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Wireless Networking IEEE 802.11 Standards Module-03B

Wireless Networking IEEE 802.11 Standards Module-03B. Jerry Bernardini Community College of Rhode Island . Presentation Reference Material. CWNA Certified Wireless Network Administration Official Study Guide (PWO-104), David Coleman, David Westcott, 2009, Chapter-5

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Wireless Networking IEEE 802.11 Standards Module-03B

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  1. Wireless NetworkingIEEE 802.11 StandardsModule-03B Jerry Bernardini Community College of Rhode Island Wireless Networking J. Bernardini

  2. Presentation Reference Material • CWNA Certified Wireless Network Administration Official Study Guide (PWO-104), David Coleman, David Westcott, 2009, Chapter-5 • http://www.ieee802.org/11/ • http://en.wikipedia.org/wiki/IEEE_802.11 Wireless Networking J. Bernardini

  3. Wireless Networking J. Bernardini

  4. IEEE 802.11 Standards • Institute of Electrical and Electronic Engineers (IEEE) a professional society activity to establish standards • Hierarchical documents using clauses and sub-clauses • Task Groups (TGb, TGa, …) are used to study topics • Other Task Groups include: Ethernet, 802.3, 802.5, 802.15 • Task Groups designated by letters; a, b, g, n … • Defines wireless technology at Physical (PHY) and MAC sub- layer of Data link layer • Upper layer not addressed except of QoS Wireless Networking J. Bernardini

  5. 802.11-1997 (802.11 legacy) • Original version of the standard IEEE 802.11, released in June1997 and clarified in 1999 • ISM 2.4 GHz. band • Forward correcting codes code. • Infrared operating at 1 Mbps • Frequency Hopping Spread Spectrum (FHSS); at 1, 2 Mbps • Direct Sequence Spread Spectrum (DSSS); at 1, 2 Mbps • Legacy 802.11 with direct-sequence spread spectrum was rapidly supplanted and popularized by 802.11b. • Standard revised in 1999, 2003, 2007 Wireless Networking J. Bernardini

  6. IEEE 802.11 b • Defined as High-Rate DSS (HR-DSS) and Clause 18 devices • Uses 2.4 GHz ISM band • Support data rates of 1, 2, 5.5, 11 Mbps • Phase modulation and encoding spread spectrum • Complementary Code Keying (CCK) and Barker Coding • Manufacture dependent backward compatibility • Interference from other products operating in the 2.4 GHz band; microwave ovens, Bluetooth devices, baby monitors and cordless telephones Wireless Networking J. Bernardini

  7. IEEE 802.11 a • IEEE standard in 1999 (same year as 802.11b) • Uses UNII 5 GHz band – less crowded that 2.4 GHz band • Updated in Clause 17 802.11-2007 • Orthogonal Frequency Division Multiplexing (OFDM) used instead of DSSS • Supports 6, 9,12, 18, 24, 36, 54 Mbps • Not all vendors support all rates • Not compatible with 802.11b,802.11g and legacy 802.11 • Simultaneous operation with 802.11b,802.11g • Originally not adapted because of high frequency component costs Wireless Networking J. Bernardini

  8. IEEE 802.11 g • 2003 standard (Clause 19) for 2.4 GHz band • Referred to as Extended Rate Physical (ERP) • OFDM based and the same as 802.11a • Backward compatibility with 802.11b (ERP-DSSS/CCK) • Supports 6, 9, 12, 18, 24, 36, 48, 4 Mbps • Rapidly adopted by consumers because of speed , • Dual-band 802.11a/b, dual-band/tri-mode and b/g in a single adapter card and AP are available. • Like 802.11b, 802.11g devices suffer interference from other 2.4 GHz products • Equipment must support three modes and protection mechanism: • B-only mode • G-only mode • B/G-mode Wireless Networking J. Bernardini

  9. IEEE 802.11 n • Started in 2004, final ratification October 2009 (textbook still lists as draft) • Defined as High Throughput (HT) ( Clause 20) • Major goal: increase throughput over 802.11a/b/g • Backward compatible to 802.11a/b/g • Supports speeds over 100 Mbps • Multiple-Input-Multiple-Output (MIMO) to compensate for multipath • Requires multiple antennas and dual radios for full standard • Many other newer features to be covered later • Even before final ratification WiFi Alliance certified 802.11n draft 2 • Must support multiple modes and protection mechanism: • N-only mode (Greenfield mode) • A-only mode • B/G-mode Wireless Networking J. Bernardini

  10. IEEE 802.11 d • 2001 standard International use and (country-to-country) roaming extensions • Defines differences between countries country codes , frames and beacons • Configuration parameters for FHSS (legacy use) • Details in 802.11-2007 clause 9.8 Wireless Networking J. Bernardini

  11. IEEE 802.11 F • An attempt to standardize wireless roaming • Vendors did not adapt the recommendations uniformly • Roaming will probably not work between vendor • Two things must happen for roaming • New AP must inform original AP a station is associating with the new AP and want buffered packets • Original AP must forward buffered packets to new AP • 802.11F never ratified and withdrawn in February 2006 • Light AP’s and WLAN controller minimize the need for inter-vendor roaming standard • Recommend practice is to use Inter-Access Point Protocol (IAPP) Wireless Networking J. Bernardini

  12. IEEE 802.11 h • Standard to define mechanism for Dynamic Frequency Selection (DFS) • Standard to define mechanism for Transmit Power Control (TPC) • Radar detection and WLAN control • Increased frequency space in UNII-2 band • Amendent now in 11.8 and 11.9 of 802.11-2007 Wireless Networking J. Bernardini

  13. IEEE 802.11 i • 802.11 from 1997 to 2004 only support 64-bit Wired Equivalent Privacy (WEP) encryption • WEP was cracked in 2003- no long recommended • 802.11i improves wireless security • Stronger encryption methods • Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP) and Advanced Encryption Standard (AES) • Temporal Key Integrity Protocol (TKIP) • RC-4 Stream cipher • Extensible Authentication Protocol (EAP) • WiFi Protection Access 2 (WAP2) • Wireless Security is important - CWSP Wireless Networking J. Bernardini

  14. IEEE 802.11 j • Standard to gain Japanese regulatory approval for MAC and 802.11a PHY improvements • Japan 802.11a radio cards to operate at 5.15 to 5.25 GHz and 4.9 to 5.091 GHz • Option for Japan to operate OFDM with 10 MHz spacing, increasing number of bandwidth rates Wireless Networking J. Bernardini

  15. IEEE 802.11 e • Amendment for Quality of Service (QoS) • Voice and Video are not latency and jitter tolerant • Voice over IP (VoWIP) and VoWiFi • Defines layer two MAC methods to meet QoS • Distributed Coordination Function (DCF)– random method to determine which application runs first • Point Coordination Function (PCF) –Polls clients for appilcation priority • Hybrid Coordination Function Control Channel Access (HCCA)- AP is given ability to set station priority • Wi-Fi Alliance Wi-Fi Multimedia (WMM) Wireless Networking J. Bernardini

  16. IEEE 802.11 k Wireless Networking J. Bernardini

  17. IEEE 802.11 r Wireless Networking J. Bernardini

  18. IEEE 802.11 m Wireless Networking J. Bernardini

  19. IEEE 802.11 p Wireless Networking J. Bernardini

  20. IEEE 802.11 s Wireless Networking J. Bernardini

  21. IEEE 802.11 T Wireless Networking J. Bernardini

  22. IEEE 802.11 u Wireless Networking J. Bernardini

  23. IEEE 802.11 v Wireless Networking J. Bernardini

  24. IEEE 802.11 w Wireless Networking J. Bernardini

  25. IEEE 802.11 y Wireless Networking J. Bernardini

  26. IEEE 802.11 z Wireless Networking J. Bernardini

  27. IEEE 802.11 aa Wireless Networking J. Bernardini

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