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Which Wireless Standard is best for you?. 802.11a 802.11b 802.11g. Presented by: David F. Soll Vice President Advanced Technology dsoll@omicron.com. Agenda. IEEE 802.11 Wi-Fi Alliance Practical Considerations Adapter Types Intel Centrino Wi-Fi Zones Conclusions Questions.
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Which Wireless Standard is best for you? 802.11a 802.11b 802.11g Presented by: David F. Soll Vice President Advanced Technology dsoll@omicron.com
Agenda • IEEE 802.11 • Wi-Fi Alliance • Practical Considerations • Adapter Types • Intel Centrino • Wi-Fi Zones • Conclusions • Questions
IEEE 802.11 • Institute of Electrical and Electronic Engineers (IEEE) • LAN/MAN Standards Committee (802) • LAN = Local Area Network • MAN = Metropolitan Area Networks • 802 is sub-divided into working groups • Use a decimal point to designate working group
IEEE 802.11 • Active (Still in development) 802 Working Groups • 802.1 High Level Interface (HILI) Working Group • 802.3 CSMA/CD Working Group • 802.11 Wireless LAN (WLAN) Working Group • 802.15 Wireless Personal Area Network (WPAN) Working Group • 802.16 Broadband Wireless Access (BBWA) Working Group • 802.17 Resilient Packet Ring (RPR) • 802.18 Radio Regulatory Technical Advisory Group • 802.19 Coexistence Technical Advisory Group • 802.20 Mobile Wireless Access Working Group
IEEE 802.11 • 802.11a • Approved as a standard September 1999 • 54 MB • 5 GHz band
IEEE 802.11 • 802.11b • Approved as a standard September 1999 • Updates to standard approved in October 2001 • 11 MB • 2.4 GHz band
IEEE 802.11 • 802.11d • Approved as a standard June 2001 • Provide options for wireless access where 802.11a or 802.11b were not legal • Some countries do not allow consumer transmissions on the bands allocated for 802.11
IEEE 802.11 • 802.11e • Not yet an approved standard • Quality of Service (QOS) protocols for 802.11 • Designed to provide QOS required for: • Voice • Video • Media Stream Distribution
IEEE 802.11 • 802.11F • Not yet an approved standard • Trial-Use Recommended Practice for Multi-Vendor Access Point Interoperability
IEEE 802.11 • 802.11g • Not yet an approved standard • Final acceptance is expected in June 2003 • Develop higher speeds for 802.11b • 54 MB • 2.4 GHz band
IEEE 802.11 • 802.11h • Amendment to 802.11a • To add indoor and outdoor channel selection for 5GHz license exempt bands in Europe • To enhance channel energy measurement and reporting mechanisms to improve spectrum and transmit power management • Enables regulatory acceptance in some countries
IEEE 802.11 • 802.11i • Not yet an approved standard • Enhance Security for 802.11 communications • This is not WEP, but is more complex and more secure
IEEE 802.11 • 802.11j • Obtain Japanese regulatory approval • Additionally operate in newly available Japanese 4.9 GHz and 5 GHz bands.
IEEE 802.11 • 802.11k • Radio Resource Measurement of Wireless LANs • Provide measurements and other information in order to manage 802.11 services from an external source
IEEE 802.11 • The Bottom Line: • 802.11a • 54 MB theoretical transfer rate • 5 GHz Band • 802.11b • 11 MB theoretical transfer rate • 2.4 GHz Band • 802.11g • 54 MB theoretical transfer rate • 2.4 GHz Band
Wi-Fi Alliance • Nonprofit International Association • Formed in 1999 • Certifies interoperability of wireless Local Area Network products based on IEEE 802.11 • 176 member companies • 611 products have received Wi-Fi certification • Began certification March 2000
Wi-Fi Alliance • Will not certify un-approved standards • ie: 802.11g • Announced that testing of 802.11g is expected to start in July • Web site of all certified equipment: • http://www.weca.net
Practical Considerations • Popularity • 802.11b is the most popular by far • It was the first out of the gate • 802.11a does not show signs of catching up with 802.11b • Tends to be a little more expensive than 802.11b • 802.11g may replace 802.11b as the most popular someday, but not yet • Costs should be comparable to 802.11b
Practical Considerations • Speed • 802.11a is a clear winner in the speed category • Even though 802.11a and 802.11g are both rated at 54 MB theoretical, 802.11a out performs 802.11g consistently in actual tests
Practical Considerations • Distance • The higher the frequency, the more difficult it is to penetrate objects (ie: walls) • 2.4 GHz is likely to travel further through walls than 5 GHz • 802.11b and 802.11g use 2.4 GHz • 802.11a uses 5 GHz • 802.11a uses speed throttling to improve distance • The further away (the weaker the signal), the slower the data throughput
Practical Considerations • Interference • 802.11b and 802.11g use the same 2.4 GHz band as: • Cordless telephones • Bluetooth • 802.11a uses 5 GHz • Some new cordless phones now use 5 GHz
Practical Considerations • Interference (cont’d.) • 802.11a has 19 channels • All channels are non-overlapping • 802.11b has 11 channels but … • Only 3 non-overlapped channels
Practical Considerations • Product Availability and Price • 802.11b is both cheapest and most available • Some products (such as a wireless bridge) are only available in 802.11b
Adapter Types • Cardbus • Intended for Notebook computers • PCI • Intended for Desktop computers • Early PCI adapters were simply PCI to Cardbus converters and required a Cardbus adapter • Most of the newer adapters for PCI are now native PCI adapters • USB • Work fine for either Notebook or Desktop
Adapter Types • 802.11b only • Single Band (2.4 GHz) • 802.11a only • Single Band (5 GHz) • 802.11 a and b • Dual band (2.4 GHz and 5 GHz) • Connect to either 802.11a or 802.11b • 802.11g • Single Band (2.4 GHz) • Typically supports 802.11b also
Intel Centrino • Intel’s new brand name of a combination of chips including CPU and wireless communications • New CPU – Pentium-M • Not to be confused with Pentium 4-M • Complete New Design • Lower Power • Higher Speed • ie: Pentium-M 1.4 GHz outperformed a P4-M 2.4 GHz in one set of tests by 38%
Intel Centrino • Wireless Capabilities only include 802.11b • Intel claims: • 802.11a support is “months” away • 802.11g will be available by the end of the year
Wi-Fi Zones • Areas where Wi-Fi Access is provided • Often called Wi-Fi hot-spots • The Wi-Fi Alliance provides free Wi-Fi Zone registration for providers • http://www.wi-fizone.org/
Wi-Fi Zones • Zones in Philadelphia • Loews Philadelphia Hotel • Four Seasons Hotel • Wyndham Philadelphia • Embassy Suites Hotel • Radisson Plaza Warwick Hotel • Embassy Suites (Philadelphia Airport)
Zones in New Jersey Residence Inn Saddle River Embassy Suites Hotel - Piscataway - Somerset Embassy Suites Hotel - Secaucus - Meadowlands HI-Totowa Hilton Newark Gateway Parsippany Hilton Radisson Inn Englewood Summerfield Suites Parsippany Whippany Summerfield Suites Mount Laurel Summerfield Suites Princeton Summerfield Suites Somerset Inn at Somerset Hills Sunrise Suites Hotel Summerfield Suites Bridgewater Sierra Suites Piscataway Somerset Marriott Hotel Westin Morristown Courtyard by Marriott Wyndham Newark Airport Rivendell - Edison Square One Morristown Deli Newark Airport Wi-Fi Zones
Conclusions • 802.11a is the speed king • Higher cost • Dual-band cards provide 802.11b compatibility • Good if you have a local server, but the extra speed won’t help if your connection to the internet is under 2 MB (ie: cable and DSL)
Conclusions • 802.11b is the current leader • Cheapest • Most Popular • Most Compatible • Most Available • More Products Available • More “hot-spots” available
Conclusions • 802.11g is a good option (after July) • Most will be backward compatible with 802.11b • Should see prices comparable to 802.11b • Higher speed than 802.11b
Which Wireless Standard is best for you? 802.11a 802.11b 802.11g http://mywebpages.comcast.net/soll Presented by: David F. Soll Vice President Advanced Technology dsoll@omicron.com