ISO/IEC DIS 8802-11
IEEE P802.11/D9.0, 16 Nov. 1998 LOCAL AND METROPOLITAN AREA NETWORKS: WIRELESS LAN
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Copyright © 1998 IEEE. All rights reserved.
This is an unapproved IEEE Standards Draft, subject to change.
7.1.1 Conventions ............................................................................................................... 34
7.1.2 General frame format................................................................................................. 34
7.1.3 Frame fields ...............................................................................................................35
7.2 Format of individual frame types.............................................................................................41
7.2.1 Control frames ........................................................................................................... 41
7.2.2 Data frames................................................................................................................43
7.2.3 Management frames................................................................................................... 45
7.3 Management frame body components ..................................................................................... 50
7.3.1 Fixed fields................................................................................................................. 50
7.3.2 Information elements ................................................................................................. 55
8. Authentication and privacy................................................................................................................ 60
8.1 Authentication services ............................................................................................................ 60
8.1.1 Open System authentication ...................................................................................... 60
8.1.2 Shared Key authentication......................................................................................... 61
8.2 The Wired Equivalent Privacy (WEP) algorithm .................................................................... 62
8.2.1 Introduction................................................................................................................ 62
8.2.2 Properties of the WEP algorithm............................................................................... 63
8.2.3 WEP theory of operation ........................................................................................... 63
8.2.4 WEP algorithm specification..................................................................................... 65
8.2.5 WEP Frame Body expansion..................................................................................... 65
8.3 Security-Related MIB attributes............................................................................................... 66
8.3.1 Authentication-Related MIB attributes...................................................................... 66
8.3.2 Privacy-Related MIB attributes ................................................................................. 66
9. MAC sublayer functional description................................................................................................ 71
9.1 MAC architecture..................................................................................................................... 71
9.1.1 Distributed coordination function (DCF)................................................................... 71
9.1.2 Point coordination function (PCF)............................................................................. 71
9.1.3 Coexistence of DCF and PCF.................................................................................... 72
9.1.4 Fragmentation/defragmentation overview................................................................. 72
9.1.5 MAC data service ...................................................................................................... 73
9.2 DCF.......................................................................................................................................... 73
9.2.1 Carrier sense mechanism ........................................................................................... 74
9.2.2 MAC-Level acknowledgments.................................................................................. 74
9.2.3 Interframe space (IFS) ............................................................................................... 75
9.2.4 Random backoff time................................................................................................. 76
9.2.5 DCF access procedure................................................................................................ 77
9.2.6 Directed MPDU transfer procedure........................................................................... 83
9.2.7 Broadcast and multicast MPDU transfer procedure .................................................. 84
9.2.8 ACK procedure.......................................................................................................... 84
9.2.9 Duplicate detection and recovery............................................................................... 84
9.2.10 DCF timing relations.................................................................................................. 85
9.3 PCF........................................................................................................................................... 87
9.3.1 CFP structure and timing ........................................................................................... 88
9.3.2 PCF access procedure ................................................................................................ 89
9.3.3 PCF transfer procedure .............................................................................................. 90
9.3.4 Contention-Free polling list....................................................................................... 93
9.4 Fragmentation........................................................................................................................... 94
9.5 Defragmentation....................................................................................................................... 95
9.6 Multirate support...................................................................................................................... 96
9.7 Frame exchange sequences ...................................................................................................... 97
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