Troubleshooting Q&A - June 7, 2005
Are Cable and DSL Created Equal?
Both broadband technologies have matured over recent years and are faster, easier to setup and more reliable. Each has its pros and cons, but which is better? The answer is a frustrating 'it depends.'
By Ron Pacchiano
Q. After months of begging and pleading, my folks have finally agreed to let me get a broadband Internet connection. Now that I have their permission, I need to decide which connection type I want to go with: Cable modem or DSL. Some of my friends have cable and some DSL, but both claim to have the best connection. Needless to say, I'm pretty confused. Prices seem to be almost identical, so that's not really a factor. I was hoping to get your opinion on the subject. Which do you think is the better broadband connection?
A. I can't tell you how many times this question comes up. The truth is I don't think that you can necessarily say that one is better then the other. Over the years, both technologies have matured and both have become faster, easier to setup and ultimately more reliable. Each has its advantages and disadvantages, so it really comes down to what's available in your area and what you feel more comfortable with.
Generally speaking, cable can support higher bandwidth rates and can usually provide service to a larger area than DSL's 18,000 wire-feet limit. This limitation has been a big frustration to many potential DSL users. One guy would sign up for DSL service, but his neighbor one block away couldn't because he exceeded the 18,000-feet limit. Check DSL availability in your area to see if it's even an option for you.
To get cable modem service, you just have to have cable access in your home. You usually pick up the hardware right from your cable provider and install it yourself. So getting it up and running is quick and usually easy. To get DSL service, however, your phone line needs to be provisioned by the phone company. This can take several days, and sometimes even weeks, to accomplish. From what I've heard, though, this process has gotten much better. It still takes longer than cable, but generally, no where near as long as it used to.
Cable modems are also typically faster for downloads than most, if not all, DSL lines. When the cable infrastructure is new or well-maintained. However, DSL is no slouch in the speed department either. These days the typical DSL residential offerings usually have a maximum data transfer rate of 1.5Mbps (1.5 megabits per second). Realistically, though, 1 - 1.2Mbps is what you can expect to see.
Lastly, cable companies usually let you use their service on a month-to-month basis. Most of the DSL companies that I know of (like Verizon, for example) require you to sign up for at least a one-year contract. If you have a problem with the service for any reason, you're stuck with it until your contract is up or you pay an expensive termination fee.
Now let's recap, cable modems have a larger service area, can be implemented quicker, typically offers its users faster download speeds compared to DSL and doesn't require you to sign up for any long term contracts. Does this mean it's better? Not really.
Cable isn't perfect. To begin with, cable is an RF network this means that it is vulnerable to transient problems "within the network" from RF interference. This is especially a problem for upstream or "return path" bandwidth. More and more applications have appeared (like online gaming, video conferencing and even file-sharing services) that need a strong upstream channel. Cable companies are using a very narrow band for return signaling, and this is positioned below all the space allocated for TV channels. This band is prone to RF interference and is very limited in capacity. Upstream transmissions may therefore compete with others in the area, get delayed (suffer high latency) due to noise fighting techniques, and most cable companies Terms Of Service (TOS) typically prohibit any kind of constant upstream usage.
Also, since cable is a shared media, there is a possibility that network performance may degrade over time as additional households plug in and connect more and more devices to the network (ex. DVR, Xbox Live systems, etc.). The cable company might also react slowly to decreases in performance (if it even reacts at all) as they never sell access by speed, or promise of consistent speed or latency.
In most cases, DSL's dedicated circuit prevents other users from affecting your connection to any significant degree and should give you a relatively consistent upstream rate at all times.
Speaking of which, one of the biggest complaints that most people have with cable modem networks is this perception that it is a shared network and that DSL is a dedicated line. While it's true that DSL is giving you a dedicated circuit, it is still part of a shared network. DSL service shares bandwidth amongst ALL users connected to the same DSLAM (Digital Subscriber Line Access Multiplexer) while cable shares bandwidth amongst ALL users connected to the same CMTS (Cable Modem Termination System) . So bottom line, both are technically shared services, they're just being implemented differently.
In summary, cable modems are currently a good value and strong competition for residential casual use, are often very inexpensive and are, on average, far faster than their DSL competition. However, DSL is probably the more future-proof system, offering digital direct from the Internet infrastructure. If your DSL ISP is on the ball, your performance in either direction will not be different from peak hour to early morning. So again, it really comes down to what you feel comfortable with. Personally, I have had both and right now use a cable modem for my Internet access. It's been very good, highly reliable and continually gives me speeds quicker then a T1 line. For the moment, I couldn't be happy with it.
Regardless of which broadband connection you decide upon, just remember to get yourself a good router/firewall and anti-virus application to protect your PC(s) while you're online. The speed of a broadband connection is very appealing, but it does expose you to a lot of potentially dangerous situations. Make sure you're protected. Good Luck!
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