MOt kieu tan eating lam gia khic treiTh MANET lit ten cong nhiem dqc
bo dinh tuyen. MOt node c6 the cop nhOt bang cim no vai the thong tin djnh tuyen trong cac gei ma no nghe dirge, ngay ca khi no kh8ng a tren tuyen cua the gai. Ke tan cling co the lqi dung d#c diem nay de du d'Oc cic tuyen den node min nhan bang each giri the gen th8ng tin djnh tuyen gilt, lam cho cac node ling gieng 4p nhot bang dinh tuyen cua chting sat.
Min ding theri gian: Ice tan cling thu but cite node khac bang each lam cho no xuat hien gan hen cac node so yeti dive te. Cac cuec tan cling DoS, tin cling dim djp, vi tin cling tran ng#p hello sir dungi" ,k thuOt nay. Tin cling clklp xay ra trong giai dogn kham pha tuye'n. Trong tat a cac giao thin djnh tuyen theo yeu au ten tgi, met node can met tuyen quang ba the tin RREQ vi mai node chi chuyen tiep tin RREQ den dim tien de han the chi phi tin ng#p tin. Vi the, neu tin RREQ dirge chuyen tiep bai Ice tin tong dau tien den dich, ac tuyen bao gam ca ke tan cling se dirge kham pha thay cho cac tuyen gia hi. Citc cuk tan cling clOn clop co the thkrc hien theo met s6 each: bo qua skr chfun tie a ma Vic thtrc tin MAC hooc cac lap dinh tuyen, cac coo ten cong wormhole, gift hang dui truyen tai cua cac node khac day, truyen cac gei a cling suet truyen tai kheng day cao hon. Tan cling tan nip hello la met kieu tan cong 'chic lam cho ke tan cling thu hit mOt so tuyen. Trong met s6 the giao thirc djnh tuyen, cac node quang bit the geoi Hello den the node ling gieng phat hien. Cfic tin nay doge nhan bai the node lien ke (one-hop), nIumg kitting dirge chuyen tiep den cac node xa hon. Ke dm cling cluing ba cac g6i Hello vai tong suet truyen tai du rang de mai node nh3n goi Hello cho rang node ke thu la ling gieng cua n6. NO hieu qua dOi vai ca cac giao thirc dish tuyen chit img va phin img trong MANET.
MOt logi tin ding nguy hiem han nfta trong MANET la ten Gong wormhole cling tic. O kieu nay ke tan ang nhOn cic gen tai mOt diem trong mgng, cac throng ham chimg tao den mOt ke tan ding
khic a mOt diem khac trong mang, sau da phan h6i lai chimg a ben trong mang tir diem cuei can nay. Cac g6i dugc girl beci duimg ham ch#rt the g6i chuyen tiep bang cac tuyen da Wok nhu duel hinh vi no mang lai cho cac node tan cong mOt lqi the cho cac cuOc tat' ding trong Wong lai.
Hinh 2.9: Tiin cong Wormhole
Tir d6 the goi tin girl qua dui:mg ham ding ttrcmg ttr nhu cac g6i giri bin the node binh thtrOng, thueng kh6 phat hien duce the ke tan
cong wormhole bang cac tiep con chi sir dung phan mem nhu the he thOng phat hien xam nhop (IDS). D6 la li do tai sao cac kiem sofit
g6i (mOt vai thong tin duqc them vao mOt goi duce thiet ke hart
the khofing tech truyen tai cho phep tei da cue g6i) duqc de xuat phong cheng cac cu'Oc tan cong wormhole.
2.3.4. Cie bien pluip 461 phe
N6i chung, tien hanh ngan ch4n sg them hiep a not co the (cac giai phap chit dOng), tim each phat hien va doi ph6 khi ngim ngira Ichong hieu qua (cac giai phap phan Ong). Dual day la mOt s6 giai phip chit dOng va phan Ong duqc de xuat cho mang MANET.
a) Ccic thuen phong Bcio mat dinh tuyin
MCA so cuOc tan clang dugc nOi den a tren co the tranh dugc bang each them
cac ky thuot xac thgc trong giao thirc dinh tuyen. tuang chinh a day la dam bito tat ca cac node main tham gia vao qua trinh dinh tuyen phai la cac node
Phan Trung A08348 dirge xfic thuc; do IA cac yeu to ding tin coy trong mpg de host dOng theo cac quy tic cua giao thirc. Xic thuc nen dirge thuc thi trong suet cac giai doan djnh tuyen, nhir do ngin ngira cac node khong xfic thuc (bao gam cac ke tin cong) tham gia vao qui trinh djnh tuyen va the cuOc tan ding tien Myth tir dinh tuyen. Xfic thuc c6 the dirge cung cap dim ten cac kb:Sa e clang khai ho#c mat mA dal ximg. Trong cac Crating hgp twee day, the node cap cac chic 14 , se ket hgp veri cac tin dinh tuyen. Cfic chit k5, c6 the dirge xfic nhon ben node khac, sung cap mot bing chting an tan cho djnh danh ciut nguiyi girl. Bing chting se veri cac d#c tinh tucmg to c6 the dirge xiy dung bang each sir dung ma hos kh6a bio mat nhu MAC.
Viet sir dung mA h6a den thiet bj am thy co mot yin de' lien quan: sir can thiet cim mot co the cho phop phitt, trao dai, va thu hai cac khem. Kheya quilt 19 trong MANET kh6 khlin hen so veri mang co day do sir yang m#t cua ha dug hose trung tam quan 19 cac xfic thuc. Kh8ng co cac diem re rang not co the d#t cac dich vu nhu co quan chimg than (CA) hose cac may chit quan tong (KS), va phan 16n cac giii phip dirge de xuat cho den nay deu dua trer' cac huge do nai ma toitn b0 hg thOng kh6a quin 15, dirge trii ra den mot Lap con cac node di dOng.
Cfic huge a dirge de xat cho den nay chit yeu la cac giao fink thoa than kh6a phin tan nhu lugs d6 co dies hai-benDiffie-Hellman (DH). MOt vai cong trinh dA ma rOng giao thirc co bin len cac phien bfin n-ben, trong melt each ma n-node e6 the thiet lap mot kh6a chung cho cac lien kat nh6m. Cie giao thirc trao dai kheya mA hem (EKE) cling dal thich ling trong mang MANET. Cac huge
de nay dirge de xuat voi mire dich cho phep hai ben tho ra melt kh6a chung dii han tit mot mot khiu chung (thuerng dui entropy thAp silt do do de bi tan thutmg de" doin ac cac tin Gong). Melt d#c diem chung cim tat ca the phuong an net)
can (DH, DH chung, EKE...) lit melt sty gia trj ban du phiti dirge Chia se bid tit
ca cac node truerc khi giao thirc co the dame sir dung. Thuang dirge Mat den
nhu Ifi van de "bootstrapping" va no di nhan dugc st ir quan tam hgp 15, trong nhcmg atm gin day.
Su phfit trier cfia cac co se: ha tang kh6a cong khai d#c Melt phi' hgp veyi mang MANET dA fret thitnh mot de tai tong dune nghien tiro trong nhitng tam qua. PhAn lam cac giii pap dun ten melt CA phin ph6i dua ten mA hos nguang (threshold). Vi du: trong melt huge des dugs de xat, mot tap con cac node dirge biet den nhu 1a "cac may chit" &nth dOng chung thin melt CA. Mai khOa cong Thai thuOc ve melt node mang dirge Chia thanh n this se vi phial
phOi girls cac may chit n. MOt so k<n cua the may chit duqc you eau de 14 vao mijt chimg chi. MOi may chit tao ra molt cha ky rieng va thu th#p cac chit IcY rieng khac duqc tao ra bai cac may chit khfic. Trong dieu kien toin cuc, Itrqc 6 nay de march de chtmg Iii bfit Ict kb the nit° nhi}ng kit c6 the thee hip kheing hart k-1 node. MCA (Mobile Certificate Authority) la mOt giii phitp ttrcmg tkr ket hgp *It so tieu chi nhu vi tri volt 19, dolt diem tinh town, trien khai cac bien phap bao mitt, va tucmg ttir cho viec Iva chgn cac node se hogt dtjng nhu IA may chit.
b) Phat hien xam nkip
Tir khi cac ky thuitt ngfin ch#n dat duqc hieu qua him chit va cac xam Stop mai lien tuc xu.4t hien, IDS tray thinh mOt phfin khong the thieu ctia hg th6ng bao mat. IDS duqc gioi thieu de phat hien cac Wirth vi vi phgm chinh sach bao molt bing each giam sat the hogt dOng he thong VI dOi pho lai nhiing xam nhop xuAt hien. Neu phat hien mOt cuijc tan cong vao ben trong mgng, mOt phan irng co the duqc thuc hien de ngfin chOn hooc giam thieu thiet hgi cho hg thoing. IDS cling nhu cung cap thong tin ye cac Icy thtult xam tillgp, giep tang cuang str hieu biet ve the cutjc tan c8ng ye thong bito cac guy& djnh de phong cluing va giam nhg.
Mkic de c6 nhieu he thOng phat hien lam nhop cho mpg co day, chin% khong don gian de irng dung vao MANET. Cic d#c tinh khic biet cealVIANET lam cho cac hg thOng ph& hien xam nhop thong thtrimg khong hieu qua trong moi truang nay. Do do gtm day cac nhi nghien thu dA lam viec de phat trien cac hg thong phat hien xam nhap mai cho MANET, hoc chinh sira cac hg thOng hien thai de ling dung duqc trong mpg MANET. Dual day la cac icy
thuot phat hien xam nh#p Ichic nhau dtrqc de xuat cho mpg MANET. • Phat hien xam nhOp dip vao dole tinh
MOt trong cac k9 thuftt phat hien 'dun nhop thui:mg duqc de xufit cho truing MANET la phat hien xam nh#p dtra vao d#c tinh, the xam nhg'p duct phat hien nhu cac hinh vi vi pham thai gian chay cea d#c tinh giao thirc djnh tuyen. Ky thtult nay duqc ip dung cho mOt logt cac giao thirc djnh tuyen tren MANET nhu AODV, OLSR, DSR. MOi giam sat martg sir dung mqt may tinh tang Ghee (FSM) de not it cac d#c tinh cea AODV, d#c biet la qua trinh kham phit tuyen, vi duy tri mijt bang chuyen tiep cho nuii node giiun sit. MOi tin RREP vi RREQ trong phgm vi giam sat mpg
Phan Trung Nghia A08348
duqc gitim sat trong mot luting you cau-tra led a kiOm tra cac tinh huong nhu the got yeti eau tuyen c6 dugc chuyen di bet node kO tiep hay khong,
ligu cac gei tni leti tuyen c6 bj chinh sira tat duang diti hay thong... Khi mot giam sat mang can th6ng tin ve cac tin nhin three hoic cac node khic kheng nim trong pham vi cos no, no ca the hot cac giam sat mang hang x6m.
Trong DEMEM, mot IDS Olin phei vi cong the dugc mo to 6 de men node dugc giam sat 136i the node hang x6m mot bulk trong giao thin djnh tuyen OLSR. Ngoai giam sat hang xem mot btrec, cac hang xem hai huge c6 the trao ai dit liOu c6 bang chaing dAy du ve cac vu )(am nhip. Deng gap chinh cua DEMEM, nhu the the gia di tuyen bO, la de" gigi thiOu cac tin IDS dic biOt gitip phat hiOn.
HO thong phat hiOn dga teen dic tinh thubng dugc sir dung de phat hiOn cac thay dOi va cac cuOc tan cong gia mao. Tuy nhien, ky thu3t nay khong the phat hion cac cuOc tin cong thong vi pham the dic tinh giao thgc trim tiep (cac Bien the cua DoS thuOc lotti nay). Vi li do do, Huang va cac d'eng nghi'Op di de xuAt mot IDS sir dung ky thuit dga tree dic tinh cua cac cuOc
tan cong vi pham cac dic birth cua AODV men each trgc tiep va mot ky thuit dga tren sit bit thubng cho cac foal tan cong kit Film DoS. MOt so nha nghien ciru de xuAt b6 sung them mot cong eta chit 14, trong twang lai de phat hiOn cac cuoc tan cong DoS thong the IA phat hiOn bgi hg thOng dua tren FSM ma rOng cho giao thin djnh tuyen OLSR.
• Phat hiOn xim nhop dua tren stir bit thubng
Ky thuit nay me to cac d'Au hiOu hanh vi binh thubng cua hg thong, nhu sir dung tilt sO cua cac ionh, sir dung CPU cho cac chucmg trinh, va twang At N6 phat hiOn cac xiim nh3p bit thubng (vi du: do sai lOch fir cac mAu
hanh vi birth thubng). Citc ky thuit khac di duqc sir dung phat hiOn sg bat thuong, vi du: cac phucmg phap thOng ke, cac ky thuit tri tug thin tao khai the dOr liOu va cac mang thAn kinh. Thatch thirc Ign nhat la djnh nghia hanh vi binh thubng. Minh vi binh thubng co the thay dei theo thbi gian vi cac hg thong IDS can phiti thich (mg de phi' hqp. D6 la met trong nhOng li do sai tich cgc, cac host dOng binh thubng bj phitt hiOn nhu cac himh dOng bit thubng bed IDS, 0 the cao trong the phat hiOn dua ten skr bat thubng.