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Friday, November 17, 2017

Floor It! The New 56K Modems

From the Tech Vault Dept.: Strictly for those who enjoy the intersection of technology and nostalgia, here’s my comprehensive look at the then-blazing 56K modem technology. It ran on CNet’s site in 1997, complete with appropriate graphics – none of which I retained. So it’s all the drier in the form below.

                                                                            
                   

THEY KEPT TELLING US it couldn’t get faster. Each time, something faster happened. For several years, modem speeds regularly doubled. When we reached 28.8 kilobits per second, however, we were told that was it. Nevertheless, a year ago the rate crept up to 33.6K (but just try to find many ISPs at that speed). And once again we were told that was it: analog phone lines had hit their limit. The only thing faster is digital, but ISDN lines are expensive and hard to get.

Now, suddenly, we have 56.6K modems. For ease of marketing, they’re referred to as 56K modems, although U.S. Robotics, a company with massive modem market share, terms its brand X2, while Rockwell, the firm that makes the modem chipsets for the majority of other modem companies, calls theirs K56flex. Thanks to these modems, Web pages are now flying onto screens at breathtaking speed – over plain old phone lines. But the two implementations of 56K technology, while based on similar principles, are incompatible. And it’s likely that the standard eventually ratified by the International Telecommunications Union (ITU) won’t be exactly one or the other. In its long history of ratifying transmission standards, the ITU has never simply adopted a single company’s proposal, so it’s not expected to happen this time – this time being around mid-1998.

Even when you get one brand or the other of these fast new modems on your desktop, thanks to the varying nature of telephone lines and ISP equipment, you’re not guaranteed to connect at such a high speed. And did we mention it works only in one direction? Stuff comes at you at speeds approaching 56K (thanks to an old FCC power limit, there’s an actual limit of 53K), but you’re still down to 33.6K going the other way.

The situation is still very much in flux as you read this, but one thing is certain: the hype is bound to get worse (or better, if you like hype) in the coming weeks as these two industry giants slug it out on the retail shelves. Given all the chest thumping and lack of official standards, what’s a user to do? To help you decide, CNET has gathered loads of information on both sides of the 56K technology battlefield. Take our tour of the technical side of where this all came from, then check out the various standards under consideration. See if you’re on the right upgrade path, and if you’re even a candidate for 56K. Finally, look at who’s making these modems and where you’ll find services to support them.

How it works

The secret to 56K success lies in phone lines, not modems. Old-fashioned telephone technology is analog: your words are converted to electrical impulses, fed over some wires, and converted back to words at the other end. Over the past 20 years, however, phone companies have been connecting to one another using digital hardware, although the lines to our houses are still analog.

Your phone changes what you say into a waveform that is carried to the local telephone company office. At the office, it’s converted to a digital signal by taking samples of the sounds 8,000 times per second (compact discs, by contrast, are sampled at 44,100 times per second). As the word “samples” suggests, the conversion isn’t constant. It’s more like a movie, in which a rapid series of still images gives the illusion of movement. With digital sound, a rapid series of pulses gives the aural illusion that it’s uninterrupted.

Each little sound slice is converted into an eight-bit number. Eight bits sent over the phone line 8,000 times per second gives you a transfer rate of 64,000 bits per second, or 64K. But every time that signal goes from analog to digital, noise is introduced. It’s called quantization noise, and it typically happens at both ends of the phone line as signals from you (or your modem) and the person (or modem) at the other end of the line are converted from analog to digital. In the past, enough noise was introduced to keep analog modem speeds down to a top speed of 33.6K (35K was judged the limit, but that’s not an easy number for a modem, which needs things to be divisible by various factors of eight).

Digital-to-analog conversions don’t have that noise problem. And here’s the key to the new modems: we’re all calling the Internet. That is, we’re clients to Internet servers, most of which are running digital modems. So there are no analog-to-digital conversions at that end, and one relatively noise-free digital-to-analog conversion at your end.

56K modems take advantage of that scenario by offering the speed one way only: from the server to you. It’s only 33.6K back from you to the server, but so what? Those are mouse clicks you’re sending; it’s information you’re getting back. What’s required is that your server be using a digital circuit, probably based on a special T1 or ISDN line, and that you and the server are using the same type of 56K technology.

Dueling standards

Essentially, there are two opponents in the 56K arena. U.S. Robotics is selling a line of modems with x2 technology, while Rockwell and Lucent Technologies are making chips to support K56flex. Modem manufacturers have been lining up behind one technology or the other. The two technologies are, of course, incompatible. Buy an x2 modem and you’ll only be able to connect at high speed with an Internet service provider (ISP) who supports x2. Likewise with K56flex. Both are backward-compatible to the V.34 standard for 28.8K and 33.6K, but that’s not what you’re making this investment for.

Who ultimately decides which 56K standard will prevail? The International Telecommunications Union (ITU) assigns those V. numbers, and will give the final word on how 56K will be put in place. But don’t expect to see anything from them until at least the middle of 1998. Meanwhile, Rockwell had a meeting in early March, 1997, at its California headquarters to discuss an interim standard for 56K modems, and began drafting a paper to submit to the Telecommunications Industry Association (TIA), which can approve a North American standard. This also would be the proposal that goes to the ITU, possibly by August, 1997.

U.S. Robotics was the first to submit a proposal for a 56K standard to the ITU’s Telecommunications sector (TR-30.1 subcommittee), and the company says it wants to deal directly with the ITU. Nevertheless, U.S. Robotics indicated a willingness to go along with an interim TIA-ratified standard to cover its domestic customers. There’s a certain risk, however: an interim standard is good for no more than three years, and still could be different from what the ITU eventually comes up with.

As to the final, standardized technology, Rockwell Semiconductor Systems president Dwight Decker says that it “will be a technology implementation that will not be straight K56 or the same technology as everybody else.” The process of affirming a standard “is that there are generally compromises and technology choices that are made over a period of time, and there will be pieces of many people’s technology.”

The bottom (speed) line


Although most of the modem world’s attention has shifted to the Web, there’s still a hearty system of bulletin board systems (BBSs) out there. But all versions of the 56K technology are based on the assumption that there’s a digital modem at the other end – which means a digital line (like a costly T1), something that few hobbyist BBSs can afford to install. If you’re a BBS habitue, don’t expect to see 56K access any time soon. (On the other hand, BBSs haven’t suffered the same speed problems imposed by the heavy graphics content of the Web.)

This also means that you’re not going to get 56K when you and a friend buy similar modems and try to connect. You still need that fully digital connection at one end for 56K to work.

The notorious FCC speed limit

Shortly after U.S. Robotics began releasing its x2 modems came the chilling news: the FCC won’t let modems transfer info faster than 53K. Turns out it’s a long-standing FCC regulation known as Part 68, and it was never intended to affect modems. Send too much power through the phone line and your conversation can get loud enough to creep into neighboring lines – like overhearing what’s said in the next apartment. This is called crosstalk, and Part 68 was meant to prevent it.

New phone line technology means that crosstalk may no longer be a problem, which is good for the 56K modem industry. An eight-bit digital phone signal has 256 different voltage states, but some of the voltage changes are so close together that they can be obscured by even a little line noise. Therefore, a little more power would improve those fast connections.

The FCC is looking over the ruling, says Elliot Maxwell, deputy chief of the FCC Office of Plans and Policy. “We’re not going to say to modem makers that this rule has to stand between them and paradise.”

What’s the competition?

So, who’s the fastest modem on the block? 56K technology is a one-way street with a few surprises – for example, it could get as high as 61K under perfect conditions, but such perfection is elusive. You need an especially clean line from your house to the phone company’s central office, all-digital service between there and your ISP, and no FCC power limit.

But you can get 128K with an ISDN line. In fact, Farallon Communications offers ISDN modems that promise to almost double that speed – to 230K – by maintaining the data compression already used by ISPs and phone company networks.

Integrated Services Digital Network technology was proposed nearly a decade ago, but it’s still hardly widespread. You find it most easily in high-tech places like Silicon Valley, and it’s working its way along the east coast thanks to Bell Atlantic.

You’re going to pay an average of $100 a month for that line, without even factoring in a digital modem and your ISP and phone call fees. The speed is great, but the upkeep is costly. Check with your local phone company first to price out your options.

Cable modems promise exquisitely fast transfer speeds – how does 28 megabytes per second sound? As with 56K modems, it’s a one-way speed, although the other direction isn’t exactly slogging through snow. It can get up to 3Mps and typically hovers at about 200K. But it’s a brand new industry that lacks the hardware to support a lot of customer demand, not to mention a lack of hardware standardization. If you’d like to be a Net pioneer, find out if it’s being test-marketed in your area.

Then there’s ADSL (Asymmetric Digital Subscriber Line) technology. Ten years in development, it’s fallen in and out of favor with phone companies and other designers – but the Internet boom has refocused that interest. It was designed to deliver video on demand, but never worked as well as satellite dishes and cable. Therefore, no parts have been produced in enough volume to bring down costs. A pair of ADSL modems went for around $3,000 two years ago; now they’re under $1,000 per pair and the price is still dropping.

It requires a dedicated copper line and a subscriber no more than two miles from a central office. Current phone line design uses 4 out of the 500 kilohertz of available bandwidth, but ADSL uses everything, and promises data downloads between 1.5 megabits and 6 megabits per second, with uploads at 640K. And you can transmit voice and data simultaneously over a single line.

It’s easier to implement than ISDN, but nobody has reckoned what the cost to a consumer might be. Still, several companies are working on trial implementations right now, including Nynex, Northern Telelcom, GTE, and Pacific Bell, so expect to hear more about this in the coming months.

Can I actually reach 56K?

You can’t tell simply by picking up the phone if your line can handle fast data transfers, but your modem may be able to tell you. Before you even invest in a 56K modem, check your connection speeds. Your Windows 95 dialer, for example, displays the speed during your online session.

Are you getting your modem’s worth right now? If your 28.8K modem – or, worse, your 33.6K modem – is routinely down at 21.6K or 19.2K, you’ve got noisy phone lines. To get much faster may be out of your reach, at least in your present neighborhood. A 56K modem won’t even attempt a faster connection if it can’t work at 33.6K.

If your connection is clean enough, check with your ISP to make sure you’re getting a compatible modem. If you’re already committed to one of the 56K standards, shop around for an ISP that supports it. Although there were early rumors of a price increase to support 56K, so far it looks like the rates will be holding steady. Smart ISPs have been preparing for this; the undercapitalized have to stay competitive.

If the line’s just too noisy, the modems automatically drop down in speed. If a modem thinks there are too many analog-to-digital conversions between you and the Internet, you’ll get a connection at 33.6K. Both the Rockwell and U.S. Robotics versions of 56K technology are backward-compatible, so if you call an x2 server with a K56flex modem, or vice-versa, it will be treated as a V.34 call – again giving you a 33.6K connection.

Behind the fancy promises is the fact that 56K is really a souped-up 28.8K technology. Each burst of information that comes to your modem includes a constellation of different electrical voltages, called signal encoding, that the modem translates into data bits. 56K technology throws extra voltage points onto the constellation map. No data compression is involved. An older data transmission technique, which the ITU numbered V.42, defined a means of compressing data (as you get with a Zip or StuffIt file) for online transmission, and it’s still in windespread use. If you hook up to a server that uses the V.42 technique, data still will be compressed and the throughput will be even significantly.

Can I upgrade my existing modem?

All sorts of promises were written on the box your modem came in. Whatever happened, there would always be an upgrade for it. Does this apply to 56K technology? The answer is a resounding maybe.

If you bought a U.S. Robotics Sportster 33.6 modem after August 15, 1996, you can upgrade it to 56K for $60. Likewise for any U.S. Robotics Courier V.Everything modem. And for those and the newer U.S. Robotics products, you’re promised an easy upgrade once the ITU standard is in place. The company is a big believer in flash memory upgrades, in which the pertinent software information is stored on an EEPROM (electrically erasable programmable ROM) and you simply download the new info from the manufacturer’s Website then run a software program that locates your modem and writes the new information to that chip.

Rockwell chipset-based modems come in both firmware and flash memory versions. Firmware means that the pertinent information is stored on a ROM chip, which needs to be replaced (and therefore has sockets for easy replacement). It’s a less expensive upgrade path than flash memory, and Rockwell predicts that it can save you $50 on the price of a modem.

The first rollout of Rockwell chips has been as firmware, but they’re looking forward to software-based upgrades, too. Whatever the case, Rockwell also promises an easy upgrade path once the ITU standard is finalized.

Some current Rockwell chip-based modems can be upgraded to 56K with a chip swap, but you’ll have to consult the manufacturer for availability and instructions. Hayes, for example, is offering a free trade-in program for any of their modems bought after Feb. 1, 1997, as well as a $99 competitive trade-in for other manufacturers’ modems. In most cases, a hardware upgrade on an internal modem is an easy matter of replacing one socketed chip with another. With an external modem, you’ll have to open the box to do so. It’s up to the individual manufacturer to decide how to handle the issue, so check it out before you buy. Websites are good info sources.

Where can I get it?

All of the companies involved are quick to bring out the supporting cast. U.S. Robotics has lined up modem makers Logicode and Cardinal, computer makers Hitachi, Dell, and Acer, and online services such as America Online, Compuserve, MCI, Netcom, and Prodigy. Check out their online list of ISPs [it’s long gone] to find a local connection.

Rockwell, meanwhile, offers a list of modem manufacturers [also long gone] that includes Archtek, Best Data, Boca Research, Creative Labs, Diamond, Hayes, Microcom, ZoomTelephonics, and many others. Also check out their lengthy ISP list [also long gone].

Once the ITU standard is in place, look for all of the ISPs to move in a direction that supports the standard. It costs them a lot more than the price of a single modem, though, so both Rockwell and U.S. Robotics are promising that the upgrade path to the standard will be painless even at the server end.

In the meantime, which should you choose? U.S. Robotics products have a strong customer base, but the Rockwell chips are in almost every other modem brand you’ve ever heard of, and both brands have been hitting the retail shelves since March. If it’s a matter of your ISP, you’ll find that the big providers such as America Online, CompuServe, and Prodigy are looking at supporting both until the ITU standard is approved. If you have a favorite local ISP, find out what the company’s plans are before you make an investment.

CNet, April 1997

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