1. Wireless Networking IEEE 802.11 Standards Module-03B Jerry Bernardini Community College of Rhode Island 6/27/2015Wireless Networking J. Bernardini1

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 6/27/2015Wireless Networking J. Bernardini2

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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 6/27/2015Wireless Networking J. Bernardini4

5. 802.11-1997 (802.11 legacy) 6/27/2015Wireless Networking J. Bernardini5 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

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 6/27/2015Wireless Networking J. Bernardini6

7. IEEE 802.11 a 6/27/2015Wireless Networking J. Bernardini7 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

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 6/27/2015Wireless Networking J. Bernardini8

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 6/27/2015Wireless Networking J. Bernardini9

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 6/27/2015Wireless Networking J. Bernardini10

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) 6/27/2015Wireless Networking J. Bernardini11

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 6/27/2015Wireless Networking J. Bernardini12

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 6/27/2015Wireless Networking J. Bernardini13

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 6/27/2015Wireless Networking J. Bernardini14

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) 6/27/2015Wireless Networking J. Bernardini15

16. IEEE 802.11 k 6/27/2015Wireless Networking J. Bernardini16

17. IEEE 802.11 r 6/27/2015Wireless Networking J. Bernardini17

18. IEEE 802.11 m 6/27/2015Wireless Networking J. Bernardini18

19. IEEE 802.11 p 6/27/2015Wireless Networking J. Bernardini19

20. IEEE 802.11 s 6/27/2015Wireless Networking J. Bernardini20

21. IEEE 802.11 T 6/27/2015Wireless Networking J. Bernardini21

22. IEEE 802.11 u 6/27/2015Wireless Networking J. Bernardini22

23. IEEE 802.11 v 6/27/2015Wireless Networking J. Bernardini23

24. IEEE 802.11 w 6/27/2015Wireless Networking J. Bernardini24

25. IEEE 802.11 y 6/27/2015Wireless Networking J. Bernardini25

26. IEEE 802.11 z 6/27/2015Wireless Networking J. Bernardini26

27. IEEE 802.11 aa 6/27/2015Wireless Networking J. Bernardini27