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Top 10 Things To Know About Wireless Curious about interoperability, encryption, management and standards? Here's the lowdown on wireless technology today. By Joel Conover 10. Cost Thanks to integrated chipsets from Intersil Corp. (formerly Harris Semiconductor), Lucent Technologies and other component manufacturers, the cost of developing and delivering a wireless solution has dropped significantly. The result is a PC Card solution that is on par with that of wired Ethernet. The products we tested for this article list for $179 to $249 per card? A price that can be easily justified for home office or mobile users. Wireless has become cost effective; for its PowerBook line of notebooks, Apple Computer even has a wireless module that costs just $99, a price we expect most vendors to hit within 12 months. 9. Performance Wireless performance has nearly quadrupled over solutions based on proprietary or even 2-Mbps products using 802.11. Single-card performance can reach 6 Mbps, which is more than sufficient for the average business user. Much of this is thanks to the 802.11b high-rate standards body, which was driven primarily by Lucent and Harris. The 802.11b standard uses a technology called CCK (complimentary code keying) to encode the wireless data in a format that fits within the 802.11 DSSS (direct-sequence spread-spectrum) FCC rules. CCK is what allows these wireless devices to operate at 11 Mbps. Of course, CCK is not without its trade-offs; 11-Mbps products have significantly shorter range than their 2-Mbps counterparts. Fortunately, most vendors have implemented 802.11b products that drop back to 5.5 Mbps, 2 Mbps and 1 Mbps as range increases. As you inspect our performance charts (see graphics from main story), it is easy to identify where the cards under test dropped down to lower rates to support increased range. 8. Interoperability The 802.11b high-rate wireless standard is the best thing ever to happen to the industry. In our labs, we found that every one of the products we tested was capable of interoperating with products from competing vendors. The fact that we needed no special engineering support to make any of these products work together tells us that this technology has finally jelled. Rather than 11 vendors delivering 11 wireless products, there is one industry capable of delivering a wireless Ethernet solution. The efforts of the IEEE and the Wireless Ethernet Compatibility Alliance (WECA) and work being done at the University of New Hampshire are making wireless interoperability a nonissue. The work of these groups guarantees 802.11b will be the future of high-speed wireless. Without these groups and participation of the wireless networking vendors en masse, 802.11b would just be another shot-in-the-dark technology. WECA's WiFi (Wireless Fidelity) branding scheme is your guarantee that the wireless products you buy will be interoperable. 7. DS Reigns Over FH There is an almost religious war raging between the DS (direct sequence) and FH (frequency hopping) camps. However, because of the technology used in 802.11b, only DS solutions can operate at 11 Mbps. Fortunately, DSSS offers superior range and performance, and today's technology makes it affordable. DS technology uses a chipping code to spread a signal across a larger chunk of spectrum. A typical 2-Mbps DS system uses 11 chips to spread its signal, resulting in about 22 MHz of spectrum utilized. Note that there's 83.5 MHz of bandwidth, so you can get three clean DS channe