Nghiên cứu một số vấn đề tấn công lớp mạng của mạng tùy biến không dây.PDF

Nhtrqc diem:do router phai xir ly nhieu, nen chiem nhieu b0 nha, t6c dO CPU cham hcm nen tang dO tre.Viec sir dung cac giao thirc djnh tuyen truyen thOng trong mang MANET se din den rat

Phan Trung Nghia

A08348 CHU'ONG I TONG QUAN YE MANG MANET

1.1 Gifri thieu

Cac thiet bi di dOng nhu cac may tinh xach tay, vbi dac tnmg la cong suit CPU, b0 nh6 km, dung lin;mg dia hang tram gigabyte, !chi nang am thanh da phucmg tier' va man hinh man da tr6 nen phO bien trong dbi song hang ngay va trong cong viec Ding thin, cac yeu cau ket nOi mang de sir dung cac thiet hi di dOng gia tang din ke, bao gOm viec hi trq cac sari phim mong v8 tuyen dtra tat v8 tuyen hoac hOng ngoai ngay can nhieu Vei kieu thiet bi dien toan di dOng nay, thi gift nhang ngubi sir dung di dung luon mong muOn c6 su chia se thong tin

Met mang thy bien la met tOp hqp cac thiet hi di dOng hinh thanh nen met mang tom thin ma {thong can str trq &Op cua bit kj, sr quart 15, top trung hoac cac dich vu ho trq chuan nao dun:mg co ten mpg dien rOng ma a d6 cac thiet bi di dOng co the ket not duqc Cac node duqc to do di chuyen va thiet 10p no thy Sr Do

do, topo mang khong day co the thay dOi met each nhanh chong va !thong the du bao

Hinh 1.1: M6 hinh mot mgng MANET

1.2 Ljch sir

Nguyen 1Y lam viec caa mang Adhoc bit nguOn tir nrun 1968 khi ck mang ALOHA ductc thvc hien Tuy the tram lam viec la c6 djnh nhtmg giao thirc

ALOHA da thvc hien viec quern ly truy cap kenh truyen dm% dang phan tan, day la

co sir ly thuyet de phit trien ky thuot truy cop kenh phan tan vao mang Adhoc

Nam 1973 to chirc DARPA di bit du lam viec tren mang vo tuyen g6i tin PRnet Day la mang vo tuyen g6i tin da chang dAu tien Trong d6 cic node kip tic veri nhau de girl dU lieu ten mOt node nim a xa khu vvc ket not th6ng qua mOt node khic N6 cung cap co the cho viec quern ly hoat Ong tren co sir tap trung va phan tan

MOt lqi diem dm lam viec da chang so yeti don ching la triAn Thai da chang tho thuon lqi cho viec dung lai tai nguyen kenh truyen ve ca khong gian, thin gian va giam ning Itging phit can thiet

Sau d6 co nhieu mang v6 tuyen ea tin phat trim nhtmg cic hg thOng khong day nay van chin bao gia tai thy ngtrai dung cho den khi chuan 802.11 ra IEEE di dOi ten mang vo tuyen gin tin thanh mang Adhoc

1.3 irng dyng

Quilt; Hogt dOng phi tap trung ciut mpg Adhoc va khong phi thuOc vio co

so ha tang mang la mOt yeu to thiet yeu doi yeti vvc quern sv, nhat la trong the tithing hqp chien kh6c lief, citc co se ha tang mang bj phi hity Lk nay mang Adhoc la Iva chqn s6 mOt de cac thiet bj truyen thong lien lac yen nhau *it each nhanh chimg

Truying hpc: Chung ta cling co the thiet lap cic mang Adhoc trong true:mg hoc, lop hoc, thu vien, san truing, de ket not the thiet bj di dOng (laptop, smartphone) lai yeti nhau, giup sinh vien, they co giio c6 the trao dal bai mOt each nhanh cheong thong qua mang adhoc vira tho

Gia clink: Tai nha ban co the tao nhanh mang Adhoc de ket nil the thiet bj di

dOng dm ban yeti nhau, nher d6 ta co the di chuyen ttr do ma van dam him kat not truyen taidfr

Kit net ccic thiit bj din ni vbi nhau: Trong nhltng nam ten khi ma cic thiet bj

din tir deu duqc gin clic giao tiep khong day, glop chting c6 the trao d6i giao tiap

Phan Trung Nghia

A08348 voi nhau thi mpg Adhoc se rat phu hqp de tp nen mOt he th6ng thong mirth co kha flan lien ket yeti nhau

1.4 Clic d$c dam ctia mang MANET

Thiet bj t r tri dau cu & (Autonomous terminal): trong MANET, mOi thiet bj di

dOng diu cuOi la mOt node tv tri NO c6 the mang chirc niing cita host va router Ben canh kha rang xir 15, cc ban ctia mOt host, et node di Ong nay c6 the chuyen d6i chfre nang nhu met router Vi vOy thiet bj du emit va chuyen mach la khong the phan biet ductc trong mpg MANET

Hoot &Ong phan tan (Distributed operation): vi khong c6 he then mpg ha tang cho ten tam kiem soat hot dung dui mpg nen vied kiem soat va quan ly ho#t dOng ciut mang duqc chia cho cac thiet bi dau cuOi Cac node trong MANET doi h6i phai c6 sv cong tic yeti nhau Khi can thiet cac node hog Ong nhu mtjt relay de thvc hien chat 'tang cita minh Vi dv nhu djnh tuyen va bio mitt

Dinh tuyen da chtemg (Muftihop):thusia town di/1h tuyen kh6ng day co ban co the (filth tuyen mOt chong va nhieu ch(ing dva vio the thuOc firth lien ket khac nhau va giao thlic djnh tuyen Singlehop MANET den gian hen multihop a van de cAu true VI thvc hien vei chi phi thip hen, it ling dung Khi truyen cac gei dfr lieu tir nguOn den dich trong phiun vi truyen tai true tiep kh8ng day, cac goi du lieu se

ductc chuyen tiep qua mOt hok nhieu nut trung gian

Topo wing dOng (Dynamic network topology): vi cac node la di dOng nen au true mpg eel the thay &it nhanh va kh8ng biet twee, cac ket not giara cac thiet bi c6 the thay del theo th&i gian MANET se thich img tuyen va dieu kien Ian truyen giOng nhu nniu di dOng va the node mpg di dOng Cie node trong mang thiet lop

djnh tuyen dung v6i nhau khi chimg di chuyen, hinh thanh mang rieng dui cheng Han nita mOt nguari dfing trong MANET co the khong chi hog gong trong mang ken di dOng d#c biet, ma con c6 the yeu au truy cep vio mpg cong cong nhu Internet

Giao dOng ve dung lutmg lien kit (Fluctuating link capacity): ban chat ti le Mt bit cao dui ket not khong day an quan tarn trong mpg MANET Ket not tir dau emit nay den du cuOi kia co the duqc this se qua mot vai ch#ng Keith giao tit? a

dau cuOi chju inh hoeing dm nhieu, hieu img da dubng, sg giao thoa, va bang th8ng clut no it hon so vol mpg co day Trong mot vai tinh hueing, truy cep cua

hai nguai dung co the qua nhieu lien ket khong day vi the lien ket nay co the khong dOng nhAt

rdi uu hoa cho thiet bf dint mai (light-weight terminals):trong hAu het cac twang hgp cac node mpg MANET la thiet bi dau cu6i vat toe de xir 15, curt CPU thip, b0 nhe it va ltru ter dien nang it Vi v3y an phai tOi tru hem cac thuet man va

car che

1.5 Kieu kit ntii va chi (10 host dOng

1.5.1 Cic kieu ket not topo mpog

a) Along may cha di Ong

CS topo nay cac thiet bi chi lien ket voi met may chit duy that, cac thiet bi lien kat yen may chit

W. - tan mit% aware au Maps

Hinh 1.2: Mang may chn di tong

Phan Trung Nghia

A08348

b) Mgng c6 cac thiit tn di Jong khong clang nhiit

topo nay cac may co the lien ket trip tiep yeti nhau trong pham vi phi song

cua minh

S

Hinh 1.3: Mgng cac that obi di Ong khong dung nhiit

1.5.2 Che dq hoat Ong

a) Chi dO IEEE-Adhoc

the do nay the node di Ong truyen thong true tiep yea nhau ma kh8ng an

co so tang, cac lien ket !thong thuc hien qua nhieu cheng

Hinh 1.4: Chi dO IEEE-Adhoc

b) Chi do co so ha king

Che do nay mpg bao gom the diem truy cep AP c6 djnh va cac node di dOng tham gia vao mang, dive hien truyen thong qua the diem truy cep Cac lien kit có the thwc hien qua nhieu chAng v the dO My

Binh 1.5: Chi do hg tang

1.6 Phan loni MANET

1.6.1 Theo giao thin

a) Single-hop

Mpg MANET djnh tuyen Singel-hop 11 logi mpg adhoc don gifin nhAt Trong

do, tat ca cac node deu nim trong tang met yang pith song, nghin la the node co the ket not nye tiep yeti nhau ma kung can node Ming gian.Ctic node có the di chuyen ty do nhtmg chi trong phqm vi nhAt djnh du de the node lien ket trkrc tiep yeti cac node khic trong mang

Phan Trung Nghia

A08348

Hinh 1.6: Giao thee don bribe b) Multi-hop

Day la me hit ph6 Bien nhat trong mpg MANET, no khic vai mo hinh trate

la cac node co the ket not vm cac node Mt trong mang ma co the 'thong can ket

not tnrc tiep sten nhau Cie node c6 the djnh tuyen yen cac node khfic thong qua cac node trung gian trong mang De mo hinh nay host dOng mot each hoin him thi

can phai c6 giao thfrc djnh tuyen phu hop vei mo hinh mpg MANET

Hinh 1.7: Giao thee da bribe

c) Mobile Multihop

Me hinh nay cling tuang nr vei mo hinh multi-hop nhung sv khfic biet a day la

mo hinh nay tap trung vao the ling ding co tinh chat thin gian thvc: audio, video

1.6.2 Theo chile ning

a) Mgng MANET cldng cap (Flat)

Trong kien true nay tit ca the node co vai fro ngang hang yen nhau (peer to peer) va cac node d6ng vai tr6 nhu cac router dinh tuyen de lieu g6i tren mpg Trong nhOmg mpg Ion thi eau true Flat Wang to:Si uu hea viec se ding tai nguyen bring thong dm mpg vi rilang tin dieu khien phai truyen tren toitn be mpg N6 thich hqp yen nhemg topo co the node di chuyen nhieu

b) Mgng MANET pluin cap (Hierarchical)

Day la mo hinh sir dgng phi) bien 'that Trong mo hinh nay thi mang chia thimh cac domain, trong mei domain bao gem met ho4c nhieu cluster mei cluster Chia thanh nhieu node CO hai logi node lit master node va normal node

Master node 11 node quitn trj co nhiem vu truyen du lieu dm the node trong ding cluster den cac node trong cluster khic va ngugc Igi, not each khic no nhu met gateway

Normal node la cac node nam trong cling met cluster NO co the kat nOi yeti cac node trong cluster hoac ket Wri cluster lchfic thong qua Master node

Vei cac co the tren, mpg sir dung tai nguyen bang thong hieu qui bon vi cac tin Stan chi phai truyen trong met cluster Tuy nhien vier quan 15, firth chuyen deng cua cac node tre n'en phirc tap hon Kien true m(mg phan cap thich hqp cho cac mang co firth chuyen deng thip

Phan Trung Nghia

Hinh 1.9: Mang MANET kit hqp

1.7 Wet lu#n

Chuang nay cung cap nhOng kien thic tong quan ye ming thy bien adhoc not chung vi ming MANET not rieng, tir cac doe diem, cite kieu ket not Ara the dO hog clOng, phan !oil dira UM' mOt set giao thfrc vi chire nitng lam ca so cho cac nOi dung trong chuang sau

CHIJONG II DJNHTUYEN VA CAC DE DQA BAO MAT

TRONG MANET

2.1 Viin de djnh tuyen trong mting MANET

2.1.1 Cac think toin djnh tuyen truyen thOng

Cie giao thus djnh tuyen truyen thing sir ding hai giiti thuot:

• Distance Vector: RIP, IGRP,

Nguyen tic hog dOng: mr3i router se giri bang djnh tuyen cis minh cho tat

ca cac router dirge not trite tiep veri no Cie router de so sanh yeti bang djnh tuyen ma minh hien co va Iciem tra Iai cac tuyen duemg dm mirth veti cac tuyen duang meri diem dirge, tuyen duong nao tei tm han se dirge dim vao bang djnh tuyen Cie goi tin cap nhit se dirge giri theo djnh IcS , (30 gitly yeti RIP ,90 giay cleti yeti IGRP)

UV diem: a ciu hinh, router khong phiti xir 15, nhieu nen khong Mn nhieu dung lircmg130 nher WI CPU co hie do xit ly nhanh han

Nhugc diem: he thong metric qua don glen (nhu Rip chi la hop-count ) din den vier cac tuyen dtrimg dirge chgn vao bang dinh tuyen chtra phai tuyen duang tot nhit.Vi cac gig tin cep nhit dirge girl theo dinh 16 , nen met lugng Wing th8ng ding ke se IA chiem Do router hOi tit chum, din den vise sai lech trong bang din!' tuyen gay nen hien tugng yang lOp (loop)

• Link State: OSPF, IS-IS

Nguyen tic hoot dOng: cac router khong gin bang djnh tuyen ciut minh, ma chi giri tinh trong ctia cac dyeing lien ket trong ca sir dir lieu trong thii lien ket (linkstate-database) dm minh di cho eke router khac, cac router se ap dung giiti

Phan Trung Nghia

A08348 thuat SPF, to xay dung bang (firth tuyen rieng cho minh Khi mpg a hiji

At, the giao thirc Link state g kh8ng giri 4p nhat djnh IcY ma chi giri khi nao

6 su thay d6i trong mpg (1 dubng bj down , can six dung throng du phi:mg)

Uu diem: co the thich nghi duqc yeti da so hg th6ng, cho phep nguiri thiet ke co the thiet ke mang Iinh host, phial Ong nhanh v6i tinh huOng xay ra.Do khOng giri cap nhat djnh Icy nhu Distance Vector, nen Link State blo dam duce bang thong cho the duCmg mang

Nhtrqc diem:do router phai xir ly nhieu, nen chiem nhieu b0 nha, t6c dO CPU cham hcm nen tang dO tre.Viec sir dung cac giao thirc djnh tuyen truyen thOng trong mang MANET se din den rat nhieu van de fro ngai can gnu quyet

✓ Tieu ten nang luqng nguen nuoi cho the cap nhap djnh IcY nhu trong

giao thirc djnh tuyen Distance Vector

✓ Tieu ton bang thong mang cho cac cap nhap dinh

✓ Lam qua tai b0 vi xir ly elm thiet bj: khi the th8ng tin cap nhat, so

node mpg tang len

✓ To ra nhieu dtrang di du thira

2.1.2 Cu yeu cau chinh dig vai viec djnb twin trong mung MANET

Cac giao thirc djnh tuyen trong mang MANET an dam bao:

• Thich ang nhanh khi topo »King thay khi the node mang di chuyen nhanh, yeu cau ket n6i tang len thi the giao thirc host diang theo ca cha t tiep can top trong se giam hieu qua r6 rut do phai Mn nhieu thei gian de thu thop

thong tin ye trang thin hien tai va phat tan Iii n6 Trong khi do cAu hinh

mang co the di thay d6i khac di risi

• Dam bao hieu qucitrong mai trufmg truyen khi cac node clang yen: lac nay

topo mpg IA c6 djnh kh6ng thay d6i nen the giao thirc djnh tuytm chi can giri cac cap nhat khi co yeu cliu hoik mang thay dOi nhu viec miat node nao

de tit ket nei

• Khong có lap dinh can ngan chan hien tucmg nay, bai vi khi do the goi tin bj djnh tuyen sai, din den viec hi truyen quay wing lien tuc trong

mot so ket nal mang, kb& cho bang thong mang va cac tai nguyen !chic nhu nthg Krung nguan nu8i bj tieu tan vet ich

• Bdo men: viec djnh tuyen trong mpg MANET co nguy ca bj tan ding a

ding bang cac phuang phap nhu xam nh(ip dubng truyen, phitt lai, thay dai cac gai tin tieu de, dieu hut:mg the thong diep djnh tuyen Do do khi thiet ke cac giao that djnh tuyen can phai co phtumg phip phit hien dirge vi ngan than cac lo3i ten cong

2.1.3 Plan lospi the kg Mutt djnh tuyen

a) Link state vin Distance vector

Thucit tocin djnh twin vector khocing cach(distance-vector routing protocols)

Thujt total nay dung thuat tom Bellman-Ford, trong do chi djnh mot con se, gqi la chi phi (hay trung s6), cho mai mot lien ket gith cac node trong mang Cac node se girl thong tin ve dubng di tir diem A den diem

B qua the duang truyen (ket n6i) mang Iii tang chi phi thip nhit (la tang cac chi phi ctia cac ket nai gift the node dirge dung)

Thuat tofu' hoot don veri nheng himh dthg rat dun gem Khi mot node lcheri dOng Ian du, no chi biet the node ke Uwe tiep yeti no, vi chi phi true tiep de di den do (thong tin gam: dank sach cue the dich, tong chi phi den tang dich va buck ke tiep de girt de lieu den do to nen bang djnh tuyen, hay bang khoing each) Mai node, trong mot tien trinh, girl den tirng "hang xem" ding chi phi dm no de di den cac dich ma no biet Cac nodehang x6m phan tich thong tin My, va so sanh veri nhemg thong tin ma chimg dang "biet"; bat IcY dieu gi cal thin doge nhang thong tin cluingdang co se dirge due vao cac bang djnh tuyen cue nhimg hang xem nay Den khi ket dine, tat ca node tren mpg se tim ra buerc truyen

ke tiep nit tru den tat ca mui dich, va tong chi phi tin nhat

Khi mot trong the node gap van de, Meng node !chic co sir dung node hong nay trong 10 trinh cita mink se loci be nheng 10 trinh de, va to nen thong tin men dm bang djnh tuyen Sau do cluing chuyen thong tin nay den tat ca nut gait ke va lap lid qui frith tren Cu& ding, tat ca node tren

Phan Trung Nghia

A08348 mang !thin duqc thong tin cop Mit, va sau do se tim throng di m&i den tit ca cac dich ma thong con toi duce

tocin clinh tuyin trong thcii kit ndaink-state routing protocols)

Khi ap dung cac thu3t town trang thai ket noi , mOi node sir dung dia lieu

ca sot ciut no nhu la mOt ban dO cim mpg yeti Bang melt do thi De lam dieu nay, mOi node phat di tai toim mpg nhimg th8ng tin ve cac node khac ma n6 c6 the ket noi duqc, va tirng node g6p thong tin mOt each doc lip vio bitn di) Sir dung ban a nay, mOi node sau do se xac djnh duqc tuyen duang tot nhit tir no den mqi nut khac

Thuit town di lam theo each nay la Dijkstra, bing each xay dung eau true du lieu khac, clang cay, trong d6 nodehien tai la gee, va chira mqi node khitc trong mang Bit du veri min cay ban Mu chi chira chinh no Sau do Ian Itrqt tir tip cac node chua dirge them vlo cay, no se them node co chi phi thip nhit den met node di co tren cay Tiep tuc qui trinh den khi mqi node deu duqc them vito cay

City nay sau d6 plum At de xay dung bang djnh tuyen, dua ra buck truyen ke tiep tot tru, de tir met node den bit kj , node khic tren mang

So sank cac thudt town dinh tuyin

Cfic giao thirc djnh tuyen theo thuit tom vector khofing each don glen

va hieu qua han trong cite mang nh6, doi hoi it (neu co) sir giam sat Tuy nhien nhuqc diem dm no la kha ring hei to chim khi mang Ian va thay doi, dieu nay clan den sir phit trien cua cac thujt toan trang thai ket noi tuy phirc tap han nhung Mt han de dung trong cac mang len

U'u diem chinh cua djnh tuyen bing trang thai ket nOi la phan img nhanh nhay han, va trong met Ichofing thin gian co han, di yeti sir thay din ket Ngoai ra, nhung &Si doge giri qua mang trong djnh tuyen bing trang thai ket nOi thi nho han nhang g6i dung trong djnh tuyen bang vector Dinh tuyen bang vector doi hei bang djnh tuyen diy do phai dirge truyen di, trong khi djnh tuyen bang trang thai kat mil thi chi co

thong tin ve hang x6m cita node duqc truyen di Vi v(iy, cic gal nay dimg tai nguyen mango mirc kh8ng ding ke Khuyet diem chinh ciut djnh tuyen bang trong thai ket noi la no doi hoi nhieu sv luu frit va tinh toin de chay han dinh tuyen bang vector

b) Dinh tuyin phan zing va din!r twin cha ring

Cic giao thirc djnh tuyen trong mpg MANET duqc phan chia thank the loii: djnh tuyen chit ling (proactive), dinh tuyen phin img (reactive) va djnh tuyen lai ghep gifts hai logi att Cic giao thac djnh tuyen chit ling sir dung phuang phip phit tin (floading) de quing bi thong tin toi ck thiet bj Phuang phip nay cho phep thai gian thiet lap &rang nhanh dra tret' the tham so girl tea thiet bj sin sang cho ket noi Tuy nhien, phuang phip nay cling lam luu luvrng cic g6i tin tim duang tang len rat len, day chinh 11 nhtrqc diem clia phuang phap nay Giao thirc djnh tuyen hung thai lien ket toi tru OLSR va giao thirc djnh tuyen vector khofing each tan ty dich DSDV la hai vi du cilia giao thirc dinh tuyen chit (mg

Ck giao thirc djnh tuyen phim img thiet lop tuyen dip theo tang y'eu cau ket noi Phucmg phip nay han the duqc chi phi tim duang, nhtmg nhtrqc diem

ca ban la gay tre Ion cho cic khung truyen din dau tien cling Mut thai gian

*al &rang din ch(im Hai giao thirc phin ting dien hinh la giao thirc dinh tuyen vector khoing each theo you eau AODV vi giao thirc djnh tuyen nguOn dOng DSR

MOt khi xiy ra lei tai node, the giao thirc djnh tuyen thuang khoi phuc

&rang den bang phuang phip thiet lop tuyen moi HAu het cac tiep can hien nay deu sir dung thong tin phin hoi tai thiet bi ngulin nhim kheri tao tuyen mei,

vi v#y km ltrong bin tin trao dOi la rat 16fn vi tang len rat nhanh khi kich thuot mang 16n, nhat la dOi veri cic giao thirc djnh tuyen chit img Khi kich thuoc ming tang cling ding nghia Arai sir suy giim hieu Wing mang do hien tuving tre cos thit tyc djnh tuyen vi truyen khung diu tien hing len rat Ion neu sir dung giao thirc (firth tuyen phin img

c) Dinh tuyin ngutin va dinh tuyin theo chdfb wag

Voi djnh tuyen ngu6n, tan be, thong tin ve duang di teri dich duqc dOt

trong twang tieu de dm gai tin de lieu, cic node trung gian chi vie chuyen

Phan Tnmg Nglila

A08348 tiep gait tin theo dtrerng trong tieu de Lqi diem cria giao thire nay la lotti be) duqc nhu cau quitng ba dueng dinh ky vit the gal tin kham pha (discovery) hang x6m

Trong dinh tuyen theo chn, khi mgt node than duce g6i tin can chuyen tai dich, node do chuyen tiep gen tin theo chAng tiep theo huOng tai dich ma no hitt Node tiep theo lai chuyen tiep goi tin den dich theo nht-mg chang ma no biet dva vao bang dinh tuyen tha no Qua trinh tren se dimg lai khi gen tin duqc chuyen tai dich Nhtrqc diem ciia phtumg phip nay la tat ca cac node can duy tri thong tin dinh tuyen nen phai xir ly nhieu ham va co kha nang tao thanh cfic yang lap dinh tuyen

2.2 Cac giao that dinh tuyen chinh trong ming MANET

MANET ROUTING PROTOCOL

Hinh 2.1: Ccic giao thtic dinh tuyin trong MANET

2.2.1 Giao tharcdinh tuyenDSDV

DSDV (Destination-Sequenced Distance-Vector Routing) la giao dilly chi' (mg

dva tren dkra tren thujt torin Distance vector duqc xay dung beri C.Perkins vaP.Bhagwat nAm 1994 Giao thirc nay &gm xay dvng dva tren tieu chi giit

nguyen stir don gian ciut giiti thu3t Bellman-Ford vit loai be van de yang 1Itp

Truyn thong tin djnh tuyin: Thong tin djnh tuyen duqc girl quang be (broadcast) us tat ca the node hang xem lien ke no Thong tin cap nlf(it duqc phat dinh ky hoc ngay khi co cac thay dii xay ra trong mong De birth l#p djnh tuyen DSDV gon s6 thu to chin cho moi duting SO thin to duqc On ben node dich, duqc girl di trong g6i tin cap nh#p SO thin tv nay cho they de mei dm min dueing, duong nao co so thu tv cao ham duqc xem la tot ham

Hinh 2.2: Dinh tuyin trong DSDV

SO tht tv nay se tang len met don vi khi met nodephat hien duang di taxi dich

co lien ket bi hong khi no khong nh(in duqc cep nh#t djnh kY Khi ay trong g6i tin cop nh#t ke tiep no giri di se quang ba clueing ten dich nay co s6 ch#rtg bang ve hen (metric — co) va tang thfr tv clueing

Khi met node nh#n duqc th6ng tin mei ve met tuyen clueing, tuyen nay duce chqn neu no co so thu tkr Ion ham cac so thir tier khac eta ding tuyen de trong bang djnh tuyen Neu no co cling s6 tht tv thi no se duqc chqn neu co so metric tot ham

se-De lam giam kich thute gel tin cap nhjp, DSDV sir dung hai loM th6ng dip cop nhOt le:

Phan Tning Nghia

A08348

Full dump: cip nhit day du Thong diep nay bao gem than be thong tin dinh tuyen ma node do biet den than diem de

Incremental dump: c#p nhit boi sung G6i thong diep nay chi bao gem

cic thong tin ve nhOng thay doi tir fan cap nhit day de gin Milk Hai foci thong diep cot nhit nay thrqc Iuu vho hai bang khic nhau, mett bang de chuyen tiep cac gtii tin day du, met de phitt cac goi tin cap nhit G6i tin 4p nhit dhy de chi dirge phit thuong xuy'en khi cac node thu&ng xuyen di chuyen, khi mang it thay dei, che yeu chi co goi tin 4p nhit be sung dirge giri di

2.2.2 Giao thircdinh tuyenOLSR

OLSR (Optimized Link State Routing Protocol) lit giao thin chti frog (Iva tren

thuit tom tang thai ket not (Link state) Cic node giri dinh lcjr ra toim mang thong diep "Hello" de trao dei thong tin ve hang xem Thong tin nay bao gam IP dm node, se thr hr vi danh sach cac thong tin khoing each cue cac node hang x6m Sau khi cop nhit !Mang thong tin nay node se illy dvng len bang djnh tuyen cue

no vi c6 cal !thin ten the ve tom mpg Dva vim bang djnh tuyen nay no c6 the

tv tinh dirge dubng di teti folic node khic dva vio thu#t tofin tim duerng di ngin nhat Khi met node nhin dirge met goi tin trimg 1#p yeti ding s6 thin tit no se loci

be g6i tin My Trong bang dinh tuyen node luu tilting tin djnh tuyen teri tit ca cac node khic trong mang Meng thong tin nay chi dirge cip nhit khi:

Khi node nh#n thity sv thay doi trong quan he' hang xom (vd: mat lien ket den node hang x6m, )

Tuy'en dubng teri cac node dich khic het hen (qui lau khong dirge cip nhop)

Phfit hien ra dubng di mei ngin hen de teri dich

Diem khic biet gifts OLSR vi LSR II viec giao thtic OLSR host dung dva ten' viec met !them node mang cling tic v6i nhau tao nun *it kip phat chuyen tiep da diem MPR Mai node N trong mpg se Iva chip ra met tip cac node hang xem

cue no vio kip da diem MPR(N), cac node thuOc kip da diem nay se chuyen tiep cac g6i tin dieu !Nen (lucre giri to N Node kh8ng thuOc kip da diem cue N van xir 15r gel tin nay nhtmg se kluing chuyen tiep den the node khic

Hinh 2.3: Quy trinh chuyin dap goi tin see dung MPR

Liu diem du tien caa viec sir dung kip da diem la viec lam giam thieu cac thong dip quang ba phat tin trong raging, glop cho bAng th8ng duqc cai thin dang ke Lqi diem thir hai la viec giam duqc kich thuk cua g6i tin "Hello" vi no chi Itru tni cac thong tin lien quan ten cac node trong kip da diem dm n6

Hinh 2.4:OLSR ngiln chin vong kip bang see clung MPR

2.2.3 Giao thircdinh tuyenA0DV

AODV (Ad Hoc On-Demand Distance Vector) lit giao thirc dkra tren thuAt toan vector khoang each AODV ten thieu holt se ban tin quang bfi an thiet bang ckh

Phan Trung NgIlk

A08348

to ra cac tuyen ten co so theo you au, ngtrgc yeti viOc duy tri mOt dank sich

hoin chinh cac tuyen nhu thuot town DSDV

(b)CIp ins II/yen

Hinh 2.5: Qua trinh khbm phb tuyin trong AODV

Khi mOt node nguan muOn gai mOt bin tin den mOt node dich nio d6 vi kheng

biet rang di co met tuyen ding den dich do, no phii khai dAu met qui trinh Ichim

phi throng truyen N6 phit quing bi mOt gel y8u au tuyen (RREQ) den cac node

Mn con Cie node Mn con nay sau do se chuyen tiep gai you cAu den node lin con

khic ctia chimg Qua trinh ca tiep Ate nhu voy cho den khi co mOt node sing gian

nio 46 xic djnh dugc met tuyen "di, tuoi" de dat den dich AODV sir dung so thir

to dich de dim bio rang tit ca cac tuyen kitting lip va chira hiu het thong tin tuyen

hiOn tai Mai node duy tri so Sin tir cia no cling yeti mOt ID quing bb ID quing

bi dirge ting len mai khi node khai du met RREQ, vi cling yeti dja chi IP cia

node, xic djnh duy nhAt mOt RREQ Cling vii so tuAn to vi ID quing bi, node

nguiin bao gam trong RREQ hAu het so tan to hien tai cia dich ma no co Cic

node trung gian co the tri 16i RREQ chi khi nio ching co mOt tuyen den dich ma

so tuin to dich Wang ling Ian hon hooc bang so twin to chits trong RREQ

Thong snot qui trinh chuyen tiep RREQ, die node trung gian ghi vio Bing

djnh tuyen cia ching dja chi cis cac node lin con tir khi nhAn duqc bin sao dAu

tien cua g6i quing bi, theo do thiet I3p dirge met duimg din theo Mai gian Neu cac ban sao cim cimg met RREQ dirge nhon sau d6, cac goi nay se bj hu9 be MOt khi RREQ di dot den dich hay mot node thing gian yeti tuyen "du tuai", node dich (hoic node trung gian) dip an Iai bang each phit dart phucmg met gel dip Ling tuyen (RREP) ngtrqc ve node lan cjn ma tir do no thu dirge RREQ Khi RREP dirge djnh tuyen nguqc theo &rang din, the node bra dubng din do thiet lop the thuc the tuyen chuyen tiep trong Bing djnh tuyen cim chi node ma no nh#n dirge RREP Cic thuc the tuyen chuyen tiep nay chi thj tuyen chuyen tiep tich cue Can vii mOi thqc the tuyen la mot b0 djnh than tuyen co nhiem vu xoi cac dap the neu no Ichong dirge sir dung trong met died ban xic djnh Do met RREP chuyen flap tren dtrang din dirge thiet Iftp bai met RREQ nen AODV chi ho trq viec sir dung throng truyen doi ximg

Trong AODV, cac tuyen duct duy tri dieu kien nhu sau: Neu met node nguen chuyen ding, no phii khoi Ong lai giao thus }chain phi tuyen de" tim ra mot tuyen mai den dich Neu met node tren tuyen chuyen ding, node lin c#n luting len cim

no cho 5/ den chuyen Ong d6 va truyen met bin tin "Khai bio str co dwang thong" (met RREP khOng xic djnh) den mil node lin ejn tich cue Meng len de thong bio cho cac node nay xoa phin tuyen d6 Cic node nay thqc chit truyen met "Thong bio sur c6 duang thong" den cac node Ian can luting len Qua trinh cir tiep turc nhu v#y cho den khi dat den node ngulin Node nguOn sau d6 co the chop khai ding lai met qui trinh khim phi tuyen cho dich d6 neu mot tuyen yin can thiet

Ngoii ra, giao thirc nay sir dung bin tin HELLO dirge phit quing bi djnh ky be' met node de thong bio cho tit ca cac node khic va nhOng node Ian c#n cua no

Ck bin tin HELLO co the dirge sir dung de duy tri khi MIT kit n6i cue b0 cua met node Tuy nhien, viec sir dung bin tin HELLO la khong can thiet Cic node ling nghe viec truyen Iai g6i du lieu de dim bio ring yin dat den chOng ke tiep Neu kh8ng nghe dirge viec truyen lai nhu the, node co the sir dung met trong so

cac ky thuot, ke ca viec tiep nlitin bin tin HELLO Cic bin tin HELLO co the lief

ke cac node khic ma t(r do node di ding di nghe tin No, do do to ra khi ning lien kit Ion han cho mpg

Node

Node

(e) key dims bang en wean

4C-Cr i.er si•

lb) Troyer, dip &nu tuytn vol bang ghi tuytn

Phan Trong Nghia

A08348 2.2.4 Giao thircdinh tuyenDSR

Giao thfrc DSR (Dynamic Source Routing) li met giao thfrc dinh tuyen phin

Ang tir node ngwin Trong d6, ctic node di dOng can duy tri b0 nher dem ve tuyen

chfra the node nguiin ma node di dOng nhon biet duktc Cic thqc the trong b0 nhet

dem ve tuyen dtrqc cop nh$t lien tuc

Hinh 2.6: Giao thec DSR

Giao thfrc nay bao Om 2 giai clop chinh: a) Khim phi tuyen va b) Duy tri

tuyen Khi met node di dOng gars met goi den met node dich nio do, tit& het no

phai tham vin bki nher dem tuyen de xic dinh 1a no dA co met tuyen de" den dich

chua Neu no co met tuyen chua het hieu lye de den dich, no se sir dung tuyen nay

de giri goi di Trii lai, neu khong co mot tuyen nhu the, no phii khiti Mu met qui

trinh khim phi tuyen bang rich phit qtuing bit mot g6i you cAu tuyen Bin tin you

cliu nay chfra ilia chi dich, ding yeti dig' chi node ngutin vi 56 nhOn clang duy nhOt

MOi node nhOn duqc goi nay se tien hinh kiem tra la no co biet met tuyen nao de

den dich kh8ng Neu khong, no them rho chi cua no vao Bing ghi dinh tuyen cua

gOi vi sau d6 chuyen tiep g6i teen cic than truyen ng8 ra De gioi han so yeu au

tuyen phit tren cic duong truyen nge ra cua node, met node chi chuyen tiep yen

au tuyen neu no chua biet yeu au d6 vi neu dist chi cos node di dOng chua xuitt

hien trong Bing ghi tuyen MOt dip (mg tuyen duqc to ra khi hooc la yeu cau

tuyen dot den dich hoc la khi no dot den met node trung gian chira trong Ix) nha dem tuyen cua n6 mot tuyen den dich chua het hieu loc Den hie gel co the dot den dich hay den mot node trong gian nhu the, no chfra mot Bang ghi tuyen cho biet se) titan ty ching dfi UM qua

Neu node too ra dfip ling tuyen la dich dil no dAt Bang ghi tuyen chin trong yeu cAu tuyen vio dap ling tuyen Neu node Wang ling la melt node trung gian, no gin them tuyen trong b0 nhe dem dm no vito Bing ghi tuyen va sau do to ra mot dap ling tuyen De tra ve dap ling tuyen, node tacmg ling phai co mot tuyen de khai dAu Neu n6 co mot tuyen de khai dau trong b0 nha dem tuyen cua no, no co the sir dtmg tuyen do Trai lei, neu cac throng truyen doi ximg dirge ho fro, node

co the khei dAu mot qua trinh kham phi tuyen cua no va tiep We gni di dip ling tuyen tren mot yeu cau tuyen mei

Viec duy tri tuyen dirge hotin thimh thong qua sir ding cac gen kli tuyen (RERR) vi cac ban tin xfic nhon Cfic gel 18i tuyen doge to ra a mot node khi lap lien ket dfr lieu g0p so c6 diking truyen Node nguan luon Won bj climg khi mot tuyen bj cat dirt (co mot lien ket tren tuyen bj 16i) Khi nhfin dirge min gei ISi tuyen, ching bj loi se bj loai bo khoi b0 nha dem tuyen cua node va tat ca cac tuyen chin citing nay deu bj cat a diem d6 Ngoiti cac ban tin loi tuyen, cac ban tin xic nh(in dirge sir ding de xic mink so hoot dOng chinh xfic cua cac direng thong tuyen Cac bfin tin xic nhin nlur the bao gOm ca xfic nhon thy dOng (khi node di dOng co the nghe vier chuyen tiep goi a chang ke tiep tren tuyen)

2.2.5 Giao thircitinh toyenTORA

TORA (Temporally Ordered Routing Algorithm) la melt thuit town djnh tuyen phfin bto khong co vong leP va do thich nghi cao, dua tren khai niem dfio ngugc dtrong thong TORA dirge de xuAt cho moi trutmg not mang co tinh linh dOng cao N6 la mot giao thfrc khei phat tfr nguOn va cung cap da tuyen cho moi cfip node nguen/dich an thiet Nguyen 15, chit dgo trong TORA la djnh vi cac ban tin dieu khien deti vei moi ttip hop cac node gait yeti nai xfiy ra so thay del topo mpg De thoc hien dirge dieu nay, cac node can duy tri thong tin djnh tuyen ve de node ke

Om (chi mot ch(ing) Giao that nay thoc hien 3 chile 'tang co ban: Tgo tuyen, Duy tri tuyen, vi Xofi tuyen

Phan Trung Ngtila

A08348 Trong suet giai (loan too ra vi duy tri tuyen, cac node sir Ong mot tham so "do cao" thiet 13p met DAG (so des birth xo&n 6c) co g6c a node dich Sau d6, the duerng truyen dirge chi dinh mot huemg (luting len hay lining xueng) dtra tren tham

so do cao twang del cis cac node lin con Qua trinh thiet 13p DAG twang tv nhu qui trinh van tin/dip Ong trong LMR

Trong then gian met node di chuyen, tuyen DAG In phi va va vi3c duy tri tuyen can de thiet 13p lei mgt DAG co gee 6 cling dich do Khi duetng th8ng luting xuOng cue; cling bi sir co thi mot node to ra mot mirc tham chieu meri dtra vio mire tham chieu cim cac node lin con, phtii hqp hoot dOng co hi3u qul de phin ling loi sir co d6 mot each co clu true Cic dubng th8ng dirge dio ngugc de phin anh nhcmg thay doi trong vi3c thich nghi yeti mire tham chieu med Viet nay co hi3u qui giOng nhu sir dtio huerng cia mot hay nhieu dubng th8ng khi met node khong co cac dutmg thong !ding xueng Vigo dinh than la met you t6 quan tong deli yeti TORA do tham so "do cao" dOc 13p vol theri gian sir co dubng thong; TORA gii sir ring tit ca cac node deu co (king h6 deng b0 (thvc thi qua men nguen thbi gian ben ngoii nhu he thtmg dinh vi town ciu - GPS)

Clic tham so ctia TORA gem: Thai gian sir co duang thong,ID duy nhit cis node xic dinh mitt tham chieu maxi, Bit chi an phim firth, Tham s6 this tit truyen,

va ID duy 'that cia node Tham so this 3 the hien mire tham chieu met each co chop lqc MOt mist tham chieu man doge xic dinh m8i khi mitt node khong con dtremg th8ng luting xming cu6i cling do mr ce dui:mg thong Giai down xoa tuyen

cua TORA bao gem mot bin tin quing bi "Xoa tuyen" (CLR) trong toan mang de xoa cac tuyen kh8ng con hi3u lire

Trong TORA co met str bien dong tiem tang xay ra, d3c bi3t kin nhieu top hop cac node dang lien ket Ia phin hien dang bi xoa, cac tuyen dang xoa, va cac tuyen dang xay dung man Do TORA sir ding tea dO lien node nen bai toin bit can bang

dm no twang tir nhu bai loan tinh den v8 cling trong cac giao thisc dinh tuyen theo vector cis ly, ngotti trir cac hien dOng 11 tom then vi sir her tv tuyen cutti cling van dot dirge

2.3 Cic moil de dna ban nt.t trong ming MANET

2.3.1 Wong quan

Voi str tang nhanh ciut cic thiet IA di dOng re han, nho han, vit manh me han, mang MANET fro thanh mot trong cac mang duqc quan tam nghien ciru Day la kieu mpg tit t6 chit mei ket hqp lien ket khong day veri node di dOng mot dO cao Khong &Ong nhu cac mpg c6 day thong darting, chimg kh8ng c6 ha tang co djnh (cac tram ca so, cac diem quin li trung tam) Cic node hqp veri nhau thanh mot topo thay dei tuy y Sr filth host nay khien chimg duce quan tam cho mot so ling ding, nhu cac ling dung trong gam str nai topo mang c6 the thay doi nhanh de phan inh cic di chuyen hoot dOng ciut mot lye ltrqng, vit cic hoot dOng eau non nai ma cic mang ha tang có dinh c6 the khOng hoot dung Mang thy bien to to chic cling thich hqp cho cac hei nghi trice tuyen, nai ma cai d¢t mOt mang ha tang truyen thong tieu Mn theri gian vit chi phi cao

Cic mang thong thubng sir dung the node chuyen dung de mang cic chirc nang ca bin nhu chuyen tiep gai, djnh tuyen, vi quart ly mang Trong mang adhoc, cic chirc nang tor' duce tbArc hien bang each Ong tic cac node co kha nang Cic node trong mang MANET sir dung lien ket multihop: cic node ben trong vimg phn song cis node khic c6 the lien ket true tiep qua cic lien ket khong day, trong khi nhUng node kit& a xa phiti dins vio uric node trung gian Cie node

di &Ong c6 the di chuyen, rat gia nhop mpg, va cic tuyen can phai cjp nh#t lien tic phi hqp yen topo mpg dOng Vi du: node S c6 the lien ket veri node D bang each sir dung dm:mg di non nit& S-A-B-D Neu node A di chuyen ra ngoiti pham

vi dm node S, no se tim duang thay the den node D (S-C-E-B-D)

Phan Trung Nghia

A08348

Hinh 2.7: Lien kit gifia the node trong mgng MANET

Met lord cac giao thirc m6i de duqc phat trier cho viec tim kiem, cep ilk* the tuyen va cung cep lien ket giita cac diem au cu6i (nhtmg cho den nay giao thirc dtrqc de xuat van chua duqc chip nhen nhu la met chuen) Tuy nhien, cac giao thirc djnh tuyen men dkra tren viec hqp the giera the node a bi ton thucmg beri the cuec tin ding mei That khong may khi the giao thirc djnh tuyen duce di xuAt cho mang MANET kitting can nit& an yen de Wm met Han nita, yeti the dec firth efia chting nhu thieu cac diem trung tam, topo mang Ong, va cac gieri han ten mi cita node 'Jet ra thaeh thirc cho yen de bito m0 Nhieu nghien eau a ducre thtrc hien de chart va phfit hien the cuee tan Ong phi hoai the giao thirc dinh tuyen trong mang MANET, bao gOm bito mot the giao thirc djnh tuyen va the he thting phat hien xant nhep (IDS) Tuy nhien do met s6 li do ma the giii phfip duqc de xuAt top trung vao met s6 diem yeu bao met tir met gal phip tong quit la khong ding ke

2.3.2 Cfic diem yeu cea luting MANET

Voi cac dee tinh cua mang MANET trinh bay a tren dit det ra thach thirc cho cac giai phap bio met MOt se cac bien phip bito met hien tai cho mang truyen thong ter nen khong hieu qua khi trien khai trong mei truing MANET Do d6 cac nha nghien cuu a phfit trier cac gifii phfip mei hoec thay d6i the &Ai phap hien tai cho phir hqp v6i mang MANET Cie giao thirc dinh tuyen c6 the cluqc de xuAt de chin cac host &Ong co lop bang each bit cac node c6 lep tong tic Cic cc the kh6a quitn 15, hien nay thuang dqa tren the diem trung tam nai cung cep cac djch vtt nhu cc quan Chung nhert (CA) va may chit quan trong (KS) et!) the dtrqc thiet lip Mang MANET khong c6 the diem trung tam, the cc the kh6a quin 15, mei duqc phat trier de dap img cac you clu Khi the cong nghe phong ch6ng chi co hieu qua gieti hen, cac he thong phat hien (IDS) duce dui vao de bo sung cho cac

ea the bio met }chic Cfic diem yeu cis mang MANET:

• Lien kit khong day: sfr dung lien ket khong day lam cho mpg de bj tint thucmg khi bj tan ding nhu nghe tram va cic hanh dOng can thiep true tiep Khong giOng nhu mang c6 day, Ice tan ding kh6ng an truy nhap vat ly den mpg de thgc hien cac cuOc tan ding Hon nfra, mpg khong day c6 bang th8ng thip han so vai mang c6 day Ka tan cong co the lqi dung dac tinh nay de chiem dung bang thong cim mpg va a ding ngan can ket not binh thus ng glen cic node

chuyen dec lap Din den topo mang thubng xuyen thay d8i do do no kh6 co the phan biet duqc hanh vi binh thwang voi cic hanh vi bat thutng hay gay hai cho mang Vi du, met node gai thong tin phi ver tuyen co the la met node dec hai hoac cling c6 the don gian IA sir dung th8ng tin het han a met node binh thuong Han nova kha an di dOng ctla cic node c6 nghia IA chimg ta co the di chuyen chting, 4c biet la the node quan tang nhu server, duqc ban mat nhu trong mpg co day Cac node veri str bao ve vat lg khong tucmg ximg co the chili nil ro din den bj chitin gift vi

Ong tic van nhau Dieu nay din den mot node dOc hai co the a ding ter thenh met phan quart tang cua qui truth djnh tuyen va pha vo cac hoot dung mpg bang each kh8ng tuan theo the cloc tinh coa giao thirc Vi du met node co the es vi tri nhtr ling gieng yen cac node khac va tham gia vao

ca the quyet djnh quan tang, co the gay imh htrang ding ke den mang

• Thiau mgt tuyin phong tha ra rang: mang MANET khong co met tuyen phong this re ring, cic cuOc tan Gong co the den tir mai htrang Ranh gien phin chia gitta ben trong mang vi ben ngoiti la khong r8 ring trong mang MANET Vi du: no kW-mg co vi tri phi:mg din tot not ma cluing ta c6 the trien khai giam sat hm lugng va cic co the dieu kin& truy nhap Trong khi tat ca km lugng di qua switch, router hay gateway a mang do day, thi thong tin mang trong MANET duqc Olin tin qua the node chi c6 the they va nhan the gal trong pham vi truyen cim chting

• Gioi hpn tai nguyen: cic the ve tai nguyen la met diem you khac NO bao gom rat nhieu cac thiet bj trong mang MANET tir laptop den cac thiet

hi cam thy nhtr PDA vi dien tho3i di dOng Chong thuimg co kha nang tinh town va Itru trot khfic nhau d6 co the thinh tam diem dm cic cuOc tan ding mai Vi du: cic node di dOng thtrong nhanh het pin, no fret thinh muc tieu coa cac kieu tan eking cal tien nth: Sleep Deprivation Torture Han niin viec

Phan Trung Nghia

A08348 dua cac dac tinh bao mat meri vao man lam tang sv tinh toitn, lien ket va quan Ii tai Day la met thach th6c cho cac mpg bi han chat vat tai nguyen 2.3.3 Cac cuec tan cong vao MANET

Cac myc dich bao mat ctia mang MANET la tuang del giOng so veri cac mpg khitc dac trung beri tinh xiic thyc, ban mot, tan vgn, tinh sin sang, va khong thoiti thac Xic thvc lit cac yeu cAu xic minh thong tin eh danh cilia node ngutin Bio mat c6 nghia la chi duy nhat nhftng nguai hay 114 thong xic thvc c6 the doe va thvc thi cac chuang trinh hay dir lieu duqc bao vat N6 co the la cac thong tin nhay cam trong mang MANET, co the bi hit), nhanh han so vai cac thong tin khic Vi du: vi tri tap trung ciut ngiy horn qua se it nhay cam han so veri ngay horn nay Tinh town vgn nghia la thong tin kung duqc chinh sira hay phi hey beri ngueri dung khong xac thyc hay mai twang Tinh sin sang co the xem nhu nitng lyc cita mang de cung cap cac dich vu theo yeu cau Cie cuec tan cong DoS tra thinh mei

lo ngai lern cho nhftng ngueri quan tri mpg Trong quart sy, met cuec tan cong DoS thinh cong c6 the gay Mn that ve cung Ion, va cac cuec tan cong veri ky thuot tren trer thanh myc dich cita chien tranh hien dal CuOi ding, tinh kh8ng thoii thfic dam bito cac hoot dung duqc giao ph6 !thong the bi tir chei Trong mang MANET cac myc dich bao mat cita he thong co the thay dOi theo timg truerng hop (nhu thin binh, chien tranh)

Cfic dac tinh ciut mpg MANET lam cho chin% ter nen date bi Mn hai ben met s6 kieu tan cong mai Cac kieu tin cong co the dtrqc phan loci theo giao thirc mang

Tang (mg dung Thay doi der lieu, cac loci virus WI sau

Tang van chuyen Ngitp ltd tin SYN giao thirc TCP/UDP

Tang mang Ng#p lyt tin Hello, tan cong ho den (blackhole) Tang lien ket 0 lieu Guam sat, phan tich Itru luqng

Tang vat l5, Nghe tem, can thiep tich cyc

Met se tan cong c6 the xuAt hien a nhieu lap, vi du: lam nghen mpg 6 tang vat l5f, Iran ng#p gai Hello a lap mang, va tran ng#p geoi SYN a lap giao van tat ca de'u

la kieu tin cong DoS Chuang nay se tap trung vao cac cuec tin conga lap mpg

a) Ma hinh

Co the chia ke ten cong thanh hai nhom: ben tong va ben ngoiti Met ke tan cong ben ngoai khong phai la met ngtrai dung hqp phtip cua mpg, met ke tan cong ben trong la met node dugc xac thvc va la met phial cua co the djnh tuyen trong mpg MANET Citc thult toan dinh tuyen dien hinh dirge dOc trung bed tinh phin tan va hqp tic anh huang den toan be he timing Mk du met node tan ding ben trong mong MANET c6 the phi va lien kit mang Met node co the that boi, khong the thvc hien chirc ming cua no do met s6 li do nhu het nang lugng, hay do the cau ket trong mpg Cfic de dip cua node thfit boi la die biet nghi8m trong neu chfing la met phan cua tuyen khan cap hay bao mOt.That boi cua cluing thim chi co the anh huang den phan vung mpg, chin loi lien IA gifta cac node khfic tong mong MOt node co lip (selfish) c6 the anh huang xtiu den duy tri cac tai nguyen cua no Cac node co lip sir ding chinh cac dich vu cua cac node khac, nhung kh8ng dap lei Phan nay top trung vao the cuec tan cong dugc thvc hien bai cac node dee hai ma muc dich cua cluing la phi 0 the lien kit mang NhOng ke tan cong nhim den viec phi vet lien kit mang theo cac each dual day:

• Pha vas tuydn: chinh sira cic tuyen dang ton tai, to ra cac yang lip djnh tuyen, va gay ra viec chuyen tiep cac g6i tin lau han bang each sir dung tuyen kh8ng t6i uu hoic khong ten

• CO lap node: tien hanh co lop met hok nhieu node vii cac node khfic tong mang, phan Wing mpg

• Tieu hao tai nguyen: Mm gthm hien suet mpg, tieu hao bang th8ng mpg hoc tai nguyen cua cac node

Ning va ale ding nghiep sau khi phim tich cac cuec tat' cong ben tong chi:mg loi giao thin AODV, di chi ra rang de dot dugc cac muc dich hen

an phai dtra vio kha ming cua ke tan citing Theo do cac nhan t6 chinh kith huang den hieu suet cua met cues tan ding:

• Cong suit tinh man: dieu nay inh hieing n3 rang den kha Ming cua ke tan ding de can thiep vito met mpg Ding suet kh6ng can phii xac djnh vi tri de tham gia mong, nghe tem luu lugng rod chuyen lei cho cac mang may tinh hieu suit cao phan tich

• Khci Wing &lin khai: ke tan cong phan tin c6 the to met node den met Wing trail dim, vii met sv thay did kit qua tong cac kha !tang dui

Sv khfic biet nay co the anh huang den kha ruing nghe trem, den

Phan Trung Nghia

A08348 viec gay nghen mang met each hieu qui, va de tranh khoi viec bi vo hieu hoa (vi du: kha ning Mm nghen cua met node co the de ding bj chin, neu gay nghen bang each phan tin se kho khan hon trong viec ngtin chart)

• Kilm soot vi vi tri cos cic node tan ding co the jut huong ding ke den nhung gi chimg c6 them lam MOt ke tin cong c6 the bj han the viec dat cac node tan cong tai ranh giai cim met mang doi nghjch (nhung co the Itra chgn cac vj tri chinh xic khic), c6 the co ke hooch cho cac node cg the (vi dg: bit Iii the node a lath the bj b6 tang), hog c6 met vi tri c6 kha nal% de" tao ra mot vimg trai tham (nor ma mat de chiem quyen ring rai c6 the doge chap Ethan)

• Di Ong: tinh di ding thuong mang Igi sg gia tang sirc mgrth.(met node

di eking c6 the gift nguy8n vj tro Mg khic, tinh di Ong co the nem kh8ng cho met ke tan cling lien tuc nham vao mg node cu the Vi dg:

mg node di chuyen c6 the khong nhan tat ca cac g6i djnh tuyen gia moo doge bit tir ke tan cling Sun va ding nghiep da Vic djnh hien ttrgng nay nhu la met "rum nhan khOng hoin toad' Han nfta, hg tuyen

be rang ngay ca khi no giitm mire thiet hai do ke'tan cling, no lam sg phat hien them kh6 khan dr cac dau hieu cim met cuOc tan cong va phat sinh do ban chat tieing ciut mpg cang lam no trir nen kh6 phan biet hon Phitt hien tic dgng dm met node di dgng la met van de phirc tap

• Mzic dos trig nildp vdt ly, (bao gam kha nang bit va kha ning thgc hien gig eau true vat 15f)

Do ban chat thay del nhanh cim mpg MANET nen xfic djnh met mo hinh tan cong img dung lit kh6 Man Tuy nhi8n he thong c6 the dash gia qua met diti cac mo hinh de dga dac tnmg

b) Ccic dgng tin cong

Co the chia cac cuec tan cong thanh hai logi 11: chit dgng va thu eking

• Tan cling thu dgng

Trong met cuec tan cling thu Ong, met node khong xfic thgc &am sat

va mgc tieu lit tim kiem thiing tin ve mpg Nhftng ke tan cling khong lam

gi khac chi can lien kit yeti mgng Do do, chimg kh6ng phi ver lien kit hay gay ra cac nguy hiem true tiep den mpg Tuy nghen, chimg co the sir dgng

the thong tin lay duqc cho cac cups Mn cling nguy hiem ham trong Throng lai Vi du ye tan cong thy dOng: nghe tram va pilaff tich lair luqng

Tan cling nghe trom: con doge biet den la Mn cong cong khai, la

Ideu Mn cong the dOng dirge thtrc hien bai the node ben trong hoc ben ngoai Ke Mn cong co the phin tich cac g6i tin quang bit de lay

met s6 thong tin hfru dung ye mang

Phiin tich luu Wong: khong nhat thiet la mgt tan cling thy dOng

holn Man NO holm total c6 the tham gia vlo cac giao thee, hoc tim each kich thich lien ket gifts cac node Nheng ke tan cong co the sir dung cac ky thu3t nhu tim hating RF, phan tich tS, Itru lucmg, vi giam sat thai gian tucmg quan Vi du: nha viec phan tich thbi gian, no co the biet dirge hai g6i vao va ra kh6i mot node chuyen tiep r8 rang 6 thai diem t vi t+$ IA nhu nhau den tir cling

met !wing gal Phan tich hm luqng trong mang Aloe ea the dat dirge:

✓ Citc node dang ton Mi va vi tri elm chimg

✓ Topo cue mang

✓ Vai tro dm cite node

✓ Nguan vi dich cue cac lien ket hien Mi

✓ Vi tri hien Mi cim the ea nhan hay cac chirc nang a; the

• eat cling chit dOng

Day la cac cuk Mn cong gay ra bai thay dOi tr4ng thai khling xac [hire trong mang nhu DoS, chinh sea the goi tin, va tuong tir Cite cuOc tan Gong nay thubng dirge thue hien bai ngtrai dung hoes cac node dirge xic dux de host dOng ben trong mang Ching to co the phan loai Mn cong chit dOng thimh bOn thorn IA: drop, chinh sire, lam gia va Mn cong thiri gian Mot cuOc tan ding co the dirge phan loci a nhieu Whom

Ccic cuOc an cling Drop: the node dOe hai hay co lap drop tit ca the goi tin khong phai danh cho chimg Trong khi cite node dOe hai

nhim den vies pha ve ket not mpg, cac node co lop nhim den

viec bio ten tai nguyen cita n6 CAC cuec tan cong Drop co the chan the ket not diu cuOi giera the node, neu node drop IA met diem quan tong NO cong lam giarn hieu Ming mpg bang each liun cho the goi de lieu phai truyen lai, Mo ra cac clueing dinh tuyen mai de node dich khiing dirge tim thay, va Throng hr