”
The backbone of the internet (the part that transmits data between cities, countries, and continents) is mostly made of fiber-optic cables. These networks are sprawling and complex. The main thing to understand is that they’re basically bundles of fiber-optic cables that carry data over huge distances — across continents, and under oceans between them.
Consumer Internet Companies Are “Last Mile” Providers
DSL, cable, and fiber connections all have one thing in common: connecting consumers to the “backbone.” For this reason, internet services sold from ISPs to consumers are called “last mile” technologies.
Even with a lowly dial-up connection, most of the journey data travels between your computer and servers happens over fiber on the internet backbone or carrier fiber networks.
However, those last couple miles between your house and the ISP can slow things down considerably, because the data switches over to older copper cables.
So, what does this mean for the consumer? Well, DSL internet has a few advantages and disadvantages in comparison with cable and fiber.
The main selling point of DSL is widespread availability; telephone infrastructure is already deployed basically everywhere, so it doesn’t take much setup to get most folks connected by DSL, especially in rural areas where cable is less likely to be an option.
The second advantage is in how the connection reaches the end user: while cable connections are essentially shared within neighborhoods, DSL connects directly from ISP to consumer.
While cable provides faster speeds, it can get bogged down at peak times (e.g. 6-9pm, when everyone in the neighborhood wants to stream Netflix while their kids broadcast on Twitch upstairs). Because of this, the DSL connections can seem more consistent, even if they are overall slower than cable.
The big downside of DSL is the phone cable itself; telephone cables usually top out at around 40 Mbps down, while cable can deliver closer to 100 Mbps under ideal conditions. (However, shared bandwidth and unmaintained infrastructure often results in equivalent effective speeds for either technology much lower than 40 Mbps).
Distance between ISP office and residence is also a factor with DSL connections, as residences farther from the central office generally receive slower speeds and higher latency than those closer to the office.
Because telephone cable is thinner in diameter than coaxial television cable or fiber, it requires “repeaters” every couple miles to keep the signal from degrading more than 3-5 miles from the ISP office where the fiber “backbone” meets the copper “last mile.”
Cable solves some of the problems associated with DSL service (low bandwidth, outdated infrastructure) but comes with its own host of potential failure points.
The biggest con when it comes to cable is higher cost, largely a product of lack of competition among cable providers — cable infrastructure is more expensive than telephone, so many Americans only have access to one provider if they want true broadband internet.
The other problem point with cable is bandwidth sharing. Since bandwidth is shared within neighborhoods, oftentimes cable will be slowed to the same speed (or lower) than DSL during peak use times.
From the consumer’s perspective, fiber’s big advantage is simply speed and resilience. Fiber is by nature unaffected by electromagnetic interference like copper, making it much more resilient to outside factors — like proximity to other infrastructure and weather.
Overall, fiber has few faults outside of cost and limited availability. For the time being, it’s the most advanced form of data transmission available (outside quantum internet) and represents the future of internet access in the developed world.
The Takeaway: Fiber Is King, but Isn’t Widely Available
While fiber has yet to become readily available to consumers on the same scale as cable and DSL, it’s already the dominant internet infrastructure from a “big picture” perspective. It handles the majority of data traffic outside the “last mile” familiar to broadband customers.
The internet is a “network of networks,” and the mix of types of internet connections will likely be a part of our society for years to come.
We can expect that fiber will continue to grow to the point that it will, one day, be as available as cable internet. As our society increasingly relies on high-speed internet, the thirst for faster internet will likewise grow.