Another Standards Debacle: EDGE
By Michael Grebb, Tue Apr 17 00:00:00 GMT 2001

EDGE is ready to turn up the data rate well ahead of UMTS - and has many people asking how the two technologies relate: Compliments, or competitors?


The hype surrounding the next generation of wireless networks has been percolating for at least a few years without much in the way of specifics. When will consumers and businesses actually be able to use 3G networks? And what how much bandwidth do they need?

3G services based on the Universal Mobile Telecommunications System (UMTS) can achieve up to two megabits per second. But is that really necessary? "The question is what will people want," says Bill Bandt, a partner in Andersen's technology, media and communications practice. "Will I be unfulfilled if I can't have a videoconference on my pocket phone?"

Because of such questions, many are talking about transitional technologies that might pave the way for those fancy networks by re-engineering existing CDMA and GSM infrastructures. On the GSM side, many argue that a technology called EDGE (enhanced data rates for global evolution) will be a big player worldwide because it can pump data at up to 384 kilobits per second through existing infrastructures.

Of course, EDGE is key to fill in pockets in which a carrier doesn't have additional spectrum to augment its existing GSM network. "EDGE today is seen is a viable technology for those carriers that were unable to obtain a UMTS spectrum license," says Ed Valdez, director of marketing for Motorola's Wireless Communications unit. "Should GPRS services prove to find a wireless killer app and the 3G rollout takes longer to deploy, EDGE can provide a good interim solution."

Still, others argue that carriers would be better off skipping EDGE in favor of CDMA-based broadband technologies. "GSM is a voice workhorse that will be phased out over time," predicts Cliff Raskind, director of global wireless practice at Strategy Analytics, a research firm. "EDGE has been a non-starter in Europe. And in the U.S., I don't think EDGE is going to play a big role." The debate continues...

How it works


At issue is modulation. CDMA (code-division multiple access) is by definition a "code-division" technology that makes more efficient use of the spectrum by constantly sending packets of encoded bits to various devices simultaneously. This allows for reuse of spectrum that would otherwise be tied up with wireless traffic (a key benefit for bursty data applications).

GSM-based networks, however, generally use TDMA (time-division multiple access) originally designed for less bursty voice traffic. In addition, experts say TDMA power requirements can be greater as well. That can increase the size of TDMA devices compared to CDMA-sized gadgets with similar features.

Of course, the CDMA has its own problems. While many experts agree that CDMA will be the technology of choice for 3G networks of the future, it's unclear when the infrastructure will be ready.

In Europe, much of the 3G spectrum has only recently been allocated (and for astronomical prices). In addition, most of the world (except for the U.S.) uses devices that only work on GSM networks, meaning that switching much of Europe and Asia to such new technologies as CDMA 2000 and wideband CDMA (WCDMA) would require users to buy new handsets (Handsets, by the way, that will likely be more expensive than GSM devices because there are fewer CDMA networks around the world and therefore lower economies of scale).

Still, experts say the choices for carriers and vendors aren't easy. "What are you going to do," ponders Brandt, "lay down or roll out a new technology that forces people to buy new handsets? We're not talking a software upgrade. We're talking, 'throw out your old phone.'"

Fundamental uncertainties


In the meantime, the overbearing question of whether consumers and businesses need broadband wireless connections looms large. After all, videoconferencing has been possible over broadband landline networks for years and still remains a relatively niche market. WCDMA, for example, uses UMTS.

But experts say the short-term need for such speeds is questionable, short of some specific business situations. One example: A sales rep could download a product presentation on the spot for a prospective buyer right to the laptop - in seconds. “That’s the difference between signing the guy right there and having to say, ‘I’ll get back to you in two days and having the interest chill,’” says Warren Wilson, senior analyst at Summit Strategies.

But such high-bandwidth applications over 3G networks could be a long way off. In the meantime, EDGE technology aims to fill the gap—at least in the short term. EDGE uses a GSM technology called GPRS (general packet radio service) to hypercharge the exchange of data packets over the network. The result can be much higher transfer rates than now realized over GSM networks.

But while laboratory tests can achieve speeds of up to 384 Kbps, Wilson points out that speeds can diminish in the field. “Those are peak network speeds,” he says. “There’s very often a substantial difference with what you really get.” But EDGE may perform closer to its promise than even WCDMA. According to Summit Strategies, EDGE can slow from 384 kbps to 80 kbps in the field while UMTS can plummet from its touted 2-Mbps to only 250 kbps—a far more dramatic slowdown.

Of course, CDMA vendors have even argued that EDGE speeds can degrade to around 10 kbps—similar to today’s narrowband wireless services. “EDGE and GPRS are 2.5G technologies,” says Mark Steele, senior vice president of business development at CDMA vendor AirPrime. “Everybody is going to do CDMA. The question is when.”

More important, perhaps, is to when the market will demand it. After all, many users just want to improved latency and the ability to send and receive packets quickly but not necessarily lightning fast. And one of the big advantages of EDGE is that its modulation makes far more efficient use of GSM networks, which can help manage bigger traffic loads.

“At this point, it is premature to speculate on how consumers and businesses can take advantage of this - it is a complex equation as cost, service, content, battery life, and size must be considered,” says Valdez. “In many ways, one can liken this to the early days of the Internet - many providers trying to find the formula that users would accept.” But how important are those blazing speeds?

“People driving the need for speed are high-end people, and I’m not sure if there’s a mass market for that,” says Brett Warthen, senior vice president of wireless technology and strategy for Captaris, which sells wireless business applications. “Higher speeds are more an issue for people with laptops. The compelling thing about EDGE is it can be deployed quicker and more cost effectively right now.”

Indeed, that’s a major advantage of EDGE. With 3G networks seemingly a long way to reality, EDGE presents one of the best ways to transition into faster services - especially in parts of the world primarily built upon GSM networks.

“Think of EDGE as adding a few more rooms to your house,” says Gary Cherie, a spokesman at Nokia. “As your family grows, you need more space. Then one day when everyone has really bought off on this concept of mobile Internet and traffic is extremely high and constant, you go to WCDMA.”

Of course, customers won’t likely follow unless EDGE and other transition technologies provide a good experience. “If the performance on EDGE networks doesn’t hold up, that may actually hurt overall perceptions of 3G,” says Steele. The challenge for EDGE proponents is making sure that doesn’t happen.

Michael Grebb has previously written for The Industry Standard, Business 2.0, and eCompany. From Washington DC, he covers the impact of mobile technology on modern society.