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Wireless clarification and info

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    Wireless clarification and info

    Quick Reference

    To clear up some wireless information here you go for your pleasure reading:

    From John Dvorak, PC Magazine Sep 5 issue (sorry I don't have the proper citation)
    Wi-Fi on the Moon Dept.: I've begun a long-term look at 802.11 gear for long-distance connectivity. Although there are legal limitations on how much wattage you can use for 802.11, most of the equipment sold to consumers and small businesses is far under that limit. Most consumer 802.11b gear is 33 milliwatts, for example. The FCC allows up to one full watt of power.
    The only company promoting wattage seems to be SMC Networks. As far as I can tell, it is the only one even mentioning the radio wattage on the box. Nobody else wants to talk about it. See if you can even find the wattage specification on that laptop with built-in 802.11. SMC makes a PCMCIA card-the SMC2532W-with a 200-milliwatt radio. It has a range of half a mile with no special antenna. This should be the perfect addition to the wardriver's arsenal. It sells everywhere for about $60.
    Now there may be some good public-policy reasons for not promoting wattage. In my discussion with SMC engineers about wattage, the notion of adding a dangerous linear amp to the radio came up. This is what was used during the CB radio fad when bozos were blowing out channels with amplified signals. The problem with 802.11b is that the frequency is the same as that of a microwave oven. You start amplifying the signal and, as one engineer said, "Someone is going to get hurt!"-or cooked, as it were. "Gee, Honey, isn't it getting a little warm in the house?"

    IEEE reference

    IEEE 802 General Information
    · IEEE 802 Working Group & Executive Committee Study Group Home Pages
    · 802.11; including information on: 802.11a | 802.11b | 802.11e | 802.11g | 802.11i
    · 802.2
    · 802.3
    · 802.15
    · 802.16
    IEEE 802.11
    802.11 is a family of specifications for wireless local area networks (WLANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE).There are currently four specifications in the family. 802.11e and 802.11i are scheduled for approval in 2004.802.11802.11a802.11b802.11gAll four use the Ethernet protocol and CSMA/CA (carrier sense multiple access with collision avoidance) for path sharing.IEEE 802.11 - applies to wireless LANs and provides 1 or 2 Mbps transmission in the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS). Learn more about 802.11IEEE 802.11a - an extension to 802.11 that applies to wireless LANs and provides up to 54 Mbps in the 5GHz band; but most commonly, communications takes place at 6 Mbps, 12 Mbps, or 24 Mbps. 802.11a uses an orthogonal frequency division multiplexing encoding scheme rather than FHSS or DSSS. The specification applies to wireless ATM systems and is used in access hubs.IEEE 802.11b - often called Wi-Fi - is backward compatible with 802.11. The modulation used in 802.11 has historically been phase-shift keying (PSK). The modulation method selected for 802.11b is known as complementary code keying (CCK), which allows higher data speeds and is less susceptible to multipath-propagation interference.IEEE 802.11e - first wireless standard that spans home and business environments. It adds quality-of-service (QoS) features and multimedia support to the existing IEEE 802.11b and IEEE 802.11a wireless standards, while maintaining full backward compatibility with these standards. QoS and multimedia support are critical to wireless home networks where voice, video and audio will be delivered. Broadband service providers view QoS and multimedia-capable home networks as an essential ingredient to offering residential customers video on demand, audio on demand, voice over IP and high-speed Internet access. (From NetworkWorldFusion)IEEE 802.11g - applies to wireless LANs and provides 20+ Mbps in the 2.4 GHz band.This is the most recently approved standard and offers wireless transmission over relatively short distances at up to 54 megabits per second (Mbps) compared with the 11 megabits per second of the 802.11b standard. Like 802.11b, 802.11g operates in the 2.4 GHz range and is thus compatible with it.IEEE 802.11i - adds the Advanced Encryption Standard (AES) security protocol to the 802.11 standard for wireless LANs. Security has been a primary concern for IT managers reluctant to deploy wireless networks, but AES is a stronger level of security than found in the current Wi-Fi Protected Access security standard. (From NetworkWorldFusion)