By Greg Holden
(9/5/00)

In a perfect world, we'd all have superfast, always-on Internet connections that shuttled at least 10 Megabits (that's 10 million bits) of digital data to our computers each second.

In reality, if you want a broadband connection at home or in your small office, you have two choices, a cable modem line or a digital subscriber line (DSL), and neither can really deliver Ethernet-like speeds.  But these technologies do make it possible for you to watch video clips, play video games online, or just surf the Web without drumming your fingers as you wait for pages to load.  What's more, both DSL and cable access are becoming increasingly affordable, especially when compared to T1, T3, or ATM connections, which can cost thousands of dollars per month.

Although DSL and cable services are affordable, several factors affect the quality of your connection, including location (how close you are to your DSL provider), and security (how much the service opens your computer to hackers).  We'll explore these two technologies, dispel the myths, lay out the pros and cons, and help you decide which one best suits your needs.

The Straight Dope About DSL
DSL stands for digital subscriber line, a technology that transforms a traditional phone line into a high-speed digital link to provide homes and small businesses with broadband Internet access.  Thanks to DSL, you can surf faster, host your own Web site, or connect branch offices of a small business.  But because DSL is relatively new, there's a lot of misinformation surrounding this technology.

The Myths

1. DSL is easy to set up because you're using an existing phone line, and you don't need to install any special new equipment to use it.
2. Once you're connected, you have an Internet connection that's as fast as a T1 line--at least 1.5 Megabits per second.
3. Anyone with a phone line can get DSL cheaply.
4. DSL is as safe and as secure as traditional dial-up modem connections.

The Reality

1. It's not so easy to set up DSL.  True, you don't need a special digital line, and if you have the know-how, you may be able to connect your PC to the service yourself.  But most people will need a technician to fiddle with the necessary wiring and installation of the DSL modem.  Part of that fiddling involves installing an Ethernet network interface card (NIC) in your computer and connecting it to the DSL modem.

   Read more in CNET's "Insider's Guide to DSL" and "ISP Buyer's Guide."

2. Another reality check: Except for a lucky few customers, DSL isn't as fast as some companies imply.  Electromagnetic noise (also called crosstalk) generated by other nearby electronic devices can adversely affect DSL performance.  More importantly, your distance from a telco's special switching facility, called a central office (CO), directly affects your DSL connection.  The further you are from a CO, the slower your connection.  And, of course, no matter how fast your connection, you're subject to traffic jams once you get on the Web.  Note, too, that most DSL service is asymmetric--the download speed is faster than the upload speed.  For example, most starter DSL accounts offer 384-Kb/s download/128-Kb/s upload access.

   Check DSL availability and pricing through CNET's Web Services.

3. Cost is another harsh DSL reality.  You typically have to pay $100 or more for installation, from $40 up to $320 per month for access, $100 to $200 for the DSL modem and network card, plus possible service charges if a technician has to come to your premises when your connection goes down or your DSL hardware stops functioning.

   Like any savvy shopper, you need to bargain-hunt.  DSL providers sometimes offer promotional installation packages and deals.  Your DSL company might, for example, throw in the internal wiring and Ethernet card for free.

4. Finally, there's security.  Because DSL keeps your computer constantly connected to the Internet, you may end up with a static (unchanging) IP address --a unique number that identifies your computer on the Internet.  Traditional dial-up services randomly assign you a new IP address every time you log on, so no one can find you at the same place twice.  With an always-on Internet connection like DSL, your computer is vulnerable to hackers who can gain access to your files, drop viruses on your hard drive, or worse.

   Before you sign up for DSL, ask whether your potential provider offers any security measures.  Many DSL providers will assign you a dynamic (constantly changing) IP address if you request it.  For additional security, some companies, EarthLink, for example, include personal firewall software for the Mac and PC as part of the deal.  But chances are you'll have to buy antivirus and firewall software on your own to keep hackers at bay.  See CNET's review of Internet security software for advice on which software package to purchase.

   Remember, too, that an always-on connection doesn't always have to be on.  If your computer is turned off when you're not online, hackers can't get to it.  An even simpler fix is to turn off the DSL modem when you're not surfing.  Some ISPs say this is fine; others indicate it may cause problems.  Ask your DSL vendor before you do anything.  For other tips, check out Steve Gibson's site.

The Truth About Cable
Like DSL, cable technology provides a high-bandwidth, always-on connection to the Internet (often over the same line as your cable TV service) for a reasonable price.  As with DSL, cable Internet service isn't ubiquitous, and many misconceptions abound.

The Myths

1. Thanks to your big-name cable TV company, a cable connection is easy to set up and available everywhere you find cable TV.
2. With a cable modem, you get connection speeds as fast as 27 Mb/s.
3. Cable Internet access is as cheap as cable TV.
4. A cable connection is as safe from hackers as a traditional dial-up modem connection.

The Reality

1. In order for you to get cable, your access provider must physically attach a coaxial cable and a cable modem to your computer, which may mean adding a network card if you don't already have one.  This installation process is often both time-consuming and costly (around $75, although some companies permit self-installation).

   Nor do all areas of the country have access to cable Internet connections.  If your local cable company--which typically holds a monopoly on all services--doesn't offer Internet access, you're out of luck.  At the moment, there's little if any competition among companies providing cable Internet access.

2. You'll probably never get data transfer rates even close to cable's theoretical 27 Mb/s.  For a number of reasons, connection speeds range from 500 Kb/s to 2 Mb/s.  One big factor is that you share that cable line with other local customers.  If you're the only person in your neighborhood online via cable, you may well get that 2 Mb/s.  But as each person logs on, your access speed is divvied up.  If one of your cosurfers starts downloading mammoth files, your performance will degrade further.

   Ask your cable provider how many other PCs share your cable connection and what will be the fastest connection speeds you're likely to get.  And find out if the cable provider guarantees minimum upload/download speeds.

3. It's true, that cable Net access is relatively cheap--as little as $39 per month.  But beware of not-so-hidden installation costs, including a setup fee of around $75 and $30 to $50 for a network interface card.  Sometimes the use of a cable modem is included in the monthly fee, but not always.

   This little piece of hardware can cost $200 to $300.

4. Because you share your cable connection with the people on your block, it's easy for nosy neighbors to peek at your computer files.  One thing you can do right away is disable Windows' file- and print-sharing features.  In Windows 95/98, open the Network control panel, click the File And Print Sharing button, and uncheck the two boxes in the subsequent dialog box.  In Windows 2000, select Start, Settings, and then Network and Dial-up Connections.  Right-click your cable connection, choose Properties, and in the General tab, uncheck the File And Printer Sharing For Microsoft Networks box.

   Like DSL, cable is an always-on connection with a static IP address, which means you're similarly vulnerable to hackers.  That means you should disable Windows' file- and print-sharing features, turn off your computer when you're not surfing, and install some antivirus and firewall software.  Don't forget to also download the latest security patches for Windows, Internet Explorer, and Microsoft Outlook, and make sure everything that can be secured with a password, is.

   What about just turning off your cable modem?  "When the cable modem restarts, it could take the device up to two to three minutes to fully register with the network," says David Langlands, a vice president for 21st Century Telecom Group, a cable provider in Chicago.  Before you turn the modem off, ask your cable provider about any potential problems.

DSL vs. Cable: The Final Analysis
Now that you're familiar with the realities of DSL and cable, it's time to decide which to buy.  Because there are just about as many reasons to choose DSL as there are to choose cable, we've put together the following scorecard to lend a hand.

Security
Any always-on Internet connection with a static IP address is vulnerable to hacker attacks.  It's possible to protect your computer to some extent: you can turn it off, turn off your DSL or cable modem (if your provider says this is OK), keep an up-to-date anti-virus program running at all times, and install personal firewall software.  Or, better still, ask your broadband provider to equip you with a dynamic IP address.

A unique security issue with cable is that the line is shared with others in your area, which makes it easy for a neighbor to snoop around your computer.

DSL opens your computer to similar security risks, according to David Zhu, a senior consultant with X85 (an ASP provider for small businesses) and former network engineer with a regional ISP.  "If your DSL provider does not have its own security measures to prevent hacking and listening to traffic on the network, you are vulnerable, too," he cautions.

Cost
Both cable and DSL monthly access fees get lower every day, and you can find some decent deals by shopping around.  Many providers offer incentives such as a free modem or installation.  For example, the basic HomeOffice DSL package from Concentric Network Corporation gives you 608-Kb/s download and 128-Kb/s upload speeds for about $69 per month, with free installation and hardware, if you sign a one-year contract.  Another Concentric package charges $89 per month for 1.5-Mb/s download and 384-Kb/s upload speeds.  Higher speed DSL service can easily cost $80 or more per month, with some flavors of DSL for small businesses costing several hundred dollars per month.

So far, cable Internet service is often a bit cheaper than DSL: $39.95 per month or less.  In New York City, for example, Road Runner Internet access from Time Warner Cable delivers 2-Mb/s download and 300-Kb/s upload speeds for $39.95 per month if you also get cable TV from Time Warner; $59.95 if you don't.  Installation costs $69 if you have a network interface card; $99 if you don't.

Availability
DSL service originates from a handful of companies, including Covad, NorthPoint, and a number of baby Bells.  However, you typically order the service from your local ISP.

The question of cable modem availability is pretty simple.  Either your local cable company offers Internet access or it doesn't.  However, if you live in a rural area, neither DSL nor cable may be available.

Comparative Tables
Confused?  Don't be.  The following tables recap DSL and cable service similarities and differences.

Table 1: Cable and DSL Vital Statistics

Table 2: DSL and Cable Pros and Cons