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Wireless LAN Standards
2005-02-14 (updated: 2009-11-09) by Philip
Tags: WLAN, Wireless, Wi-Fi, Standard, IEEE, Frequency, WEP, WPA, WPA2, MIMO, Bluetooth, HomeRF, SSL, VPN, LAN
Different wireless technologies define a rapidly emerging area of growth in networking. The need for mobile computing, wireless peripherals, voice and messaging, hand-held and other internet-enabled devices, easy home networking, media streaming, and cost-effective networking solutions in general have driven the recent development of a number of wireless networking standards. All those wireless technologies target different niches in the WLAN market, work over different frequencies, and only a few are compatible with each other. The quick WLAN reference table below will help differentiate between the different wireless networking standards in use today. | IEEE Standard | Speed (max) | Frequency | Transmission Method | Security | Details | | 802.11 legacy | 2 Mbps | 2.4 GHz | DSSS, FHSS | WEP, WPA | IEEE specification extended into 802.11b | | 802.11a | 54 Mbps | 5.0 GHz | OFDM | WEP, WPA | Wi-Fi Alliance standard, 12 non-overlapping channels (each 20 MHz wide). Less potential for RF interference at 5 GHz than 2.4 GHz. Shorter range than, and not interoperable with 802.11b/g. Average actual throughput 10-25 Mbps. | 802.11b
(Wi-Fi) | 11 Mbps | 2.4 GHz | DSSS, HR-DSSS | WEP, WPA | Wi-Fi Alliance standard. 11 channels (each 22 MHz wide, only 3 non-overlapping, 14 usable channels outside the U.S.). Average actual throughput 5 Mbps. | | 802.11g | 54 Mbps | 2.4 GHz | DSSS, HR-DSSS, OFDM | WEP, WPA | Wi-Fi Alliance standard, 11 channels (each 22 MHz wide, only 3 non-overlapping, 14 usable channels outside the U.S.). Compatible with 802.11b, with improved speed and security. Will eventually replace 802.11b. Uses additional OFDM modulation technique above 20 Mbps. Average actual throughput 10-25 Mbps. | | 802.11n | 200+ Mbps | 2.4/5 GHz | MIMO | WPA2 ??? | Emerging Wi-Fi Alliance standard (scheduled to be complete by the end of 2006), backward compatible with 802.11a/b/g. It is to achieve that by adding MIMO (multiple-input, multiple-output), using multiple antennas. Average throughput of 100+ Mbps. | | Bluetooth | 2 Mbps | 2.45 GHz | FHSS | PPTP, VPN or SSL | No native TCP/IP support. Best suited to connect PDAs, cell phones and peripheral devices at short distances. | | HomeRF | 10 MBps | 2.4 GHz | FHSS | 56-bit encryption, separate IPs for each network. | No longer supported. 150 feet range, intended for home use. Reserves part of available bandwidth for voice services. Responds well to interference because of FHSS. | | HiperLAN/1 | 20 MBps | 5 GHz | CSMA/CA | individual authentication and per-sesison encryption keys | Only used in Europe. Ad-hoc WLAN, requires no configuration or central controller. | | HiperLAN/2 | 54 MBps | 5 GHz | OFDM | individual authentication and per-session encryption keys | Only used in Europe.It can carry ATM cells, IP packets, Firewire packets, as well as digital voice (cellular phones). |
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