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Road map to 3G

This year, it looks like there will be a little high-speed wireless reality to go along with the hype. U.S. providers are finally beginning to roll out high-bandwidth wireless services, including e-mail with attachments, instant messaging and always-on data connections. And CIOs should be able to take advantage of these tools once they sift through the marketing jargon.

The wireless industry categorizes its technologies by stages of development. Analogue networks (the first generation, or 1G) started the revolution. Digital wireless became 2G. High-speed data combined with advanced voice capacity is the third generation (3G). Back in the late 1990s, when it became clear that 3G network speeds were still years away, an interim stage called 2.5G emerged. This half step to 3G will happen this year, and many CIOs think that it will be sufficient at least for the time being.

Nancy Bryant, CIO of 1st City Savings Federal Credit Union in Glendale, Calif., says that she is going to upgrade when the networks get faster. Bryant uses Sprint PCS Group’s 2G wireless modems for backup support and out-of-the-office business, but faster would be better, she admits.

“We will probably go even faster than 2.5G speeds; if I could do it all wirelessly, I would,” says Bryant.

Faster, Faster

Each wireless generational advance includes an increase in data speeds. Second-generation networks in general are slow, with data speeds similar to or less than a 14Kbps modem. Another 2G drawback is that the data connections are circuit switched – meaning users must initiate every connection. Both these issues, however, are partially solved by 2.5G networks. They use packet-switched networks, with an always-on data connection. And data also travels faster than on 2G networks, with speeds similar to a 56Kbps modem. The Holy Grail of wireless – 3G – ups the performance even further, purportedly achieving speeds as high as 384Kbps – fast enough to make multimedia features such as streaming video a possibility.

In the United States, the current stage is described as 2G moving toward 2.5G. (Europe and parts of Asia have an edge on the United States, with Europe well along 2.5G and Japan at or near 3G.) Most major wireless carriers say they are committed to building networks by the end of the year that can transfer data at average speeds between 40Kbps and 80Kbps. But just because the networks are capable of moving data at those rates does not mean users will always experience them (just as having “nationwide coverage” from your mobile voice carrier doesn’t mean you’ll always be able to make a connection).

And the faster speeds don’t necessarily change the basic uses for wireless devices. With 2.5G, users won’t be watching The Matrix on a PDA. But checking e-mail and even opening attachments which can be ridiculously time-consuming tasks on 2G networks, should become feasible. Downloading audio files and digital images may even be reasonable goals.

Two Ways to 3G

The simple generational names for wireless technology mask an ocean of complexity behind the scenes. For instance, when people talk about 3G they may be referring to either CDMA2000 or wideband CDMA (W-CDMA), both of which are competing technologies.

Both technologies describe different routes to full 3G capabilities. The CDMA2000 road to 3G includes a stop at 1x or 1xRTT (radio transmission technology), which promises average data speeds of 60Kbps to 80Kbps (at least according to Sprint PCS). Both Sprint PCS and Verizon Wireless Inc. say they plan to introduce their first 1x networks this year.

Here’s where some confusion comes in: The International Telecommunications Union (ITU) approved calling the first phase of 1x a 3G technology, and carriers are marketing it as such, but some analysts remain reluctant to call it true 3G. Average speeds for the first phase of 1x are closer to speeds characteristic of 2.5G networks. Phase two of 1x is the next step for CDMA2000 networks, which promises speeds up to 288Kbps performance more in keeping with the 3G promise.

Meanwhile, the next phase of the W-CDMA path – the direction taken by AT&T Wireless Services Inc., Cingular Wireless LLC and VoiceStream Wireless Corp. – is general packet radio service (GPRS), but getting people to agree on GPRS data rates is difficult. The range for average data speeds wavers between 20Kbps (according to analysts) and 60Kbps (if you talk to the service providers). After GPRS comes enhanced data rates for global evolution (EDGE), which promises data speeds as high as 384Kbps, but average speeds may be slower.

How much slower these technologies are in the real world remains to be seen. The speeds that wireless data users actually experience are often significantly lower than the theoretical maximums. Actual performance depends on a number of factors, including a user’s location and how many other people are on the network at the same time.

The achievable speeds for 1x and EDGE, for instance, are much lower than their theoretical speeds, says Shiv K. Bakhshi, a research manager for 3G wireless infrastructure at Framingham, Mass.-based IDC (a sister company to CIO (US)‘s publisher, CXO Media). While Bakhshi understands that 1x and EDGE have been called 3G by the ITU, it was on the grounds of theoretical speeds of 384Kbps and users shouldn’t expect that kind of performance in real settings.

Other Wireless Ways

Then there’s a technology that doesn’t fall neatly onto one route to 3G. Nextel’s proprietary voice and data network, iDen, offers data speeds around 15Kbps to 16Kbps, and with compression technologies available this spring the speed could increase to between 40Kbps and 100Kbps, according to Nextel.

While the technologies certainly vary, for practical purposes the differences are all about speed and coverage. It’s difficult to find concrete answers about speed, and coverage will vary according to each carrier’s network. The entire Sprint PCS network, for instance, will upgrade to 1x at the same time halfway through this year, and the whole VoiceStream network is already at GPRS. Other carriers are moving market by market and making advanced services available in some areas they cover but not in others, which could be an issue for CIOs looking to implement nationwide wireless data services. (AT&T and Cingular say they plan to have national coverage by the end of 2002, with Verizon claiming it will achieve almost complete coverage in the same time frame.)

The endgame, true 3G in the form of either W-CDMA or 1x evolution-data and voice (1xEV-DV) – the CDMA2000 technology – is still a few years away. In the meantime, CIOs who are already using 2G wireless data technologies say the faster the better. Analysts think the next step, 2.5G or similar services, will be fast enough to satisfy most data users, unless they are trying to stream video to their phone. But why would someone want to watch a video on such a small screen?

“No one will tell you that fast is too fast, but for most of the applications we are going to be using over the next year, the speeds we’re going to have will be fine,” says Ken Hyers, a senior wireless analyst at Newton, Mass.-based Cahners In-Stat Group. Unless you want to use wireless technologies to stream video, there’s no reason to wait for 3G, says Hyers, who doesn’t think we’ll see true 3G until 2005.

Faster is always happier, agrees Jim Cogliano, COO of The Sullivan and Cogliano Cos., a Waltham, Mass.-based IT staffing company that has 50 reps using Nextel’s mobile data services to sync up to their Outlook accounts via wireless phones. Cogliano says his current speed isn’t bad.

There’s still a lot of skepticism about these faster networks actually materializing. Santosh Patel, director of service operations for North America at Honeywell in Morristown, N.J., has 1,400 technicians using a wireless field service automation application on a combination Cingular 2G network and Wireless Matrix satellite network. “Data speeds around 56K will open up more possibilities, and 3G will open up even more,” says Patel, “but I’ll believe it when I see it.”

WIRELESS GLOSSARY

1XRTT: 1x radio transmission technology is the next step on the CDMA2000 path to faster wireless networks. This year Sprint PCS and Verizon Wireless plan to introduce the first phase of 1x networks that are capable of transferring data at average speeds between 60Kbps and 80Kbps, according to Sprint PCS.

1xEV-DV: 1x evolution-data and voice is the third step on the CDMA2000 path. When it becomes available (not until at least 2003) it will increase both voice and data capacity on the supported networks. Sprint PCS, which says it will introduce 1xEV-DV in 2004, claims the technology will transfer data at rates between 3Mbps and 5Mbps.

CDMA: code division multiple access technologies allocate bandwidth for users of digital wireless devices. CDMA uses codes to differentiate among multiple transmissions carried simultaneously on a single radio frequency band.

CDMA2000: encompasses all the stages of 1x technologies. It is considered a 3G technology that increases voice and data capacity and could theoretically provide data speeds up to 5Mbps. CDMA2000 3G technologies compete with W-CDMA technologies.

EDGE: enhanced data rates for global evolution is a step up from GPRS on the W-CDMA path to 3G technologies. EDGE is supposed to transfer data at speeds up to 384Kbps, but average performance may be slower.

GPRS: general packet radio service is a technology that sends packets of data across a wireless network at theoretical speeds up to 114Kbps. It is a step up from the older circuit-switched method as users do not have to dial in to networks to download information. GPRS is the next step for GSM networks on the W-CDMA path.

GSM: global system for mobile communications is a standard for coding and transferring data through the wireless spectrum. It is the predominant standard in Europe and Asia and is an alternative to CDMA. GSM digitizes and compresses data and sends it down a channel with two other streams of user data. The standard is based on time division multiple access.

TDMA: time division multiple access lets large numbers of users access one radio frequency. TDMA breaks down data transmission, such as a phone conversation, into fragments and transmits each fragment in a short burst, assigning each fragment a time slot.

W-CDMA: wideband CDMA is a 3G wireless technology that allows for high-speed, high-quality data transmission at speeds of around 2Mbps. Derived from CDMA, W-CDMA digitizes and transmits wireless data over a broad range of frequencies. It requires more bandwidth than CDMA but offers faster transmission because it optimizes the use of multiple wireless signals (unlike CDMA’s one signal). W-CDMA competes with CDMA2000.

Danielle Dunne is editor of CIO’s Wireless Communications Research Center.

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