ISO/IEC 8802-11:1999/PDAM 2

DRAFT AMENDMENT ISO/IEC 8802-11:1999/DAM 2
Attributed to ISO/IEC JTC 1 by the Central Secretariat (see page ii)
Voting begins on Voting terminates on
2000-02-24 2000-08-24
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION � МЕЖДУНАРОДНАЯОРГАНИЗАЦИЯПОСТАНДАРТИЗАЦИИ � ORGANISATION INTERNATIONALE DE NORMALISATION
INTERNATIONAL ELECTROTECHNICAL COMMISSION � МЕЖДУНАРОДНАЯ ЭЛЕКТРОТЕХНИЧЕСКАЯ КОММИСИЯ � COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
Information technology — Telecommunications
and information exchange between systems — Local and
metropolitan area networks — Specific requirements —
Part 11:
Wireless LAN Medium Access Control (MAC) and Physical
Layer (PHY) specifications
AMENDMENT 2: Higher-speed physical layer extension
in the 2.4 GHz band
Technologies de l'information — Télécommunications et échange d'information entre systèmes — Réseaux locaux
et métropolitains — Exigences spécifiques —
Partie 11: Spécifications pour le contrôle d'accès au support et la couche physique
AMENDEMENT 2: Extension de la couche physique à grande vitesse dans la bande 2,4 GHz
ICS 35.110
In accordance with the provisions of Council Resolution 21/1986 this DIS is circulated in the
English language only.
Conformément aux dispositions de la Résolution du Conseil 21/1986, ce DIS est distribué en
version anglaise seulement.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE REFERRED TO
AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO WHICH
REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
International Organization for Standardization, 2000
©
International Electrotechnical Commission, 2000

ISO/IEC 8802-11/DAM 2
"FAST-TRACK"
NOTEFROMITTF
This draft International Standard is submitted for JTC 1 national body vote under the Fast-Track
Procedure.
In accordance with Resolution 30 of the JTC 1 Berlin Plenary 1993, the proposer of this document
recommendsassignmentof ISO/IEC 8802-11/DAM2toJTC1/SC 6.
"FAST-TRACK"PROCEDURE
1 Any P-member and any Category A liaison organization of ISO/IEC JTC 1 may propose that an
existing standard from any source be submitted directly for vote as a DIS. The criteria for
proposing an existing standard for the fast-track procedure are a matter for each proposer to
decide.
2 Theproposalshallbereceived by theITTFwhich willtakethefollowing actions.
2.1 To settle the copyright and/or trade mark situation with the proposer, so that the proposed text
can befreely copied and distributed within JTC1withoutrestriction.
2.2 To assess in consultation with the JTC 1 secretariat which SC is competent for the subject
covered by the proposed standard and to ascertain that there is no evident contradiction with other
InternationalStandards.
2.3 To distribute the text of the proposed standard as a DIS. In case of particularly bulky
documentstheITTFmay demand thenecessary numberof copiesfromtheproposer.
3 The period for combined DIS voting shall be six months. In order to be accepted the DIS must be
supported by 75 % of the votes cast (abstention is not counted as a vote) and by two-thirds of the P-
membersvoting of JTC1.
4 At the end of the voting period, the comments received, whether editorial only or technical, will
bedealtwith by aworking group appointed by thesecretariatof therelevantSC.
5 If, after the deliberations of this WG, the requirements of 3 above are met, the amended text
shall be sent to the ITTF by the secretariat of the relevant SC for publication as an International
Standard.
If itisimpossibleto agree to a text meeting the above requirements, the proposal has failed and the
procedureisterminated.
In either casetheWG shallprepareafullreportwhich willbecirculated by theITTF.
6 If theproposed standard isaccepted and published,itsmaintenancewillbehandled by JTC1.
ii
IEEE Std 802.11b-1999
(Supplement to
ANSI/IEEE Std 802.11, 1999 Edition)
Supplement to IEEE Standard for
Information technology—
Telecommunications and information exchange
between systems—
Local and metropolitan area networks—
SpeciÞc requirements—
Part 11: Wireless LAN Medium Access Control
(MAC) and Physical Layer (PHY) speciÞcations:
Higher-Speed Physical Layer Extension in the
2.4 GHz Band
Sponsor
LAN/MAN Standards Committee
of the
IEEE Computer Society
Approved 16 September 1999
IEEE-SA Standards Board
Abstract: Changes and additions to IEEE Std 802.11, 1999 Edition are provided to support the
higher rate physical layer (PHY) for operation in the 2.4 GHz band.
Keywords: 2.4 GHz, high speed, local area network (LAN), radio frequency (RF), wireless
The Institute of Electrical and Electronics Engineers, Inc.
3 Park Avenue, New York, NY 10016-5997, USA
All rights reserved. Published 20 January 2000. Printed in the United States of America.
Print: ISBN 0-7381-1811-7 SH94788
PDF: ISBN 0-7381-1812-5 SS94788
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written permission of the publisher.

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Introduction
[This introduction is not part of IEEE Std 802.11b-1999, Supplement to IEEE Standard for Information technology—
Telecommunications and information exchange between systems—Local and metropolitan area networks—SpeciÞc
requirements—Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) speciÞcations:
Higher-Speed Physical Layer Extension in the 2.4 GHz Band.]
This standard is part of a family of standards for local and metropolitan area networks. The relationship
between the standard and other members of the family is shown below. (The numbers in the Þgure refer to
IEEE standard numbers.)
802.2 LOGICAL LINK CONTROL
DATA
802.1 BRIDGING
LINK
LAYER
802.3 802.4 802.5 802.6 802.9 802.11 802.12
MEDIUM MEDIUM MEDIUM MEDIUM MEDIUM MEDIUM MEDIUM
ACCESS ACCESS ACCESS ACCESS ACCESS ACCESS ACCESS
802.3 802.4 802.5 802.6 802.9 802.11 802.12
PHYSICAL
PHYSICAL PHYSICAL PHYSICAL PHYSICAL PHYSICAL PHYSICAL PHYSICAL LAYER
* Formerly IEEE Std 802.1A.
This family of standards deals with the Physical and Data Link layers as deÞned by the International Organiza-
tion for Standardization (ISO) Open Systems Interconnection (OSI) Basic Reference Model (ISO/IEC
7498-1:1994). The access standards deÞne seven types of medium access technologies and associated physi-
cal media, each appropriate for particular applications or system objectives. Other types are under
investigation.
The standards deÞning the access technologies are as follows:
 IEEE Std 802 Overview and Architecture. This standard provides an overview to the family
of IEEE 802 Standards.
 ANSI/IEEE Std 802.1B LAN/MAN Management. DeÞnes an OSI management-compatible architec-
and 802.1k ture, and services and protocol elements for use in a LAN/MAN environment
[ISO/IEC 15802-2] for performing remote management.
 ANSI/IEEE Std 802.1D Media Access Control (MAC) Bridges. SpeciÞes an architecture and protocol
[ISO/IEC 15802-3] for the interconnection of IEEE 802 LANs below the MAC service boundary.
 ANSI/IEEE Std 802.1E System Load Protocol. SpeciÞes a set of services and protocol for those
[ISO/IEC 15802-4] aspects of management concerned with the loading of systems on IEEE 802
LANs.
 IEEE Std 802.1F Common DeÞnitions and Procedures for IEEE 802 Management Information
 ANSI/IEEE Std 802.1G Remote Media Access Control Bridging. SpeciÞes extensions for the intercon-
[ISO/IEC 15802-5] nection, using non-LAN communication technologies, of geographically sepa-
rated IEEE 802 LANs below the level of the logical link control protocol.
802.10 SECURITY
802 OVERVIEW & ARCHITECTURE*
802.1 MANAGEMENT
 ANSI/IEEE Std 802.2 Logical Link Control
[ISO/IEC 8802-2]
 ANSI/IEEE Std 802.3 CSMA/CD Access Method and Physical Layer SpeciÞcations
[ISO/IEC 8802-3]
 ANSI/IEEE Std 802.4 Token Passing Bus Access Method and Physical Layer SpeciÞcations
[ISO/IEC 8802-4]
 ANSI/IEEE Std 802.5 Token Ring Access Method and Physical Layer SpeciÞcations
[ISO/IEC 8802-5]
 ANSI/IEEE Std 802.6 Distributed Queue Dual Bus Access Method and Physical Layer SpeciÞca-
[ISO/IEC 8802-6] tions
 ANSI/IEEE Std 802.9 Integrated Services (IS) LAN Interface at the Medium Access Control and
[ISO/IEC 8802-9] Physical Layers
 ANSI/IEEE Std 802.10 Interoperable LAN/MAN Security
 IEEE Std 802.11 Wireless LAN Medium Access Control and Physical Layer SpeciÞcations
[ISO/IEC DIS 8802-11]
 ANSI/IEEE Std 802.12 Demand Priority Access Method, Physical Layer and Repeater SpeciÞca-
[ISO/IEC DIS 8802-12] tions
In addition to the family of standards, the following is a recommended practice for a common Physical
Layer technology:
 IEEE Std 802.7 IEEE Recommended Practice for Broadband Local Area Networks
The following additional working groups have authorized standards projects under development:
 IEEE 802.14 Standard Protocol for Cable-TV Based Broadband Communication Network
 IEEE 802.15 Wireless Personal Area Networks Access Method and Physical Layer
SpeciÞcations
 IEEE 802.16 Broadband Wireless Access Method and Physical Layer SpeciÞcations
iv Copyright © 2000 IEEE. All rights reserved.

Participants
At the time this standard was balloted, the 802.11 Working Group had the following membership:
Vic Hayes, Chair
Stuart J. Kerry, Vice Chair
Al Petrick, Co-Vice Chair
George Fishel, Secretary
Robert O'Hara, Chair and editor, 802.11-rev
Allen Heberling, State-diagram editor
Michael A. Fischer, State-diagram editor
Dean M. Kawaguchi, Chair PHY group
David Bagby, Chair MAC group
Naftali Chayat, Chair Task Group a
Hitoshi Takanashi, Technical Editor, 802.11a
John Fakatselis, Chair Task Group b
Carl F. Andren, Technical Editor, 802.11b
Chris D. Heegard
Jeffrey Abramowitz Frits Riep
Reza Ahy Robert Heile William Roberts
Keith B. Amundsen Juha T. Heiskala
Kent G. Rollins
James R. Baker Maarten Hoeben
Clemens C.W. Ruppel
Kevin M. Barry Masayuki Ikeda
Anil K. Sanwalka
Phil Belanger Donald C. Johnson
Roy Sebring
John Biddick Tal Kaitz
Tie-Jun Shan
Simon Black Ad Kamerman
Stephen J. Shellhammer
Timothy J. Blaney Mika Kasslin
Matthew B. Shoemake
Jan Boer Patrick Kinney
Thomas Siep
Ronald Brockmann Steven Knudsen
Donald I. Sloan
Wesley Brodsky Bruce P. Kraemer
Gary Spiess
John H. Cafarella David S. Landeta
Satoru Toguchi
Wen-Chiang Chen James S. Li
Ken Clements Stanley Ling Cherry Tom
Wim Diepstraten Michael D. McInnis Mike Trompower
Peter Ecclesine Gene Miller
Tom Tsoulogiannis
Richard Eckard Akira Miura
Bruce Tuch
Darwin Engwer Henri Moelard
Sarosh N. Vesuna
Greg Ennis Masaharu Mori
Ikuo Wakayama
Jeffrey J. Fischer Masahiro Morikura
Robert M. Ward, Jr.
John Fisher Richard van Nee
Mark Webster
Ian Gifford Erwin R. Noble
Leo Wilz
Motohiro Gochi Tomoki Ohsawa
Harry R. Worstell
Tim Godfrey Kazuhiro Okanoue
Lawrence W. Yonge, III
Steven D. Gray Richard H. Paine
Chris Zegelin
Jan Haagh Roger Pandanda
Jonathan M. Zweig
Karl Hannestad Victoria M. Poncini
James Zyren
Kei Hara Gregory S. Rawlins
Stanley A. Reible
The following members of the balloting committee voted on this standard:
Carl F. Andren Raj Jain Pete Rautenberg
Jack S. Andresen A. Kamerman Stanley A. Reible
Dean M. Kawaguchi
Lek Ariyavisitakul Edouard Y. Rocher
David Bagby Stuart J. Kerry Kent G. Rollins
Kevin M. Barry Patrick Kinney James W. Romlein
Daniel R. Krent
John H. Cafarella Floyd E. Ross
James T. Carlo Walter Levy Christoph Ruland
David E. Carlson Stanley Ling Anil K. Sanwalka
Linda T. Cheng Randolph S. Little Norman Schneidewind
Roger B. Marks
Thomas J. Dineen James E. Schuessler
Christos Douligeris Peter Martini Rich Seifert
Peter Ecclesine Richard McBride Matthew B. Shoemake
Richard Eckard Bennett Meyer Leo Sintonen
Philip H. Enslow David S. Millman Hitoshi Takanashi
John Fakatselis Hiroshi Miyano Mike Trompower
Jeffrey J. Fischer Warren Monroe Mark-Rene Uchida
Masahiro Morikura
Michael A. Fischer Scott A. Valcourt
Robert J. Gagliano Shimon Muller Richard Van Nee
Gautam Garai Peter A. Murphy Sarosh N. Vesuna
Alireza Ghazizahedi Paul Nikolich John Viaplana
Erwin R. Noble
Tim Godfrey Hirohisa Wakai
Patrick S. Gonia Satoshi Obara Robert M. Ward, Jr.
Steven D. Gray Robert O'Hara Mark Webster
Charles Oestereicher
Chris G. Guy Harry R. Worstell
Vic Hayes Kazuhiro Okanoue Stefan M. Wurster
Allen Heberling Roger Pandanda Oren Yuen
Chris D. Heegard Ronald C. Petersen Jonathan M. Zweig
Al Petrick
Juha T. Heiskala James Zyren
Vikram Punj
When the IEEE-SA Standards Board approved this standard on 16 September 1999, it had the following
membership:
Richard J. Holleman, Chair
Donald N. Heirman, Vice Chair
Judith Gorman, Secretary
Satish K. Aggarwal James H. Gurney Louis-François Pau
Dennis Bodson Lowell G. Johnson Ronald C. Petersen
Mark D. Bowman Robert J. Kennelly Gerald H. Peterson
James T. Carlo E. G. “Al” Kiener John B. Posey
Gary R. Engmann Joseph L. KoepÞnger* Gary S. Robinson
Harold E. Epstein L. Bruce McClung Akio Tojo
Jay Forster* Daleep C. Mohla Hans E. Weinrich
Ruben D. Garzon Robert F. Munzner Donald W. Zipse
*Member Emeritus
Also included is the following nonvoting IEEE-SA Standards Board liaison:
Robert E. Hebner
Janet Rutigliano
IEEE Standards Project Editor
vi Copyright © 2000 IEEE. All rights reserved.

Contents
3.8 Basic service set (BSS) basic rate set . 1
4. Abbreviations and acronyms. 2
7.2.3.1 Beacon frame format. 2
7.2.3.9 Probe Response frame format. 3
7.3.1.4 Capability Information field . 3
7.3.1.9 Status Code field. 5
7.3.2.2 Supported Rates element. 5
9.2 DCF. 5
9.6 Multirate support. 6
10.3.2.2 MLME_scan.confirm. 6
10.3.2.2.2 Semantics of the service primitive. 7
10.3.3.1.2 Semantics of the service primitive. 8
10.3.10 Start. 8
10.3.10.1.2 Semantics of the service primitive. 9
10.4.4 PLME_DSSSTESTMODE. 10
18. High Rate, direct sequence spread spectrum PHY specification. 11
18.1 Overview. 11
18.2 High Rate PLCP sublayer . 12
18.3 High Rate PLME. 27
18.4 High Rate PMD sublayer. 30
Annex A (normative), Protocol implementation conformance statement (PICS) proforma . 59
Annex C (normative), Formal description of MAC operation . 64
Annex D (normative), ASN.1 encoding of the MAC and PHY MIB. 88
Annex F (informative), High Rate PHY/frequency-hopping interoperability. 89
Supplement to IEEE Standard for
Information technology—
Telecommunications and information exchange
between systems—
Local and metropolitan area networks—
SpeciÞc requirements—
Part 11: Wireless LAN Medium Access
Control (MAC) and Physical Layer
(PHY) speciÞcations:
Higher-Speed Physical Layer
Extension in the 2.4 GHz Band
[This supplement is based on IEEE Std 802.11, 1999 Edition.]
EDITORIAL NOTE—The editing instructions contained in this supplement deÞne how to merge the material contained
herein into the existing base standard to form the new comprehensive standard, as created by the addition of IEEE Std
802.11b-1999.
The editing instructions are shown in bold italic. Three editing instructions are used: change, delete, and
insert. Change is used to make small corrections in existing text or tables. This editing instruction speciÞes
the location of the change and describes what is being changed either by using strikethrough (to remove old
material) or underscore (to add new material). Delete removes existing material. Insert adds new material
without disturbing the existing material. Insertions may require renumbering. If so, renumbering instructions
are given in the editing instructions. Editorial notes will not be carried over into future editions.
3.8 Basic service set (BSS) basic rate set
Change the text in this subclause as shown:
The set of data transfer rates that all the stations in a BSS will be capable of using to receive and transmit
frames to/from the wireless medium (WM). The BSS basic rate set data rates are preset for all stations in
the BSS.
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
4. Abbreviations and acronyms
Insert the following abbreviations alphabetically in the list in Clause 4:
CCK complementary code keying
HR/DSSS High Rate direct sequence spread spectrum using the Long Preamble and header
HR/DSSS/short High Rate direct sequence spread spectrum using the optional Short Preamble
and header mode
HR/DSSS/PBCC High Rate direct sequence spread spectrum using the optional packet binary con-
volutional coding mode and the Long Preamble and header
HR/DSSS/PBCC/short High Rate direct sequence spread spectrum using the optional packet binary con-
volutional coding mode and the optional Short Preamble and header
7.2.3.1 Beacon frame format
Change Notes 1 and 2 of Table 5 as shown:
Table 5—Beacon frame body
Order Information Note
1 Timestamp —
2 Beacon interval —
3 Capability Information —
4 SSID —
5 Supported Rates —
6 FH Parameter Set 1
7 DS Parameter Set 2
8 CF Parameter Set 3
9 IBSS Parameter Set 4
10 TIM 5
NOTES:
1—The FH Parameter Set information element is only present within Beacon frames generated by STAs using fre-
quency-hopping PHYs.
2—The DS Parameter Set information element is only present within Beacon frames generated by STAs using direct
sequence PHYs.
3—The CF Parameter Set information element is only present within Beacon frames generated by APs supporting
a PCF.
4—The IBSS Parameter Set information element is only present within Beacon frames generated by STAs in an IBSS.
5—The TIM information element is only present within Beacon frames generated by APs.
2 Copyright © 2000 IEEE. All rights reserved.

IEEE
HIGHER-SPEED PHYSICAL LAYER EXTENSION IN THE 2.4 GHz BAND Std 802.11b-1999
7.2.3.9 Probe Response frame format
Change Notes 1 and 2 of Table 12 as shown:
Table 12—Probe Response frame body
Order Information Note
1 Timestamp —
2 Beacon interval —
3 Capability Information —
4 SSID —
5 Supported Rates —
6 FH Parameter Set 1
7 DS Parameter Set 2
8 CF Parameter Set 3
9 IBSS Parameter Set 4
NOTES:
1—The FH Parameter Set information element is only present within Probe Response frames generated by STAs using
frequency-hopping PHYs.
2—The DS Parameter Set information element is only present within Probe Response frames generated by STAs using
direct sequence PHYs.
3—The CF Parameter Set information element is only present within Probe Response frames generated by APs support-
ing a PCF.
4—The IBSS Parameter Set information element is only present within Probe Response frames generated by STAs in
an IBSS.
7.3.1.4 Capability Information Þeld
Change the text in 7.3.1.4 and Figure 27 as shown:
The Capability Information Þeld contains a number of subÞelds that are used to indicate requested or adver-
tised capabilities.
The length of the Capability Information Þeld is 2 octets. The Capability Information Þeld consists of the
following subÞelds: ESS, IBSS, CF-Pollable, CF-Poll Request, and Privacy, Short Preamble, PBCC, and
Channel Agility. The format of the Capability Information Þeld is as illustrated in Figure 27.
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
B0 B1 B2 B3 B4 B5 B6 B7 B8 B15
Channel
CF CF-Poll Short
Reserved
ESS IBSS Pollable Privacy PBCC Agility
Request Preamble
Octets:
Figure 27—Capability Information Þxed Þeld
Insert the following text at the end of 7.3.1.4:
APs (as well as STAs in IBSSs) shall set the Short Preamble subÞeld to 1 in transmitted Beacon, Probe
Response, Association Response, and Reassociation Response management MMPDUs to indicate that the
use of the Short Preamble option, as described in 18.2.2.2, is allowed within this BSS. To indicate that the
use of the Short Preamble option is not allowed, the Short Preamble subÞeld shall be set to 0 in Beacon,
Probe Response, Association Response, and Reassociation Response management MMPDUs transmitted
within the BSS.
STAs shall set the Short Preamble subÞeld to 1 in transmitted Association Request and Reassociation
Request MMPDUs when the MIB attribute dot11ShortPreambleOptionImplemented is true. Otherwise,
STAs shall set the Short Preamble subÞeld to 0 in transmitted Association Request and Reassociation
Request MMPDUs.
APs (as well as STAs in IBSSs) shall set the PBCC subÞeld to 1 in transmitted Beacon, Probe Response,
Association Response, and Reassociation Response management MMPDUs to indicate that the use of the
PBCC Modulation option, as described in 18.4.6.6, is allowed within this BSS. To indicate that the use of the
PBCC Modulation option is not allowed, the PBCC subÞeld shall be set to 0 in Beacon, Probe Response,
Association Response, and Reassociation Response management MMPDUs transmitted within the BSS.
STAs shall set the PBCC subÞeld to 1 in transmitted Association Request and Reassociation Request
MMPDUs when the MIB attribute dot11PBCCOptionImplemented is true. Otherwise, STAs shall set the
PBCC subÞeld to 0 in transmitted Association Request and Reassociation Request MMPDUs.
Bit 7 of the Capabilities Information Þeld shall be used to indicate the usage of Channel Agility by the HR/
DSSS PHY. STAs shall set the Channel Agility bit to 1 when Channel Agility is in use, and shall set it
to 0 otherwise.
Bits 8–15 of the Capability Information Þeld are reserved.
4 Copyright © 2000 IEEE. All rights reserved.

IEEE
HIGHER-SPEED PHYSICAL LAYER EXTENSION IN THE 2.4 GHz BAND Std 802.11b-1999
7.3.1.9 Status Code Þeld
Add three Status Codes to Table 19 as shown:
Table 19—Status Codes
Status Code Meaning
19 Association denied due to
requesting station not sup-
porting the Short Pream-
ble option.
20 Association denied due to
requesting station not sup-
porting the PBCC Modula-
tion option.
21 Association denied due to
requesting station not sup-
porting the Channel Agil-
ity option.
7.3.2.2 Supported Rates element
Change the text in 7.3.2.2 as shown.
The Supported Rates element speciÞes all the values rates that this station is capable of receiving in the
Operational-Rate-Set parameter, as described in the MLME_Join.request and MLME_Start.request primi-
tives. The information Þeld is encoded as 1–8 octets, where each octet describes a single Supported Rate in
units of 500 kbit/s.
Within Beacon, Probe Response, Association Response, and Reassociation Response management frames,
each Supported Rate belonging to the BSSBasic Rate Set BSS basic rate set is encoded as an octet with the
msb (bit 7) set to 1 (e.g., a 1 Mbit/s rate belonging to the BSSBasicRateSet BSS basic rate set is encoded as
X'82'). Rates not belonging to the BSSBasicRateSet BSS basic rate set are encoded with the msb set to 0
(e.g., a 2 Mbit/s rate not belonging to the BSSBasicRateSet BSS basic rate set is encoded as X'04'). The msb
of each Supported Rate octet in other management frame types is ignored by receiving STAs.
BSSBasicRateSet The BSS basic rate set information in Beacon and Probe Response management frames is
delivered to the management entity in an STA via the BSSBasicRateSet parameter in the MLME_Scan.con-
Þrm primitive. It is used by the management entity in an STAs in order to avoid associating with a BSS if the
STA cannot receive and transmit all the data rates in the BSSBasicRateSet BSS basic rate set (see
Figure 36).
9.2 DCF
Change the eleventh paragraph in 9.2 as shown.
The medium access protocol allows for stations to support different sets of data rates. All STAs shall be able
to receive and transmit at all the data rates in the aBasicRateSet speciÞed parameter of the
MLME_Join.request and MLME_Start.request primitives and transmit at one or more of the aBasicRateSet
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
data rates. To support the proper operation of the RTS/CTS and the Virtual Carrier Sense mechanism, all
STAs shall be able to detect the RTS and CTS frames. For this reason, the RTS and CTS frames shall be
transmitted at one of the rates in the BSS basic rate set aBasicRateSet rates. (See 9.6 for a description of
multirate operation.)
9.6 Multirate support
Change the existing text as shown:
Some PHYs have multiple data transfer rate capabilities that allow implementations to perform dynamic rate
switching with the objective of improving performance. The algorithm for performing rate switching is
beyond the scope of this standard, but in order to ensure coexistence and interoperability on
multirate-capable PHYs, this standard deÞnes a set of rules that shall be followed by all STAs.
All Control frames shall be transmitted at one of the rates in the BSSBasicRateSet BSS basic rate set (see
10.3.10.1), or at one of the rates in the PHY mandatory rate set so that they will be understood by all STAs in
the BSS.
All frames with multicast and broadcast RA shall be transmitted at one of the rates included in the BSSBasi-
cRateSet BSS basic rate set, regardless of their type or subtype.
Data and/or management MPDUs with a unicast immediate address RA shall be sent on any supported data
rate selected by the rate switching mechanism (whose output is an internal MAC variable called MACCur-
rentRate, deÞned in units of 500 kbit/s, which is used for calculating the Duration/ID Þeld of each frame).
An STA shall not transmit at a rate that is known not to be supported by the destination STA, as reported in
the Supported Rates element in the management frames. For frames of type Data + CF – ACK, Data + CF –
Poll + CF – ACK, and CF – Poll + CF – ACK, the rate chosen to transmit the frame must be supported by
both the addressed recipient STA and the STA to which the ACK is intended.
In order to To allow the transmitting STA to calculate the contents of the Duration/ID Þeld, the responding
STA shall transmit its Control Response and Management Response frames (either CTS or ACK) at the
highest rate in the BSS basic rate set that is less than or equal to the rate of at the same rate as the immedi-
ately previous frame in the frame exchange sequence (as deÞned in 9.7). if this rate belongs to the PHY man-
datory rates, or else at the highest possible rate belonging to the PHY rates in the BSSBasicRateSet. In
addition, the Control Response frame shall be sent using the same PHY options as the received frame.
For the HR/DSSS PHY, the time required to transmit a frame for use in the Duration/ID Þeld is determined
using the PLME-TXTIME.request primitive and the PLME-TXTIME.conÞrm primitive, both deÞned
in 1.3.4.
10.3.2.2 MLME_scan.conÞrm
Change "set" to "sets" in the Name and Description columns for the PHY Parameter Set.
6 Copyright © 2000 IEEE. All rights reserved.

IEEE
HIGHER-SPEED PHYSICAL LAYER EXTENSION IN THE 2.4 GHz BAND Std 802.11b-1999
10.3.2.2.2 Semantics of the service primitive
Change the table as shown:
Name Type Valid range Description
BSSID MACAddress N/A The BSSID of the found
BSS.
SSID Octet string 1–32 octets The SSID of the found
BSS.
BSSType Enumeration INFRASTRUCTURE, The type of the found BSS.
INDEPENDENT
Beacon Period Integer N/A The Beacon period of the
found BSS (in TU).
DTIM Period Integer As deÞned in frame The DTIM period of the
format BSS (in beacon periods).
Timestamp Integer N/A The timestamp of the
received frame (probe
response/beacon) from the
found BSS.
Local Time Integer N/A The value of STA’s TSF
timer at the start of recep-
tion of the Þrst octet of the
timestamp Þeld of the
received frame (probe
response or beacon) from
the found BSS.
PHY Parameter Set As deÞned in frame As deÞned in frame The parameter set relevant
format format to the PHY.
CF Parameter Set As deÞned in frame As deÞned in frame The parameter set for the
format format CF periods, if found BSS
supports CF mode.
IBSS Parameter Set As deÞned in frame As deÞned in frame The parameter set for the
format format IBSS, if found BSS is an
IBSS.
Capability Information As deÞned in frame As deÞned in frame The advertised capabilities
format format of the BSS.
BSSBasicRateSet Set of intergers 1–27 inclusive (for each The set of data rates (in
integer in the set) units of 500 kb/s) that must
be supported by all STAs
that desire to join this BSS.
The STAs must be able to
receive and transmit at
each of the data rates listed
in the set.
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
10.3.3.1.2 Semantics of the service primitive
Change the table as shown:
Name Type Valid range Description
BSSDescription BSSDescription N/A The BSSDescription
of the BSS to join.
The BSSDescription
is a member of the
set of descriptions
that was returned as a
result of a MLME-
SCAN.request.
JoinFailureTimeout Integer ! 1 The time limit, in
units of beacon inter-
vals, after which the
join procedure will
be terminated.
ProbeDelay Integer N/A Delay (in µs) to be
used prior to trans-
mitting a Probe
frame during active
scanning.
OperationalRateSet Set of integers 1–127 inclusive (for The set of data rates
each integer in the (in units of 500
set) kbit/s) that the STA
desires to use for
communication
within the BSS. The
STA must be able to
receive at each of the
data rates listed in the
set. The Operational-
RateSet This set is a
superset of the BSS-
BasicRateSet BSS
basic rate set adver-
tised by the BSS.
10.3.10 Start
Change "set" to "sets" in the Name and Description columns for the PHY Parameter Set.
8 Copyright © 2000 IEEE. All rights reserved.

IEEE
HIGHER-SPEED PHYSICAL LAYER EXTENSION IN THE 2.4 GHz BAND Std 802.11b-1999
10.3.10.1.2 Semantics of the service primitive
Change the table as shown:
Name Type Valid range Description
SSID Octet string 1–32 octets The SSID of the BSS.
BSSType Enumeration INFRASTRUCTURE, The type of the BSS.
INDEPENDENT
Beacon period Integer ! 1 The Beacon period of the
BSS (in TU).
DTIM period Integer As deÞned in 7.3.12.6 The DTIM period of the
BSS (in Beacon periods).
CF Parameter Set As deÞned in Frame As deÞned in 7.3.2.5 The Parameter Set for CF
Format periods, if the BSS sup-
ports CF mode.
aCFPPeriod is modiÞed
as a side effect of the
issuance of a MLME-
START.request primitive.
PHY Parameter Set As deÞned in Frame As deÞned in 7.3.2.3 The Parameter Set rele-
Format or 7.3.2.4 vant to the PHY.
IBSS Parameter Set As deÞned in Frame As deÞned in 7.3.2.7 The Parameter Set for the
Format IBSS, if BSS is an IBSS.
ProbeDelay Integer N/A Delay (in µs) to be used
prior to transmitting a
Probe frame during active
scanning.
CapabilityInformation As deÞned in Frame As deÞned in 7.3.1.4 The capabilities to be
Format advertised for the BSS.
BSSBasicRateSet Set of integers 1–127 inclusive (for The set of data rates (in
each integer in the set) units of 500 kbit/s) that
must be supported by all
STAs that desire to join
this BSS. The STA that is
creating the BSS must be
able to receive and trans-
mit at each of the data
rates listed in the set.
OperationalRateSet Set of integers 1–127 inclusive (for The set of data rates (in
each integer in the set) units of 500 kbit/s) that
the STA desires to use for
communication within
the BSS. The STA must
be able to receive at each
of the data rates listed in
the set. The Operational-
RateSet This set is a
superset of the BSS basic
rate set BSSBasicRate-
Set advertised by the
BSS.
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
10.4.4 PLME_DSSSTESTMODE
Add switches for the new options as shown:
PLME-DSSSTESTMODE.request (
TEST_ENABLE,
TEST_MODE,
SCRAMBLE_STATE,
SPREADING_STATE,
DATA_TYPE,
DATA_RATE;
PREAMBLE_TYPE;
MODULATION_CODE_TYPE;
)
Valid
Name Type Description
range
TEST_ENABLE Boolean True, false If true, enables the PHY test mode according to the
remaining parameters.
TEST_MODE Integer 1, 2, 3 TEST_MODE selects one of three operational
modes:
— 01 = transparent receive
— 02 = continuous transmit
— 03 = 50% duty cycle
SCRAMBLE_STATE Boolean True, false If true, sets the operational state of the scrambler
to ON.
SPREADING_STATE Boolean True, false If true, selects the operational state of the chipping.
DATA_TYPE Integer 1, 2, 3 Selects one of three data patterns to be used for the
transmit portions of the tests; for example:
all one, all zeros, and random data patterns.
DATA_RATE Integer 2, 4, 11, 22 Selects:
— 02 = 1 Mbit/s
— 04 = 2 Mbit/s
— 11 = 5.5 Mbit/s
— 22 = 11 Mbit/s
PREAMBLE_TYPE Boolean null, 0, 1 Selects the preamble length.
—  0 = long
—  1 = short
Can be null.
MODULATION_CODE_TYPE Boolean null, 0, 1 Selects the modulation code:
—  0 = CCK
—  1 = PBCC
Can be null.
10 Copyright © 2000 IEEE. All rights reserved.

IEEE
HIGHER-SPEED PHYSICAL LAYER EXTENSION IN THE 2.4 GHz BAND Std 802.11b-1999
Add Clause 18 as follows:
18. High Rate, direct sequence spread spectrum PHY speciÞcation
18.1 Overview
This clause speciÞes the High Rate extension of the PHY for the Direct Sequence Spread Spectrum (DSSS)
system (Clause 15 of IEEE Std 802.11, 1999 Edition), hereinafter known as the High Rate PHY for the 2.4
GHz band designated for ISM applications.
This extension of the DSSS system builds on the data rate capabilities, as described in Clause 15 of
IEEE Std 802.11, 1999 Edition, to provide 5.5 Mbit/s and 11 Mbit/s payload data rates in addition to the 1
Mbps and 2 Mbps rates. To provide the higher rates, 8-chip complementary code keying (CCK) is employed
as the modulation scheme. The chipping rate is 11 MHz, which is the same as the DSSS system described in
Clause 15 of IEEE Std 802.11, 1999 Edition, thus providing the same occupied channel bandwidth. The
basic new capability described in this clause is called High Rate Direct Sequence Spread Spectrum (HR/
DSSS). The basic High Rate PHY uses the same PLCP preamble and header as the DSSS PHY, so both
PHYs can co-exist in the same BSS and can use the rate switching mechanism as provided.
In addition to providing higher speed extensions to the DSSS system, a number of optional features allow
the performance of the radio frequency LAN system to be improved as technology allows the implementa-
tion of these options to become cost effective.
An optional mode replacing the CCK modulation with packet binary convolutional coding (HR/DSSS/
PBCC) is provided.
Another optional mode is provided that allows data throughput at the higher rates (2, 5.5, and 11 Mbit/s) to
be signiÞcantly increased by using a shorter PLCP preamble. This mode is called HR/DSSS/short, or HR/
DSSS/PBCC/short. This Short Preamble mode can coexist with DSSS, HR/DSSS, or HR/DSSS/PBCC
under limited circumstances, such as on different channels or with appropriate CCA mechanisms.
An optional capability for Channel Agility is also provided. This option allows an implementation to over-
come some inherent difÞculty with static channel assignments (a tone jammer), without burdening all imple-
mentations with the added cost of this capability. This option can also be used to implement IEEE
802.11-compliant systems that are interoperable with both FH and DS modulations. See Annex F for more
details.
18.1.1 Scope
This clause speciÞes the PHY entity for the HR/DSSS extension and the changes that have to be made to the
base standard to accommodate the High Rate PHY.
The High Rate PHY layer consists of the following two protocol functions:
a) A PHY convergence function, which adapts the capabilities of the physical medium dependent
(PMD) system to the PHY service. This function is supported by the PHY convergence procedure
(PLCP), which deÞnes a method for mapping the MAC sublayer protocol data units (MPDU) into a
framing format suitable for sending and receiving user data and management information between
two or more STAs using the associated PMD system. The PHY exchanges PHY protocol data units
(PPDU) that contain PLCP service data units (PSDU). The MAC uses the PHY service, so each
MPDU corresponds to a PSDU that is carried in a PPDU.
IEEE
Std 802.11b-1999 SUPPLEMENT TO IEEE STANDARD FOR INFORMATION TECHNOLOGY—
b) A PMD system, whose function deÞnes the characteristics of, and method of transmitting and
receiving data through, a wireless medium between two or more STAs, each using the High Rate
PHY system.
18.1.2 High Rate PHY functions
The 2.4 GHz High Rate PHY architecture is depicted in the ISO/IEC basic reference model shown in
Figure 137. The High Rate PHY contains three functional entities: the PMD function, the PHY convergence
function, and the layer management function. Each of these functions is described in detail in 18.1.2.1,
18.1.2.2, and 18.1.2.3. For the purposes of MAC and MAC management, when Channel Agility is both
present and enabled (see 18.3.2 and Annex C), the High Rate PHY shall be interpreted to be both a High
Rate and a frequency-hopping PHY.
The High Rate PHY service shall be provided to the MAC through the PHY service primitives described in
Clause 12 of IEEE Std 802.11, 1999 Edition.
18.1.2.1 PLCP sublayer
To allow the MAC to operate with minimum dependence on the PMD sublayer, a PLCP sublayer is deÞned.
This function simpliÞes the PHY service interface to the MAC services.
18.1.2.2 PMD sublayer
The PMD sublayer provides a means and method of transmitting and receiving data through a WM between
two or more STAs, each using the High Rate system.
18.1.2.3 PHY management entity (PLME)
The PLME performs management of the local PHY functions in conjunction with the MAC
management entity.
18.1.3 Service speciÞcation method and notation
The models represented by Þgures and state diagrams are intended to
...