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Assessing the standards in wireless

Assessing the standards in wireless. Neil Pawley npawley@gmail.com. Contents. Lots and lots of standards Alphabet soup The 802 family Range and mobility Issues Conclusion. Wide family of specifications (a, b, d, h, I, j etc) Wireless Local Area Network (WLAN)

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Assessing the standards in wireless

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  1. Assessing the standards in wireless Neil Pawley npawley@gmail.com

  2. Contents • Lots and lots of standards • Alphabet soup • The 802 family • Range and mobility • Issues • Conclusion

  3. Wide family of specifications (a, b, d, h, I, j etc) Wireless Local Area Network (WLAN) Range of frequencies and speeds Popularly known as WiFi 802.11x Bluetooth leads the way Wireless Personal Area Network (WPAN) 802.15 Broadband Wireless Access (BWA) WiMAX Not as simple as it sounds Still a lot to do 802.16x Mobile Broadband Wireless Access (MBWA) Potential conflict 802.20 Lots and lots of standards

  4. Alphabet soup IEEE – Institute of Electrical & Electronics Engineers OFDM – Orthogonal Frequency Division Multiplexing TDMA – Time division Multiple Access MAC – Media Access Control layer WEP – Wired Equivalent Privacy IPSec – Internet Protocol Security WPA – WiFi Protected Access OFDM – Orthogonal Frequency Division Multiplexing WMAN – Wireless Metropolitan Area Network BWA – Broadband Wireless Access

  5. 802.11a • Up to 54 Mbps • 5.7 – 5.8 GHz • Interference free • Good for office setting 802.11b • Up to 11 Mbps • 2.4 GHz • Backwards compatible • The one most people think of 802.11d • Same as 802.11b • Allows users to modify transmission band 802.11x WiFi

  6. 802.11h (not formalised) • Update of 802.11a specification • Resolve interference with military and medical 802.11i • Improved encryption for 802.11a, b and g • Government requirements • Special chip required 802.11j (not formalised) • Incorporate Japanese specialist extensions 802.11x WiFi

  7. 802.15 - Bluetooth • Wireless Personal Area Network (WPAN) • Everything on the desk • Bluetooth is only one flavour • 30ft transmission radius • Proximity connection • Selective lock out

  8. 802.16-2004 WiMAX • Controlled by IEEE and WiMAX Forum • Wireless (Wi) Microwave Access (MA) • BWA – Broadband Wireless Access • Static • Building to building • One to many • Very similar to WiFi

  9. NLOS 2-11 Ghz LOS 66 Ghz LOS 66 Ghz Two proposed transport methodologies Traditional • Cabled to broadcast antenna • Point-to-multipoint (P2MP) • Customer Premises Units (CPEs) • Limited in scalability • Final link to 802.11 • Offers cheap expansion of broadband • Not required in cabled areas

  10. NLOS 2-11 Ghz LOS 66 Ghz Two proposed transport methodologies Mesh • Node to node • Customer Premises Units (CPEs) • Non line of sight • Traffic routing • Fault tolerance • Load balancing • More users, more effective • Self-organising neighbourhood

  11. 802.16e Mobile WiMAX • IEEE have made it official (December 2005) • No guaranteed compatibility with 802.16-2004 • Maybe dual chip in future • Semi nomadic • Similar to early days of mobile phones • Only good for wandering around

  12. 802.20 • Mobile Broadband Wireless Access (MBWA) • Another 802.16e? • Mired in conflict • Frequencies below 3.5 GHz • Enable data transfer at speed • Travelling in a car or train • Isn’t this what 3G is trying to do?

  13. Don’t move 30 ft 54 Mbps 300 ft 100 Mbps 30 miles 16 Mbps 2 - 4 miles 2 Mbps 2 – 4 miles Range and mobility 802.15 802.11x 802.16 802.20 3G

  14. Issues • Further away, less bandwidth • More users, less bandwidth • Real time numbers smaller than manufacturers claims • Large overhead in wireless negotiation • Some of this is over 18 months away • Compromises in metropolitan mesh experiments • San Francisco • New Orleans • Dundee

  15. Conclusions • Massive collection of standards • Many still being worked on • Pick what you need • Don’t believe everything you read • When to take the plunge • What benefits can be realised

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