Đánh Giá Một Số Giao Thức Định Tuyến Đa Đường Giảm Thời Gian Trễtrong Mạng MANET

7/23/2019 nh Gi Mt S Giao Thc nh Tuyn a ng Gim Thi Gian Trtrong Mng MANET

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nh Cng vtg Tp ch KHOA HC & CNG NGH 102(02): 51 - 57

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NH GI M5T S'GIAO THC 0NH TUYDN A NGGI/M THI GIAN TRETRONG M@NG MANET

*nh Cng*, Nguy8n Anh ChuynTrng i hc Cng nghThng tin & Truyn thng H Thi Nguyn

TM TTTrong nh(ng n"m g$n y c mt hng tip c&n mi cho bi ton nh tuyn trong mngMANET l nh tuyn a ng. Bi bo ny trnh by mt cch t)ng quan vcc c im chnhtrong cchhot ng c!a mt sgiao thc nh tuyn a ng mi cho mng MANET tip c&ntheo mc tiu gim thi gian tr+, sau thc hin vic phn tch, so snh v nh gi chng theocc tiu ch vhiu n"ng hot ng, ng thi chra hng c$n ci tin c!a cc giao thc ny.Tkho:Mng MANET,nh tuyn a ng, Thi gian tr*, Tm ng, La chn ng.

GI#I THIU*Mng khng dy di ng khng cu trc(MANET) l mt mng bao gm t&p cc ntdi ng khng c c ch qun tr t&p trung.Mng MANET c khn"ng tcu hnh, tt)chc v tbo tr hot ng c!a mnh, c thtng thch vi cc mng c hnh trng ng.Tuy nhin, mi nt di ng li c nh(ng hnchvti nguyn nhn"ng lng ngun, khn"ng x l v b nh. C ch truyn thnggi(a cc nt di ng trong mng MANET l

ccha chng. Do , thi gian tn ti c!ami nt i ng trong mng l rt quan tr%ng.Vic thit k giao thc nh tuyn hiu qucho mng MANET l mt bi ton c quantm nhiu trong cc nghin cu v h thngmng di ng trong thi gian qua.

C nhiu giao thc nh tuyn n ng chomng MANET c xut v c thchiachng thnh hai nhm chnh l cc giao thctm ng trc v cc giao thc tmng theo yu c$u. Cc giao thc ny u

chsdng duy nht mt con ng ti u truyn d( liu gi(a mt cp nt ngun-ch.Thng thng y l con ng ng,n nht.Cc nghin cu trong [1], [2], [10] v [13] ch ra rng, thu&t ton tm ng ng,n nhtkhng phi l la ch%n tt nht cho mngMANET. Khi thu&t ton ny c s dng,cc nt phn b xung quanh tm s5 phitruyn lu lng d(liu nh tuyn nhiu hncc nt phn bg$n bin c!a mng. iu ny

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c thgy ra tnh trng t,c ngh5n khi c nhiukt ni c thit l&p trong mng lm nhhng ti hiu n"ng mng kha cnh thigian tr+v thng lng.

gii quyt cc hn ch ny, thay v victm ra v sdng duy nht mt con ng truyn d( liu, s5 c nhiu hn mt conng c sdng ng thi truyn d(liu trong cc giao thc nh tuyn a ng.Cc giao thc nh tuyn a ng c phnloi theo mc tiu tip c&n c!a chng. Trong

sn"m nhm giao thc nh tuyn a ng c phn loi trong [12], bi bo ny cht&p trung nh gi nhm thnht l nhm ccgiao thc nh tuyn a ng gim thi giantr+. Nhm ny bao gm cc giao thc: nhtuyn ng d phng [8], nh tuyn ang trn c s nh tuyn vng Fresnel(FZR) [7], nh tuyn AODV a ng vic ch ch%n ng theo xc sut (AODVM-PSP) [6], nh tuyn a ng c u tin(PRIMAR) [5], nh tuyn theo gc a l

(BGR) [11] v nh tuyn a ng Split-n-save [4].

Ph$n cn li c!a bi bo c t) chc nhsau: Mc 2 trnh by vhot ng chi tit, uim, nhc im v cc hn ch c!a ccgiao thc nh tuyn a ng nhm gimthi gian tr+ ni n trn. Mc 3 thchin vic so snh phn tch cc giao thc a ra trn cc tham svhiu n"ng. Mc 4phn tch cc nhc im c$n ci tin c!a cc

giao thc ny v Mc 5 l kt lu&n c!a bi bo.


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bt t,c ngh5n ti cc nt trung gian v tc thng lng tt hn ti t$ng Chuynv&n. N s dng o s chng trong qu

trnh xy dng vng. Xt mt nt ngun S vmt nt ch D trong mng. Khong cchng,n nht tnh theo schng gi(a S v D l L.Nu c mt con ng ng,n nht tS ti Dqua mt nt trung gian c L+n-1 chng th ntny thuc vo vng thn v con ng nyc g%i l con ng thn. Trong FZR, mimt nt phi duy tr mt bng khong cch.xy dng v duy tr bng ny, nt di ngsdng cc gi tin Hello. Khi mt nt nh&nc mt gi tin Hello, n s5 c&p nh&t bng

khong cch c!a mnh. Khi bng khong cchc truyn qua mng, mi nt s5 c&p nh&tbng khong cch c!a mnh v xc nh conng thnht. FZR xc nh con ng thhai theo kiu tm ng theo yu c$u. Khic mt nt nm trong vng thnht khi totin trnh tm ng bng gi tin yu c$ung, gi tin ny s5c qung b ti ccnt lng ging thuc vng thhai. Ta g%i ntthuc vng th hai nh&n gi tin yu c$ung $u tin l nt lng ging mt chng.Nt mt chng s5 tip tc qung b gi tin

ny ti cc nt lng ging c!a n. Khi mt nttip theo nm trong vng thhai nh&n cgi tin yu c$u ng tnt mt chng, n s5l nt hai chng. Nt hai chng ny s5gi gitin tr li ng cho nt ngun qua nt lngging mt chng. Nt lng ging mt chngs5 ghi li con ng chuyn tip qua nt 2chng vo bng nh tuyn c!a mnh vchuyn tip gi tin tr li ng ti ntngun. Khi nt ngun s5 ghi con ngny vo bng nh tuyn c!a mnh. Vi cch ny, mt nt ngun c th tm ra mthoc nhiu ng thhai. C thhnh thnhnhiu vng bng cch s dng phng phpny nhng hn chnhi+u, nh tuyn FZRch gii hn s dng con ng th nht vng thhai. FZR chp nh&n cch tip c&nn gin khi phn phi d( liu qua nhiung. Nu tn ti nhiu con ng khcnhau, FZR s5 phn phi d( liu tng ph$nqua tt ccc con ng. Qu trnh phn phid( liu qua nhiu ng c th iu chnhng tu6theo iu kin vb"ng thng v t,c

ngh5n c!a mng.

Giao thc nh tuyn AODV a ng v$icchch=n ng theo xc sut

Giao thc nh tuyn a ng theo yu c$udng vc t khong cch vi c ch ch%nng theo xc sut (AODVM-PSP) do tcgi Jing xut trong [6]. Giao thc ny lgiao thc m rng c!a giao thc AODVM[15]. Tin trnh tm ng c!a AODVM-DSPtng t nhAODV [9]. Qu trnh thit l&pnhiu ng tng t nh giao thcAODVM. Skhc bit chnh gi(a AODVM-DSP v AODVM l AODVM-DSP xem xtn yu ttr+d%c theo con ng khi ara mt quyt nh ch%n ng. Khi mt nt

gi mt gi tin ti ch, gi tin ny s5 chacc thng tin vthi gian b,t $u c truyni. Mt nt trung gian hoc mt nt ngun cthc lng tr+trn csthng tin ny.Nt ngun xc nh con ng tt nht theoxc sut c!a con ng trn c s tr+khi truyn theo ng ny. Xc sut c!a mtcon ng thi gi(a nt ngun S v nt ch Dk hiu l Pi(S, D) c tnh bng cng thc:

trong Ti(S, D) l thi gian tr+khi truyn tnt S ti nt D theo con ng th i v k lslng cc con ng i tnt S ti nt D.Khc vi giao thc AODVM, giao thcAODVM-PSP khng tm kim cc con ngkhc bit. N c4ng khng sdng cc gi tinnh&n bit stn ti c!a cc nt nhAODVM.V v&y, tin trnh tm ng c!a giao thcAODVM-PSP khng di+n ra thng xuynnhtrong giao thc AODVM v iu ny lmgim bt lng thng tin iu khin truyntrong mng.

Giao thc nh tuyn a ng Split-n-Save

Cc tc gi Cha v Lee hiu chnh giaothc AODVM thnh giao thc split-n-save[4] nhm t c hai mc tiu chnh: (1) m bo giao thc nh tuyn a ng hotng tt qua thi gian hot ng c!a cc ntv (2) cn bng gi(a nh tuyn v chuyntip d( liu trong mng. Cc tc gi ny

t tn cho hai mc tiu trn l khn"ng sng


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c!a mng v khn"ng p ng c!a nt. Khn"ng sng c!a mng c nh ngh3a l slng nt ang hot ng qua mt khong

thi gian cho trc. Kh n"ng p ng c!amng c nh ngh3a l t; lgi(a s lnggi tin do nt sinh ra trn slng gi tin dont chuyn tip ti cc nt khc. Cc tc gi xut mt c ch phn knh n gindnh cho vic chuyn )i lu lng gi(a cccon ng. Theo c chny, mt nt nguns5chuyn ng truyn d(liu sau khi truynk gi tin trn mt con ng. Khi k=1, giaothc s5chuyn ng truyn d(liu sau migi tin c gi. Khi k=0, n s5sdng duy

nht mt con ng cho n khi ng ny bli. Cc kt qum ph'ng trn cscc gitrk khc nhau chra rng thi gian tr+chotng gi tin cao hn khi k=0 hoc k=1 so vicc trng hp k ln hn 1. i vi trnghp k=0 hoc k=1, gi tr thi gian tr+ binng tng i rng cn i vi cc trnghp k nh&n gi tr khc, gi tr thi gian tr+bin ng khng nhiu. T cc kt qu ny,cc tc gi kt lu&n rng vi trng hpk=0 hoc k=1, mt st nt trong mng phing vai tr l nt trung tm gi(a cc kt nikhc nhau do rt d+xy ra hin tng t,cngh5n d( liu ti cc nt ny. Khi la ch%ncc gi tr k ln hn, xc xut xy ra hintng t,c ngh5n ny s5gim i.

Giao thc nh tuyn a ng c u tin

Giao thc nh tuyn a ng c u tin(PRIMAR) c xut bi Huang v Fangn"m 2005 [5]. Trong giao thc ny, nhiu conng c la ch%n gi(a nt ngun v ntch phthuc vo loi lu lng. Giao thc

ny ginh rng nt ngun nh&n bit cquan tr%ng c!a mt gi tin khi gi n tint ch. Nt ngun s dng mt gi tr phn loi cc gi tin da vo quan tr%ngc!a n. Qu trnh quyt nh ng i cto ra trn cssdng u tin c!a gi trny. Cc gi tin c u tin thp hn s5c truyn trn cc con ng di hn sovi cc gi tin c u tin cao. u tinc gn cc gi trt1 ti M vi M l utin cao nht. Gi tin c u tin cao nht

s5c truyn trn con ng ti u trong s

M con ng. ng ti u c nh ngh3al ng c tr+nh'nht. Mc d c M gitru tin c thit l&p nhng c thc trng hp slng cc con ng $u ranh'hn M. Trong trng hp ny u tincao nht c thit l&p l m = min(M, K) viK l t)ng scon ng gi(a nt ngun v ntch tm c. Sau khi nh&n c mt gitin, mt nt s5kim tra u tin c!a gi tinv chuyn tip gi ny ti chng ktip thchhp. tr+ $u-cui lun bin )i trongmng khng dy v v&y tr+ trung bnhc s dng c&p nh&t bng nh tuyn.Cc nt s5 c&p nh&t tr+ trung bnh bngcch s dng c ch bo nh&n thuc t$ngMAC. Tin trnh duy tr ng c!a giao thcPRIMAR tng tnhgiao thc DSR nhngth!tc duy tr ng c!a PRIMAR chckch hot khi c mt con ng bli hoc cmt con ng khng p ng iu kin v tr+c!a gi tin. Sthay )i ny trong tintrnh duy tr ng cho php giao thcPRIMAR p ng c yu c$u truyn d(liu c u tin cao.

Giao th

c

nh tuyn theo gc

a l

Giao thc nh tuyn theo gc a l (BGR)[11] c Popa v cc cng s gii thiunhm ci thin thng sthi gian tr+c!a hiun"ng mng bng cch sdng thng tin vst,c ngh5n trong mng. tng chnh c!agiao thc BGR l chn vo mi gi tin mtgi trgc nghing bias. Gi trny xc nhquEo c!a con ng tin vpha ch. Haithu&t ton iu khin t,c ngh5nc sdngtrong giao thc BGR l thu&t ton thu&t ton

tch gi trong mng IPS v thu&t ton tchgi $u cui EPS. Thu&t ton IPS phn tchdng lu lng truyn d( liu trnh kh'ihin tng t,c ngh5n tc thi. Hin tng nyxy ra khi c qu nhiu kt ni cng cthit l&p trn mt on mng no . trnhkh'i hin tng ny, thu&t ton IPS phn tchdng lu lng d( liu ngay trc cc imt,c ngh5n. Thu&t ton ny yu c$u thng tinvt,c ngh5n phi c nh k6trao )i gi(acc nt lng ging. Nu thu&t ton IPS khng

t c hiu qu v gim t,c ngh5n, thu&t


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ton EPS s5 c kch hot. Trong trnghp c!a thu&t ton EPS, nt ngun s5chia lulng d( liu theo nhiu con ng khcnhau v do gim c t,c ngh5n. Cc ktqu m ph'ng cho thy rng vic kt hpgi(a thu&t ton IPS v thu&t ton EPS cithin kh tt thi gian phn phi gi tin gi(acc nt v do lm cho thng lng c!amng t"ng ln.

NH GI HIU NQNG CC GIAOTH


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Cn bo gi tin tm ng: Giao thc nhtuyn a ng c th sinh ra mt s lngln cc gi tin tm ng trong mng

MANET trong tin trnh tm ng. C$n cnh(ng kE thu&t v thu&t ton hn chchuyntip cc gi tin tm ng khng c$n thitnhm lm gim hiu ng c!a cn bo gi tintm ng.

Tm ng khng hiu qu: Tin trnh tmng c!a mt giao thc nh tuyn a ngc th khng hiu qu bng cc giao thcDSR v AODV. Trong tin trnh tm ngc!a DSR v AODV, mt nt trung gian ccho php gi gi tin tr li tbnhng

c!a chng nu chng tm thy mt con ngph hp trong bnhng c!a mnh. iuny lm gim thi gian tm ng t ntngun bi v nt ngun c thkhng phi icho n khi gi tin tm ng n c ntch. Tuy nhin, trong cc giao thc nhtuyn a ng sdng cc con ng khcbit theo nt hoc khc bit theo lin kt,khng cho php cc nt trung gian gi gi tintrli tbnhng c!a mnh. Do , ntngun phi i cho n khi gi tin tm ng

ti c nt ch. V v&y, thng thng thigian tm ng c!a cc giao thc nh tuyna ng thng di hn so vi giao thcDSR hoc AODV. Do , c$n c nh(ng citin tip theo lm gim thi gian tm ngtrong giao thc nh tuyn ng d phng[8] khi sdng ng khc bit.

XGl cc gi tin p: m bo khn"ngtruyn d(liu mt cch tin c&y, cc giao thcnh tuyn a ng c!a Tsirigos [13] vWang [14] xut sdng cc ng i khcnhau gi cc bn sao c!a cng mt gi tin.Cc gi tin nhn bn chnh l cc gi tin dtha v ng nhin l chng s5 chim gi(b"ng thng c!a hthng mng. Thm vo ,cc giao thc ny c4ng yu c$u kEthu&t nhnbn gi tin ti nt ngun v l%c gi tin nhnbn ti nt ch. Cc kE thu&t x l gi tinp ny v2n c$n c ci tin t chiu qucao hn.

K-T LU/N

Trong nh(ng n"m g$n y c rt nhiu

nghin cu t&p trung vo mng khng dy

kiu khng cu trc. Mt trong nh(ng hngnghin cu quan tr%ng l thit k cc giaothc nh tuyn m bo thi gian truyn d(

liu nhanh, tin c&y cao v c c chmbo cht lng dch v. Nhm ci tin ccnhc im c!a cc giao thc nh tuyn nng truyn thng trong mng khng dykiu khng cu trc, c mt s giao thcnh tuyn a ng tip c&n theo mc tiugim thi gian tr+khi truyn d(liu c xut. Vi nh(ng ci tin a ra c!a ccgiao thc ny, hiu n"ng c!a chng cci thin so vi cc giao thc n ngtruyn thng nhng rt kh c thla ch%n

mt giao thc nh tuyn a ng gim thigian tr+l giao thc ti u i vi m%i thamsvhiu n"ng. Vic la ch%n mt giao thcnh tuyn a ng gim thi gian tr+ cnphi phthuc vo cc tham scthc!a mhnh mng c th. Ngoi ra, cc giao thcnh tuyn ny v2n c$n phi ci tin v cch tm ng, c ch la ch%n ng vcchcn bng ti c tht c hiun"ng tt hn.

TI LIU THAM KH.O[1]. Anurag K, Manjunath D, Kuri J.Communication networking: an analyticalapproach, Los Altos, CA: Morgan KaufmannPublishers; 2004. P.715-720[2]. Bertsekas D, Gallager R. Data networks, 2nded. Englewood Cliffs, NJ: Prentice-Hall; 1992p.162-170[3]. Broch J, Johnson DB, Maltz DA. Thedynamic source routing for mobile ad hocnetworks. IETF Internet-draft, draft-ietf-manet-dsr-00.txt; 1998.[4]. Cha M, Lee DK. Split-n-save multiplexing inwireless ad hoc routing. In: Proceedings of the24th annual joint conference of the IEEE computerand communications societies (INFOCOM),Miami, March 2005.[5]. Huang X, Fang Y. End-to-end delaydifferentiation by prioritized multipath routing inwireless sensor networks. In: Militarycommunications conference, MILCOM 2005, vol.2, p. 1277-1283.[6]. Jing F, Bhuvaneswaran RS, Katayama Y,Takahashi N. A multipath on-demand routing withpath selection probabilities for mobile ad hoc

networks. In: Proceedings of the international


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conference on wireless communications,networking and mobile computing, 2005, vol. 2, p.1145-1151.

[7]. Liang Y, Midkiff SF. Multipath Fresnel zonerouting for wireless ad hoc networks. In:Proceedings of the IEEE wireless communicationsand networking conference, vol. 4, March 2005,p. 19581963.[8]. Lim H, Xu K, Gerla M. TCP performanceover multipath routing in mobile ad hoc networks.In: IEEE international conference oncommunication (ICC), vol. 2, 2003, p. 10641070.[9]. Perkins CE. Ad hoc on-demand distancevector (AODV) routing. IETF Internet-draft, draft-ietf-manet-aodv-00.txt; 1997.[10]. Pham PP, Perrau S. Performance analysis of

reactive shortest path and multipath routingmechanism with load balance. In: Proceedings ofthe IEEE INFOCOM, San Francisco, California,USA, April 2003, p. 251-259.[11]. Popa L, Raiciu C, Stoica I, Rosenblum DS.Reducing congestion effects in wireless networksby multipath routing. In: Proceeding of the 14thIEEE international conference on network

protocols, Santa Barbara, California, USA,November 2006, p. 96-104.[12]. Tarique M, Kelnal E. Tepe, Sasan Adibi,

Shervin Erfani. Survey of multipath routingprotocols for mobile ad hoc networks. In: Journalof Network and Computer Applications 32, 2009,p. 1125-1143.[13]. Tsirigos A, Haas ZJ, Tabrizi SS. Multipathrouting in mobile ad hoc networks or how to routein the presence of frequent topology changes In:Proceedings of themilitary communicationsconference, vol. 2, Vienna, Virginia, October2001, p. 878883.[14]. Wang L, Jang S, Lee T-Y. Redundant sourcerouting for real-time services in ad hoc networks.In: Proceedings of IEEE international conference

on mobile ad hoc and sensor systems conference,Washington, DC, November, 2005.[15]. Ye Z, Krishnamurthy SV, Tripathi SK. Aframework for reliable routing in mobile ad hocnetworks. In: Proceedings of the 22nd annual jointconference of the IEEE computer andcommunications societies (INFOCOM), vol. 1,2003, p. 270-280.

SUMMARYEVALUATING DELAY-AWARE MULTIPATH ROUTING PROTOCOLSIN MANET

Do Dinh Cuong*, Nguyen Anh ChuyenCollege of Information Technology and Communication - TNU

Recently, multipath routing has become a new approach for routing in MANET. In this paper, weintroduces a fundamental overview about operation mechanism of several new delay-awaremultipath routing protocols. Later, we do more action in analyzing, comparing, and evaluatingthese protocols based on target and performance. Furthermore, this paper also points out futureworks that these protocols need to do.Keywords: Mobile Adhoc Network, Multipath Routing, Delay, Route Finding, Route Selecting

Ngy nhn bi:30/1/2013, ngy phn bin: 19/2/2013, ngy duyt ng:26/3/2013

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Đánh Giá Một Số Giao Thức Định Tuyến Đa Đường Giảm Thời Gian Trễtrong Mạng MANET