Wide-Area Wireless Networks

Nowhere is the acronym stew more confusing than it is with wireless networks that cover wide areas. There are several basic types of technologies used for this sort of connectivity, each of which has its own series of acronyms. Worse, each of those technologies is evolving, with future generations having different names (and acronyms) than the current generation.

		Wireless Technology Guide
		• Short-Range Wireless     - Bluetooth     - UWB     - NFC And ZigBee • Medium-Range Wireless     - Wi-Fi     - Wireless Mesh • Wide-Area Wireless Networks     - 3G Service     - 4G And Wireless Broadband

The similarity among all these different types of networks is that they connect you to the Internet without wires over wide swatches of territory. One more thing to understand is that these networks typically operate over licensed spectrum. That is, they use portions of the wireless spectrum that are regulated by the government. By contrast, technologies like Wi-Fi and Bluetooth operate over the unlicensed spectrum and are more prone to interference and security problems.

3G Service
Cellular operators have been touting third-generation, or 3G, cellular data service since well before the turn of the century, and in the last year, it has finally arrived. This service provides decent data throughput speeds -- currently about 500 Kbps, give or take -- over the networks run by cellular operators.

While not as fast as most wired broadband connections, 3G offers one tremendous benefit: Like cellular voice service, it is readily available throughout a cellular operator's service area. All you need is a card for your laptop or a mobile device that supports the service.

But here the acronym soup starts to boil furiously. Some of the confusion is created by the fact that, in North America, there are two separate core technologies used by cellular operators. Some operators, such as Verizon Wireless and Sprint, use CDMA (Code Division Multiple Access) technology. Others, such as Cingular, use GSM (Global System for Mobile Communications) technology.

Cellular operators that employ CDMA technology currently are using 1xEV-DO (Evolution-Data Only) 3G service, which is sometimes called CDMA2000. That will migrate to EV-DO Revision A starting in a year or two, which will provide speeds of roughly 1 Mbps. GSM operators use UMTS (Universal Mobile Telecommunications System), which is sometimes confusingly called WCDMA (Wideband CDMA). That technology already is evolving into HSDPA (High-Speed Downlink Packet Access), which eventually will evolve into HSUPA (High-Speed Uplink Packet Access).

Adding even more confusion is the fact that these technologies have both theoretical speeds and real-world speeds. For instance, HSDPA has a theoretical maximum throughput speed of more than 3 Mbps. Current real-world speeds, however, are in the 500 Kbps to 700 Kbps range. When considering 3G, make sure you are clear whether the speeds the vendors are promising are theoretical or actual speeds you can expect.

Another caveat is price -- this stuff is expensive. The going rate for 3G service in the U.S. is $60 a month on top of a voice plan and a two-year contract, more if you don't have a voice plan with a specific carrier. You'll also need a 3G card for your computer or a mobile device, such as a smartphone, that supports your cellular operator's flavor of 3G. You get those from the cellular operator, and prices vary widely depending on your service plan and contract length.

Yet another gotcha relates to the fact that some carriers call their 3G service "unlimited." However, if you read the fine print, you'll find that it's anything but unlimited. Most carriers limit how much you can download and what the service can be used for. For instance, some carriers prohibit use of this service for downloading or streaming audio or video. If you go beyond the limits, the carriers reserve the right to cut your service.