Does Having Cable and Phone Service Reduce Modem Speeds?DJ Scooby Doo asked at, “I’m wondering if cable speeds are flawed because I have three Time Warner cable boxes; would my speeds be faster if I didn’t have the cable boxes on the same coax split? I also have digital phone from Time Warner and that’s all run through a Motorola modem. So are they flawed if the phone and the TV are taking bandwidth?”

This is an excellent question, and one that I first encountered back in 2001 when I signed up for my first cable modem service. Back then, I didn’t worry so much about bandwidth speeds as anything was faster than dial-up. Today, we are downloading gigabytes of information in minutes rather than hours and having fast Internet service is practically a must.

So does having other services on the same cable line reduce your modem’s speed? Not really, and here’s why:

Cable Space

Think of the coaxial cable leading into your home as a giant roll of sweet tarts. This roll is huge, with literally hundreds of sweet tarts packed into a very small space. Each sweet tart represents a dedicated amount of electrical space, typically sectioned into 6 MHz slots. Each space delivers one channel to your cable box, giving you a wide selection of channels that switch almost instantly as you browse from the couch. Your downstream bandwidth acts like a single channel, only taking about 6 MHz of actual space on the cable. Your upstream traffic works the same way, except that takes even less MHz as it is typically much slower than your downstream.

So does having things like phone and cable on your cable company’s connection reduce the speed of your modem? Not at all. Your modem is treated like any other channel except its data is decoded at a modem instead of a cable box.

Network Congestion

Cable users do have a legitimate concern when it comes to their broadband speed being reduced by outside influences. In a typical cable situation, you are sharing an Internet connection with everyone in your immediate area. Apartment complexes are especially sensitive to this kind of problem, though in this day in age it isn’t as noticeable as it used to be.

If everyone in your apartment complex, neighborhood, or service region suddenly decided to start downloading torrent files while watching Netflix, you might notice a drop in you downstream bandwidth for a moment as the cable company adjusts. This type of network congestion is possible, but not likely as many companies have been improving their services since cable modems first came about.

DSL users, however, don’t have to deal with this type of congestion at all. DSL lines are point-to-point as opposed to point-to-router service found with cable. For this reason, DSL was widely considered the superior of the two technologies. Today, with FiOS and other elements improving the speed and capabilities of these lines, people are seeing incredible speeds in their homes which far exceed previous boundaries.

How Can You Increase Your Internet Speed at Home?

Aside from buying a faster connection from the carrier, there are a number of things you can do to optimize (if not increase) your bandwidth at home.

Replace your cable modem if it’s becoming old and unreliable. Too many people make do with whatever the cable company gives them, not knowing that there is an aftermarket out there that might have better solutions for you. Call your cable provider and ask if third-party equipment is allowed. If so, take a look at cable modems online or at your local electronics stores and compare capabilities. Many service providers offer little to no network hardware, and if they do it’s typically A/G class wireless which is all but obsolete in the Wireless N world we live in today. 10/100 ethernet routers are a common sight among cable provider hardware, though a good 10/100/1000 gigabit router could give you a boost in speeds within your network. Will this translate directly to your Internet speed, not as much as the wireless upgrade might.

Take a good look at your computer. Have you defragmented lately, or taken a moment to update your operating system’s software? Performing occasional maintenance on your equipment will do a lot to improve its perceived Internet connection as it will be able to more efficiently handle the incoming and outgoing data.

Check to make sure you’re not running software that is eating up your network bandwidth. This can be a huge problem for some users in shared networks where your roommate, relative, or spouse might be downloading large amounts of data and essentially hogging what bandwidth you actually have. In this case, it might be a good idea to invest in a network server or router that distributes the connection evenly among users.

You can always call your cable company and ask them to test your connection on their end. This test can help the company identify where maintenance might be needed on their end and dispatch a technician to do so. If you’re having problems maintaining a wireless connection to your modem/router, you might want to ask about having it replaced. Sometimes, your cable company is working with much newer modems than the one you started out with, and switching them out can make a world of difference.

Take a moment to test your Internet connection to see if you’re really experiencing speeds that are slower than you’ve been promised by the provider. is a great tool that I use every time I’m experiencing a slow connection. It’s the best way to quickly determine whether or not a problem you’re experiencing is coming from your connection or other factors that may warrant further investigation.

Your Internet connection is your lifeline to the Web. Cable companies have been providing broadband connections for almost as long as broadband has been possible for consumers. These providers have, in many cases, worked diligently to combat the perception that cable is always slower than DSL. In reality, it’s all about the bandwidth your individual provider can offer and the price you have to pay for it. In many areas of the country, the cable-based provider is actually more reliable than the alternative. Do your homework before settling on an ISP, even if you have had that particular ISP before at another address. You might just discover that even a short distance can make a big difference.

Ethernet Cable by Petr Kratochvil