WPC. 2BVSZ-#|N2h=0,;&h\  PVQ&P"5t^0<<\,HH\,<,\\\\\\\\\\\44\|tDPxpdx<\<\\,\`Pd\a݅@  I.   X(# BibliogrphyBibliography݅X  (# SubheadingSubheading0\ E A.  Courier 10cpiTmsRmn 10pt (AD)TmsRmn 14pt (AD)Helv 12pt (AD)Helv 10pt (AD)Helv 14pt (AD)2f @^ "^Page `(#\CSMARadioLanRypinski,ՊX` hp x (#%'0*,.8135@8: dddy TITLE: 44` `  LIMITATIONS OF CSMA IN 44` `  802.11 RADIOLAN APPLICATIONS    l yxudddy  4 l  AUTHOR: ` ` Chandos A. Rypinski, 44` `  "Chief Technical Officer 44` ` LACE, Inc.`(#[Telephone: 707 765 9627 44` ` 921 Transport Way`-(#ZFacsimile: 707 762 5328 44` ` Petaluma, California 94954 USA   yxPdddy #\2PЖP# OVERVIEW In 802.11, there have been several contributions recommending that the Committee adopt CSMA (Carrier Sensing Multiple Access) as the keystone of the 802.11 Access Protocol. The primary motivation is seen to be the desire to truncate argument about alternatives in the interest of getting on with the Standard drafting. There is no issue concerning the importance of early completion to meet the market needs of portable computers, but there is an issue on the competence of a system using Carrier Sensing as a primary part of the access method. The reasons why the use of this method will not produce the desired result are now presented. CONCLUSION: "ACCENTUATE THE POSITIVE" What is the alternative to CSMA? The rules for a radio system are: 1)do not depend on absence of signal as a logic state. 2),do depend on presence of signal with coded information that identifies the transmitting station and system, defines the purpose of the current transmission and offers a basis to estimate how long the channel will be in use for the current and related transmissions.(# The information in 2) above has meaning to each receiving station that is involved or wants to use the channel subsequently. The necessary information for the transmit decision is not deducible from inconclusive carrier absent information. The history of practice of both the negative and positive views of these principles goes back to 1960 and before. There are many lessons that do not need learning yet again.$.@+@+:: #Xl2PdkXP#6 LIMITATIONS OF CSMA IN ă 3 802.11 RADIOLAN APPLICATIONS ă 4` hp x  "#\2PЖP#  Table of Contents `!(#o Page ă #\2PЖP# OVERVIEWZp""q1 Definition of Radio CSMAZp""q1 Basic DifferencesZp""q1 RADIO SYSTEM PROPERTIESZp""q1 Cochannel Protection RatioZp""q2 Math and TopologyZp""q2 CONSEQUENCES OF A CSMA ACCESS PROTOCOLPEERTOPEERZp""q2 CONSEQUENCES OF A CSMA ACCESS PROTOCOLCENTRAL REPEATERZp""q3 Interaction Between Separated LANsZp""q3 Duplex Efficiency LimitationsZp""q3 SIMULTANEOUS SEIZURE WINDOWZp""q3 HISTORY OF CARRIER SENSING IN MOBILE TELEPHONYZp""q4 IEEE 802.4LZp""q4 COMPARISON OF CSMA AND MESSAGEBASED ACCESS METHODZp""q4 CONCLUSION: "ACCENTUATE THE POSITIVE"Zp""q4 MOTIONSZp""q4 FIGURES: FIGURE 1 PROCEDURE FOR STATION WITH PACKET TO SENDZp""q5 FIGURE 2 MOTIONS ATTACHED TO: LIMITATIONS OF CSMA IN   802.11 RADIOLAN APPLICATIONSZp""q6 Revisions of May 2, 1991: Figures 1 and 2 added with related text on page 4