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This chapter is from the book

This chapter is from the book

Current State of Cable Modem Access Versus DSL

So what's holding up DSL and cable modem access? If you have been told that the lack of widely accepted standards is the main factor delaying cable modem and xDSL access, think again. Lack of standards is, at most, a minor factor in the delay of widespread access.

Because solid standards have not been established, xDSL and cable modem access are being held up. So, let's put things in perspective, even though it is certainly true that the lack of standards is having some effect.

Cable modem and xDSL services are dedicated subscriber services. You use your cable modem or xDSL box to connect to one place—your service provider. You do not carry it around with you like a modem. Where you expect to move the device from place to place or to a different service provider (as with a 56K or 33.6 modem), standards affect only the end user in cases. Your cable modem or xDSL box is like your television cable box (which you never move—you buy it or lease it with the service, and it stays with the service), not like your modem. By allowing vendor competition, it is true that standards will lower hardware costs a bit. This, in turn, will lower your equipment costs, but not much. The important thing is that if your provider can offer you service at a price you like, that is what matters most to you. The fact that he or she will be able to buy the box that he or she leases to you for $10 a month for $100 less next year is simply not that much of an issue. Anyway, it's probably a small fraction of the overall cost of providing the service.

The history of cable modem access by Cablevision 4 on western Long Island over the last several years tends to support this. The original beta access used a specific brand of cable modem (which was provided with the service). When the beta program ended, the original equipment was discarded in favor of a newer, higher-performance product made by LanCity 5. This didn't affect end users much—they just returned the original modems and installed the new ones. The current service provides a 10Mbps Ethernet connection for under $70 per month (this includes the lease of the cable modem unit, connection, and ISP service) for residential customers. This service is about three to five times faster than a full T1. The LanCity cable modem follows the only real standard that matters so far—it connects to the user's PC using standard 10Mbps Ethernet like most other xDSL units and cable modems.

You'll have to look elsewhere than the lack of widely accepted standards if you want to know why xDSL and cable modem service is slow in accessing. Maybe you should wonder whether the cable enterprises are simply afraid of moving into a new technology that they don't understand, whether the telcos aren't that eager to access a DSL service in direct competition to their data T1 and T3 services (and with a lower price tag), and whether anybody has enough backbone capacity to support the large numbers of high-speed customers that the new service would attract. Incidentally, Cablevision claims no immediate plans to offer enterprise services. It is not interested in going outside its traditional market to offer service to more demanding enterprise customers (who generally use a higher percentage of the available bandwidth for a larger part of each day than residential customers).

Nevertheless, the battle for broadband data services to the home and enterprise has been played out as a battle between the telephone enterprise (telcos) and the cable operators. The battle has been fueled by "arms merchants," the silicon suppliers and xDSL and cable modem box vendors, selling both hype and product to both sides. With over 470,000 in commercial operation in North America alone and the entire industry rallying around CableLabs 6 promulgated standards and retail distribution models, cable modems have taken the early lead. A tremendous lure for the cable operators is the potential for remote LAN access and IP telephony on top of Internet access. Meanwhile, in an attempt to solidify the industry and to catch up with cable deployments, the DSL community is moving toward a low-cost, splitterless G.lite standard. G.lite could be an easily deployed, low-cost technology that carries a dedicated IP pipeline on top of the twisted-pair voice connection leading into virtually every home. G.lite could also be just another vegetable in DSL alphabet soup. The major regional Bell operating companies (RBOCs) have recently announced DSL access plans for 2000–2001, despite a myriad of technical and enterprise hurdles.

So what's real, and will there be a winner in this battle for broadband in the local loop? Well, a recent bitter struggle among equipment manufacturers is threatening new industry rules that could make broadband in the local loop or high-speed Internet connections less expensive, easier to use, and available to far more people.

DSL Progress Is Thwarted

The infighting centers on the so-called G.lite standard, which is designed to simplify cable modems used for digital subscriber line (DSL) connections. Thus, manufacturers need to make products that can work together seamlessly to speed wide-scale adoption of DSL because the market is littered with different technologies.


Digital subscriber lines carry data at high speeds over standard copper telephone wires. With DSL, data can be delivered at a rate of 1.5Mbps (around 30 times faster than through a 56Kbps modem). Also, DSL users can receive voice and data simultaneously, so small offices can leave computers plugged into the Net without interrupting phone connections. Currently, DSL is expensive because specialized equipment—a splitter—needs to be installed at the subscriber's location. DSL Lite, the consumer-ready version of DSL, requires no such splitter and promises comparable access speeds at a cheaper rate.

This type of conflict is common with emerging technologies, but rarely are the stakes as high as they are today. High-speed access is largely associated with the growth of the Internet itself, and billions of potential dollars hang in the balance for those enterprises that come up with the winning solutions to break the widespread bottlenecks across the Web.

Moreover, the rhetoric is particularly rancorous in the G.lite debate. Critics say that G.lite modems do not work well with current technology, according to service providers, and some manufacturers are now fighting to see their own products adopted as the industry standard.

In some cases, these technologies can't even communicate. It's not just that you need a G.lite modem. You need a G.lite modem from a specific manufacturer. And that's the same as no standard at all.

While equipment makers argue over how to best implement the G.lite standard, competition from high-speed cable modems is intensifying. The cable industry has already established a standard set of rules for cable modems, giving the group a leg up on its DSL rivals.

According to TeleChoice 7, about 380,000 DSL lines were in use by the end of the last quarter of 1999, with 86% of these in residences. Cable modems have reached well over three million users.

Just as telephone enterprises and Internet service providers such as America Online 8 and Prodigy 9 ramp up their marketing machines to push high-speed Net services across the country, the lack of a universally accepted standard could slow the spread of DSL. To have an absolute standard that leaves no variation in the way that equipment vendors can make their equipment is not practical.

All in One

So that different enterprises create products that can work with each other, many industries push for technology standards, or rules. For instance, VHS is a standard for videotape. Regardless of the enterprise that manufactured the VCR, a VHS tape cassette will play on any VCR machine that is built to handle that certain type of tape.

Standards are critical in the communications world. If a consumer buys a modem, it must work with his or her computer as well as the ISP.

You can't get to the point of popularity reached by ordinary analog modems without a standard. For example, people should be able to buy a computer at CompUSA 10 or a similar store, take it home and plug it in, and have it work with their ISP.

Several years ago, the Internet and computer industries coalesced around the G.lite standard for consumer DSL. It was ratified by the International Telecommunications Union 11 as the worldwide set of official technical guidelines.


The ITU, a Geneva, Switzerland–based international organization that governs the communications industry, recently approved the G.lite standard, a lower-speed DSL technology aimed at the mass-market consumer.

Rather than wait for a phone enterprise technician to install a modem, the standard is aimed at making DSL relatively cheap because it would allow a consumer to buy a modem and plug it into a PC. The challenge is to make sure that modems and other equipment made under the G.lite standard all work together.

Lab Tests

The University of New Hampshire 12 has set up a lab where enterprises such as Intel 13, Alcatel 14, Lucent 15, and others can test their modems against each other and against other products—all under the auspices of the ADSL Forum. Nevertheless, some enterprises already say that they comply with the standard, and some computer makers (led by Compaq 16 and Dell 17) have already begun shipping machines with standardized DSL modems that conform to G.lite rules. However, the modems still won't work with all ISPs and telephone enterprise equipment.

The big telephone enterprises (the enterprises that will invest the most money in DSL equipment), for their part, are testing G.lite technology and hope that manufacturers will end their differences as soon as possible. Most phone carriers are using different versions of DSL on an interim basis in the meantime.

This has taken the interoperability process to a whole new level. It will take time to sort it out.

So, how prevalent are cable modems and DSL in major U.S. markets? Let's take a look.

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