ADS-Directory Services for Mobile Ad-Hoc Networks Based on an Information Market Model

%(7(MVIGXSV] 7IVZMGIW JSV 1SFMPI %H,SG 2IX[SVOW &EWIH SR ER -RJSVQEXMSR 1EVOIX 1SHIP Christian Hutter, Matthias R. Brust, and Steffen Rothkugel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devices which might not have a ¿xed position and might join or leave the network at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prieur et de la Recherche. Any opinions, ¿ndings and conclusions or recommendations ex- pressed in this paper are those of the authors and do not necessarily reÀect the views of the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making it extremely dif¿cult for them to form common study groups. To still be able to NSMR JSVGIW XLI] QMKLX YWI ER %HLSG *SVYQ ?A 7XYHIRXW GER YWI XLI EGGSVHMRK 4(% HVMZIR ETTPMGEXMSR XS WYFQMX XLIMV UYIWXMSRW XS XLI JSVYQ ;LMPI TEWWMRK SV QIIXMRK JVMIRHW ERH JIPPS[ WXYHIRXW MRJSVQEXMSR PMOI UYIWXMSRW ERH ERW[IVW EVI I\GLERKIH F] the PDAs. The system aims at ¿nding solutions for the user’s questions or knowledge PEGOW 9WIVW EVI EFPI XS IZEPYEXI VITPMIW XS XLI UYIWXMSRW 8LI VIWYPXW SJ XLMW TVSGIHYVI are used to exclude non quali¿ed answers. +EQMRK ;LMPI XVEZIPMRK XSKIXLIV TISTPI GER YWI XLIMV QSFMPI HIZMGIW JSV QYPXMTPE]IV KEQMRK *SV I\EQTPI E 4(% QMKLX HIXIVQMRI [LIXLIV WSQIFSH] RIEVF] MW MRXIVIWXIH MR NSMRMRK E KEQI %W WSSR WSQISRI MW JSYRH XLI KEQI MRXIKVEXIW XLI RI[ HIZMGI MRXS XLI KEQMRK GSQQYRMX] %PP TEVXMGMTEXMRK 4(%W XLIVIF] JSVQ ER EHLSG RIX[SVO 8LMW WGIREVMS JSGYWIW QSWXP] SR KVSYTW SJ YWIVW PSGEXIH GSQTEVEFP] GPSWI XS IEGL SXLIV PMOI MR E XVEMR [EKSR SV FYW  %(7 %R %H,SG (MVIGXSV] 7IVZMGI %(7 MW ER ETTVSEGL JSV E JYPP] HMWXVMFYXIH HMVIGXSV] WIVZMGI JSV QSFMPI EH LSG RIX [SVOW FEWIH YTSR ER MRJSVQEXMSR QEVOIX QSHIP -X EPPS[W XLI WLEVMRK SJ TSXIRXMEPP] VITPMGEXIH MRJSVQEXMSR EQSRK ETTPMGEXMSRW VYRRMRK SR XLI RSHIW SJ E QSFMPI EHLSG RIX[SVO %(7 MW WYTTSWIH XS FI TEVX SJ E QMHHPI[EVI EZEMPEFPI SR IEGL TEVXMGMTEXMRK 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XLI MRJSVQEXMSR QEVOIX QEREKIV 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¿nally forward it. If the direction of & GLERKIW FIJSVI MX IRXIVW XLI MRJSVQEXMSR QEVOIX & XVERWJIVW XLI HEXE XS E HMJJIVIRX HIZMGI LIEHMRK XS[EVHW XLI QEVOIX % WTIGMEP GEWI SGGYVW MJ XLI -11 PIEZIW XLI MRJSVQEXMSR QEVOIX ,S[IZIV XLI WEQI WXVEXIK] YWIH F] EGXMZI HIZMGIW [LIR PIEZMRK XLI QEVOIX MW ETTPMIH (YI XS VEGI GSRHM XMSRW E RI[ -11 QMKLX LEZI FIIR GVIEXIH MR FIX[IIR -R XLEX GEWI XLI SPH -11 [MPP HIEGXMZEXI MXWIPJ 8S MRGVIEWI XLI TVSFEFMPMX] SJ XLI -11 WXE]MRK MRWMHI XLI QEVOIX MX XVMIW XS VIWMHI MR MXW GIRXIV -J RIIHIH XLI VSPI SJ XLI -11 MW XEOIR SZIV F] E HMJJIVIRX HIZMGI *MK  >SSQ XS XLI MRJSVQEXMSR QEVOIX WLS[MRK QSZMRK EGXMZI ERH TEWWMZI HIZMGIW ERH ER -11 'SQQYRMGEXMSR [MXLMR ER -RJSVQEXMSR 1EVOIX -RJSVQEXMSR QEVOIXW HMJJIV JVSQ XLI VIWX SJ XLI EHLSG RIX[SVO (YI XS XLI LMKL EQSYRX SJ EZEMPEFPI HIZMGIW [MXLMR E PMQMXIH KISKVETLMG EVIE MX MW TSWWMFPI XS IWXEFPMWL E JEWX GSQQYRMGEXMSR ERH MRJSVQEXMSR HMWXVM FYXMSR FIX[IIR XLI TEVXMGMTEXMRK HIZMGIW )ZIR MJ XLI] EVI RSX MR HMVIGX GSQQYRMGEXMSR range it is possible to use other nodes to forward messages using Àooding techniques in XLMW PMQMXIH EVIE 1IWWEKIW WIRX XS XLI -11 SRP] RIIH XS FI JSV[EVHIH XS XLI GIRXIV SJ XLI QEVOIX EW XLI -11 MW WYTTSWIH XS WXE] MR XLMW EVIE (MWEWXIV 6IGSZIV] JSV %GXMZI4EWWMZI 1EVOIX (IZMGIW (MWEWXIV VIGSZIV] RIIHW XS FI HSRI [LIR E HIZMGIW PIEZIW E QEVOIX [MXLSYX FIMRK EFPI XS TIVJSVQ XLI RSVQEP tPIEZI QEVOIXt EGXMSRW QIRXMSRIH EFSZI 8LMW GER LETTIR EW E VIWYPX SJ E TS[IVHS[R SV LEVH[EVI VIWTIGXMZIP] WSJX[EVI IVVSV -R XLI GEWI XLI HIZMGI [EW TEWWMZI XS XLI QEVOIX RS MRJSVQEXMSR MW PSWX -R XLI GEWI SJ ER EGXMZI HIZMGI EPP MRJSVQEXMSR XLEX MW RSX VITPMGEXIH MW EPWS PSWX 8LI -11 GER EP[E]W XV] XS VIWXSVI VITPMGEXIH MRJSVQEXMSR SJ HIZMGIW [LMGL are able of sending a ¿nal sign off message before shutting down. If a device can not WIRH XLMW QIWWEKI MX [MPP HITIRH SR XLI WXVEXIK] GLSWIR MJ XLI HIKVII SJ VITPMGEXMSR GER FI VIIWXEFPMWLIH GJ EPWS XLI TEVEKVETL HIWGVMFMRK MRJSVQEXMSR VITPMGEXMSR FIPS[  (MWEWXIV 6IGSZIV] JSV XLI -11 8LI PSWW SJ XLI -11 [MPP FI HIXIGXIH [LIR MRJSV QEXMSR [MPP FI EHHIH XS XLI W]WXIQ SV E RI[ HIZMGI IRXIVW XLI MRJSVQEXMSR QEVOIX %X XLEX XMQI E RI[ MRWXERGI SJ XLI -11 [MPP FI GVIEXIH (YVMRK MRMXMEPM^EXMSR SJ XLI RI[ -11 MX EWOW EPP EGXMZI SV TEWWMZI QEVOIX HIZMGIW EFSYX XLIMV JVII GETEGMXMIW -R GEWI WIZ IVEP -11W EVI GVIEXIH PIEHIV IPIGXMSR XIGLRMUYIW EVI YWIH XS IPIGX SRI SJ XLIQ 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best ¿tting in terms of types of information already managed by a market or by distance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at the suggested value, differing in the bandwidth usage. The ¿rst strategy requires HIZMGIW XS FI EFPI XS WIRH E WLSVX WMKRSJJ QIWWEKI [LIR PIEZMRK E QEVOIX ;LIR XLI -11 VIGIMZIW WYGL E QIWWEKI JVSQ HIZMGIW LSWXMRK VITPMGEXIH MRJSVQEXMSR MX WXEVXW E VIGSZIV] STIVEXMSR MI MX KIXW ERH EWWMKRW E RI[ GST] SJ XLI MRJSVQEXMSR XS ERSXLIV HIZMGI -J E HIZMGI MW RS PSRKIV EZEMPEFPI ERH [EW RSX EFPI XS WIRH E WMKRSJJ QIWWEKI SRI GST] [MPP FI PSWX 8S TVIZIRX XLMW MR XLI WIGSRH WXVEXIK] XLI -11 TIVMSHMGEPP] GLIGOW MJ EPP HIZMGIW MRZSPZIH MRXS E VITPMGEXMSR TVSGIWW EVI WXMPP EZEMPEFPI -J RIGIWWEV] XLI EJSVIQIRXMSRIH VIGSZIV] STIVEXMSR MW XVMKKIVIH  6IPEXIH ;SVO 8LIVI EVI E RYQFIV SJ [IPP ORS[R HMVIGXSV] WIVZMGIW JSV XVEHMXMSREP RIX[SVOW IRZMVSR QIRXW PMOI 3TIR0(%4 ERH 1MGVSWSJXW %GXMZI (MVIGXSV] &YX HYI XS XLI ZIV] H]REQMG WXVYGXYVI SJ QSFMPI EH LSG IRZMVSRQIRXW XSKIXLIV [MXL XLI VIWXVMGXMSRW MR XIVQW SJ TVS GIWWMRK TS[IV ERH WXSVEKI GETEFMPMXMIW XLSWI EVI RSX WYMXEFPI HMVIGXP] %(7 MW I\TPMGMXP] HIWMKRIH JSV YWI MR WYGL IRZMVSRQIRXW 8LI ETTPMGEXMSR WGIREVMSW MRXVSHYGIH VIUYMVI MRJSVQEXMSR XS FI WXSVIH JSV JYVXLIV YWEKI % [MHI ZEVMIX] SJ HMJJIVIRX ETTPMGEXMSRHITIRHIRX MRJSVQEXMSR X]TIW RIIHW XS FI managed. Simple strategies like Àooding the network by disseminating data using adap- XMZI TVSXSGSPW PMOI MRXVSHYGIH MR ?A EVI RSX VIEWSREFPI MR KIRIVEP % HMJJIVIRX ETTVSEGL MW YWIH MR 231 ?A [LMGL JSV[EVHW UYIVMIW ERH GVIEXIW VIWTSRWIW JVSQ IZIV] RSHI MR XLI RIX[SVO -R FSXL WXVEXIKMIW FVSEHGEWX WXSVQW EVI PMOIP] XS SGGYV 7-() 7YVJIV ?A MR XYVR SRP] EPPS[W XLI EYXSQEXMG I\GLERKI FIX[IIR HMVIGXP] GSRRIGXIH HIZMGIW FEWIH SR user pro¿les, giving the applications access to a limited set of information only. ADS EPPS[W ETTPMGEXMSRW XS YWI XLI W]RGLVSRSYW PSGEP UYIVMIW XS EGGIWW WYGL MRJSVQEXMSR ERH EHHMXMSREPP] TVSZMHIW EW]RGLVSRSYW WQEVX VIQSXI UYIVMIW JSV VIXVMIZMRK HEXE JVSQ MRJSVQEXMSR TSSPW GYVVIRXP] EZEMPEFPI SR MRJSVQEXMSR QEVOIXW &SXL 838% t8YTPIW SR XLI EMVt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  +SIVKIR ( *VI] , 0ILRIVX ./ 7XYVQ 4 1EVOIXTPEGIW EW 'SQQYRMGEXMSR 4EXXIVRW MR 1SFMPI %H,SG 2IX[SVOW 4VSGIIHMRKW SJ /M:7  /SQQYRMOEXMSR MR :IVXIMPXIR 7]WXI QIR   &VYWX 1 6SXLOYKIP 7 'SSTIVEXMZI ERH 1SFMPI 0IEVRMRK MR %H,SG 2IX[SVOW 4VSGIIHMRKW SJ ;')8)  ;SVPH 'SRJIVIRGI SR )RKMRIIVMRK ERH 8IGLRSPSK] )HYGEXMSR &VEWMP   /YPMO . 6EFMRIV ;&EPEOVMWLRER , %HETXMZI 4VSXSGSPW JSV -RJSVQEXMSR (MWWIQMREXMSR MR ;MVIPIWW 7IRWSV 2IX[SVOW 4VSGIIHMRKW SJ XLI XL %'1-))) 1SFMGSQ 'SRJIVIRGI 7IEXXPI ;% %YKYWX   (SZEP (31ELSR] ( 2SQ 6IWSYVGI 0SGEXMSR ERH (MWGSZIV] JSV %H ,SG 1SFMPI 2IX [SVOW 4VSGIIHMRKW SJ XLI WX %RRYEP 1IHMXIVVERIER %H ,SG 2IX[SVOMRK ;SVOWLST 1IH LSG2IX   8SY^IX ( 1IREYH .1 ;IMW * 'SYHIVG 4 &ERXVI 1 7-() 7YVJIV % 7TSRXERISYW -RJSVQEXMSR (MWGSZIV] ERH )\GLERKI 7]WXIQ 4VSGIIHMRKW SJ XLI RH -RXIVREXMSREP ;SVOWLST SR 9FMUYMXSYW 'SQTYXMRK ERH 'SQQYRMGEXMSR &EVGIPSRE 7TEMR   1EQIM 1 >EQFSRIPPM * 0ISTEVHM 0 8YTPIW SR XLI %MV % 1MHHPI[EVI JSV 'SRXI\X%[EVI 4IVZEWMZI 'SQTYXMRK 8IGLRMGEP 6ITSVX 2S (-71- 9RMZIVWMX] SJ 1SHIRE ERH 6IK KMS )QMPME -XEP] %YKYWX   ,IVVQERR / 1)7,1HP  % 1MHHPI[EVI JSV 7IPJ3VKERM^EXMSR MR %H LSG 2IX[SVOW 4VS GIIHMRKW SJ XLI WX -RXIVREXMSREP ;SVOWLST SR 1SFMPI (MWXVMFYXIH 'SQTYXMRK 1('  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