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What's Going On Here?

How much do you know about Digital Subscriber Line (DSL)? This quiz tests your basic knowledge about DSL.

More About DSL

The race is on to provide high-speed but low-cost Internet access to small businesses and homes. Digital Subscriber Line is one of the options from which you can choose, with your other major options being Internet access over Cable (as in Cable TV), and newly emerging fixed broadband wireless options (see our wireless page).

DSL provides connectivity at speeds that are up to 100 times faster than analog modem (56k) over the same pair of wires that you use today for your telephone. In fact, with DSL you can be on the phone talking at the same time you're surfing the Internet, all with just one phone line! Some people have found that there is a slight noise problem when doing this so you might want to invest about $14 a phoneset for a DSL noise filter.

DSL has had incredible market acceptance spurred on by very aggressive pricing from companies like Pacific Bell (SBC) here in Northern California. Unfortunately, the pricing has been so low to attract customers (and keep them from trying cable), that many DSL service providers have been losing money on each account. No matter what anyone says, you can't lose money on each subscriber and try to make it up in volume! Today many DSL providers have gone under, perhaps the most famous of which was NorthPoint (sady, a WKMN client).

You can typically expect to pay $49 a month for "basic" DSL service. You pay that plus the regular cost of telephone service on that line (about $20 more a month plus usage). Most basic home DSL lines include the ability to connect regular analog phones to RJ-11 jacks, just like normal phone service. In some cases you'll get something called a POTS (Plain Old Telephone Service) splitter, which is basically a box that you use to connect your analog phone wires.

More expensive DSL service, sometimes called "enhanced" may provide higher data rates but more often than not is enhanced by the addition of features like static IP addresses (more than one). More on that can be found below. If you'd like to use a comparison shopping site to find DSL service that's just right for you, here are a couple of options:

• Broadband.com
• BroadbandBuyer.com

Types of DSL

There are a wide variety of types of DSL available, depending on your budget and your distance to the nearest telephone company Central Office. Most low-cost forms of DSL are asymmetric, meaning that upload speeds and download speeds differ. Here at WKMN we have ADSL from Pacific Bell with download speeds guaranteed to be at least 384 kbps but which typically come closer to the speed of T1 (1.544 Mbps). Our upload speed, however, is 128 kbps. Since that is not an adequate speed to support our hosting a web site, we host our site at a hosting provider.

Addressing Issues

DSL accounts come with either a dynamically assigned TCP/IP address or static address(es). Most low-cost accounts designed for home offices or very small businesses offer a single dynamically assigned address. The benefit to the provider is that they can use a smaller pool of addresses to support a larger number of users. Although these providers will claim that their DSL service is "always on" the truth is that your connection, when idle, times out. Each time you want to use the Internet after an idle timeout period, you have to reconnect and obtain an IP address. Granted, this may take a couple of seconds, but you are not really always on! A common protocol used to provide your DSL connection and IP address in this scenario is the Point to Point Protocol over Ethernet (PPPoE). Your provider will give you PPPoE software for your PC or Macintosh. You can use that software or other software available on the Internet. With a dynamically assigned address, it is more difficult to share a DSL account with multiple users on the same LAN, although not impossible. It is also more difficult to host an email server, web site or FTP site on your DSL connection, although again, not impossible. Slightly more expensive accounts come with at least one fixed IP address. With fixed addresses, it is easier to share the DSL connection and host email and web servers.

PPPoE Giving You Trouble? Speaking of PPPoE, many DSL customers are having terrible trouble with the PPPoE software clients provided by their ISPs. We think that is one of the key reasons people visit this page! If you are one of those people, consider either trying a different PPPoE software client listed below, or try one of the routers listed below in the hardware section. Before buying a router, make sure it supports PPPoE (most on the list below do).

Comprehensive Introduction to DSL

If you want a quick but comprehensive introduction to DSL, check out the whatis.com overview. We recommend some more DSL related links and books in the next section (below).

Sharing a DSL Connection

One of the most common questions about both DSL and Cable Modem Internet access is "How can I share my DSL or Cable Modem connection with multiple computers on my home network?" Of course you can! Listen to our "On the Air" commentary about sharing your DSL connections and you can get step-by-step instructions (requires Real Audio G2)! You'll learn about sharing a DSL connection using a PC with two Ethernet cards and Internet sharing software. If you don't have Real Audio G2, you can access this On the Air commentary using Shockwave.

After you've listened, we have an exercise to show you how to wire things up below. Further below, we have links to software you can use to share your DSL connection as well as tutorials, FAQs, and hardware solutions for sharing DSL and cable modem connections.

The hottest news in sharing DSL, by the way, is that a number of vendors are starting to ship DSL routers with built-in wireless LAN access points. Cayman and Linksys are just two examples of companies smart enough to see the trend.

Community Networks via DSL are starting to pop up all over the country. One person gets a DSL connection, pops a pringles can antenna out his or her window, and the neighbors point their pringles cans at the DSL house and presto changeo.... you've got a community network. Visit our community networks page by clicking here.

Is Your Connection Secure? People are often surprised to discover that their DSL (or cable modem) connection is not secure. If file sharing is turned on, for example, it's possible for someone out on the Internet to easily hack into your computer and view or modify your files. DSL and cable modem connections, despite advertising claims to the contrary, are often architected as "shared" connections. The nature of your connection exposes you to significant danger if you don't have protection. If you are connecting your network to the Internet via DSL or Cable Modem, make sure you have a device or software that provides protection. If you have a single computer, you either want to turn off file-sharing, or better yet, install a personal firewall. McAfee, among other companies, offers personal firewall products.

Share that DSL Connection Exercise:

Now that you've listened to our On the Air about sharing a DSL connection, you should be a regular DSL sharing genius! Are you? Let's see. In the diagram below, we have a DSL connection, a DSL modem, a PC with two Ethernet cards and some kind of Internet Sharing software, an Ethernet hub and two PCs just waiting to use that PC as their gateway to the Internet. Follow the instructions and hook everything up! The only thing missing is the software you would need on the PC that has the two Ethernet cards. We have links to quite a few options below.

Hardware Alternatives:

Rather than configuring a PC to share Internet connections as shown above, you might want to investigate dedicated hardware alternatives, sometimes called routers. We have a whole list of router products in the tables found below. One of the key features you need to look for is support for PPPoE (Point to Point Protocol over Ethernet). Many DSL providers are moving away from static assigned IP addresses and "always-on" connections towards PPPoE, which uses dynamically assigned IP addresses and requires a connection process. PPPoE sessions time out when there is inactivity and must be relaunched. For home users, emerging options for sharing DSL connections are wireless Local Area Networks and Home Phoneline Networks. Intel's AnyPoint and 2Wire's Residential Gateway are examples of products you might want to explore and we have links to them in the tables below. (2Wire's been getting a lot of great press with their recently released and anxiously awaited residential gateway products!)

Pardon us while we mention a product with which we have significant experience, the InterJet II. WKMN develops training for IBM on their Small Business WebConnections solutions. The InterJet II is an award-winning, all-in-one Internet product that includes a router, firewall, NAT, DHCP server, FTP server, web server, email server, and more. Check out our wiring closet where we did some of the hardware installation training for the InterJet II product!

Our Network: We have a 10/100 Linksys Ethernet switch connecting our wired Ethernet PCs to the InterJet II. The InterJet is connected to an Alcatel 1000 DSL modem which is then connected to our Pacific Bell DSL service. The ORiNOCO Residential Gateway is connected to our 10/100 switch. Since our InterJet performs both DHCP and NAT, we did not need these services from the Residential Gateway. For small offices and homes, the fact that the ORiNOCO Residential Gateway does DHCP and NAT and basic routing functions, makes it an incredibly good value. Unfortunately, today The RG1000 does not handle PPPoE for multiple stations.

Interested in wireless? We've just completed what we consider to be one of our best pages yet! Learn all about home and SOHO networking with wireless LANs on our wireless page.

Additional Resources and Books:

	DSL for Dummies by David Angell Buy this book now at 20% off and we donate WKMN's proceeds to the Second Harvest Food Bank and Ecumenical Hunger Program.
	Understanding DSL Technology by Thomas Starr, John Cioffi, and Peter Silverman Buy this book now and we donate WKMN's proceeds to the Second Harvest Food Bank and Ecumenical Hunger Program.
	The DSL Bible Pre-order this book now 1t 20% off (due for release in July 2000) and we donate WKMN's proceeds to the Second Harvest Food Bank and Ecumenical Hunger Program.