Slide Toi Uu

7/31/2019 Slide Toi Uu

1/19

MN: CC K THUT TI U

ti: Gii thut di truyn nh tuyn thchng

Ging vin : TS. L Nht ThngSinh vin thc hin:Nguyn Th H Giang Nguyn Minh Tun

Lp:M11CQCK01-B


2/19

Ni dung bo coNi dung bo co

Tng quanTng quan Thut ton nh tuyn trn InternetThut ton nh tuyn trn Internet Tng quan v GaraTng quan v Gara

Hot ng di truyn to ngHot ng di truyn to ng Duy tr bng nh tuynDuy tr bng nh tuyn Tnh ton thch nghiTnh ton thch nghi

Thc thi lu lngThc thi lu lng Thc nghim kt quThc nghim kt qu Kt lunKt lun


3/19

TNG QUANTNG QUAN

Thut ton nh tuyn c xy dng da trn bng nh tuyn.Thut ton nh tuyn c xy dng da trn bng nh tuyn. Internet pht trin mnh cc thut ton cn phi c kh nngInternet pht trin mnh cc thut ton cn phi c kh nng

m rng v thch nghi cao.m rng v thch nghi cao. Trong chng ny chng ti trnh by v thut ton GENETICTrong chng ny chng ti trnh by v thut ton GENETICADAPTIVE ROUTING ALGORITHM (GARA)ADAPTIVE ROUTING ALGORITHM (GARA) Duy tr thay th cc tuyn s dng thng xuynDuy tr thay th cc tuyn s dng thng xuyn

Cn bng tiCn bng ti


4/19

THUT TON NH TUYN TRNTHUT TON NH TUYN TRNINTERNETINTERNET

T thi k s khai ca Internet, thut ton khong cch vectorT thi k s khai ca Internet, thut ton khong cch vectornh tuyn da trn thut ton Bellman-Ford (Bellman, 1957,nh tuyn da trn thut ton Bellman-Ford (Bellman, 1957,Ford v Fulkerson, nm 1962.Ford v Fulkerson, nm 1962.

Giao thc nh tuyn (RIP) (Hedrick, 1988) da trn thut tonGiao thc nh tuyn (RIP) (Hedrick, 1988) da trn thut tonkhong cch vector vi s liu m bc nhy c thngkhong cch vector vi s liu m bc nhy c thngc s dng ngay c trong cc mng nh ti a phng.c s dng ngay c trong cc mng nh ti a phng.

Nhng im hn chNhng im hn ch Chi ph qung b lnChi ph qung b ln Kch thc bng nh tuyn lnKch thc bng nh tuyn ln S lng gi tin gi i nhiuS lng gi tin gi i nhiu


5/19

Tng quan v GARATng quan v GARA

Thut ton nh tuyn di truynThut ton nh tuyn di truynthch ng (GARA) l mt thutthch ng (GARA) l mt thutton nh tuyn s dng hotton nh tuyn s dng hotng di truyn to ra ccng di truyn to ra cctuyn lun phin trong bng nhtuyn lun phin trong bng nh

tuyn.tuyn.N c da trn cc thut tonN c da trn cc thut ton

nh tuyn ngun.nh tuyn ngun. Mi node c mt bng nhMi node c mt bng nh

tuyn cha mt b cc tuyntuyn cha mt b cc tuynng lun phin.ng lun phin.

Thut ton quan st tr caThut ton quan st tr cacc tuyn ng thng xuyncc tuyn ng thng xuyns dngs dng


6/19

Hot ng di truyn to ng (PGO)Hot ng di truyn to ng (PGO)

Vi thut ton GARA, cc hot ng di truyn to ng nhVi thut ton GARA, cc hot ng di truyn to ng nht bin ng v lai ghp ng c thit k to cct bin ng v lai ghp ng c thit k to cctuyn c th lun phin nhau da trn thng tin v topo mng.tuyn c th lun phin nhau da trn thng tin v topo mng.

Hot ng t bin ng s gy nn s xo trn v tuynHot ng t bin ng s gy nn s xo trn v tuynng to ra mt tuyn lun phin khc. Hot ng laing to ra mt tuyn lun phin khc. Hot ng laighp tuyn s trao i cc nhnh nh trong tuyn gia mtghp tuyn s trao i cc nhnh nh trong tuyn gia mtcp tuyncp tuyn

C hai loiC hai loi t bin tuynt bin tuyn Lai ghp tuynLai ghp tuyn


7/19

t bin tuynt bin tuyn

t bin tuyn s to ra mt tuyn lun phint bin tuyn s to ra mt tuyn lun phin Qu trnh t bin tuyn da trn cc bcQu trnh t bin tuyn da trn cc bcsau y, vi r l tuyn gc v r l tuyn sau y, vi r l tuyn gc v r l tuyn c t binc t bin

Chn ngu nhin mt node t binChn ngu nhin mt node t bin nnmm

trong tt c cc node trn tuyntrong tt c cc node trn tuyn rr, tr node, tr node

ngun v node chngun v node ch Chn ngu nhin mt node khc nm t ttChn ngu nhin mt node khc nm t tt

c cc node ln cn ca node t bin nmc cc node ln cn ca node t bin nm(nm).(nm).

Khi to mt ng ngn nht r1 t nodeKhi to mt ng ngn nht r1 t nodengun n node nm v mt ng ngnngun n node nm v mt ng ngn

nht r2 t node nm n node ch.nht r2 t node nm n node ch. Nu khng c s trng lp ca cc nodeNu khng c s trng lp ca cc node

trong r1 v r2 th chng c ni vi nhautrong r1 v r2 th chng c ni vi nhauv to thnh tuyn t bin r = r1 + r2. Nuv to thnh tuyn t bin r = r1 + r2. Nuc s trng lp th tuyn b hy vic t binc s trng lp th tuyn b hy vic t binxem nh khng c thc hinxem nh khng c thc hin


8/19

Lai ghp tuynLai ghp tuyn

Qu trnh lai ghp tuyn s trao i ccQu trnh lai ghp tuyn s trao i cc

tuyn con gia hai tuyntuyn con gia hai tuyn

thc hin c lai ghp, cp tuyn phi thc hin c lai ghp, cp tuyn phi

c cng node ngun v chc cng node ngun v ch

Qu trnh lai ghp c s dng vi ccQu trnh lai ghp c s dng vi cc

cp tuyn r1 v r2 theo cc bc saucp tuyn r1 v r2 theo cc bc sau

Chn mt b node Nc c xut hinChn mt b node Nc c xut hin

tronng c r1 v r2 (tr cc node ngun vtronng c r1 v r2 (tr cc node ngun v

ch) lm cc im c th ct lai ghpch) lm cc im c th ct lai ghp

Chn ngu nhin node nChn ngu nhin node ncc t Nt Ncc lm lmim ctim ct..

Hot ng lai ghp c thc hin bngHot ng lai ghp c thc hin bng

cch trao i tt c cc node sau nodecch trao i tt c cc node sau node

nc gia r1 v r2nc gia r1 v r2


9/19

Duy tr bng nh tuynDuy tr bng nh tuyn

Bng nh tuyn cha 5 trng l:Bng nh tuyn cha 5 trng l:

ch, tuyn, tn s, tr v trng sch, tuyn, tn s, tr v trng s

Vi mi ch, ta c mt b ccVi mi ch, ta c mt b cc

tuyn lun phintuyn lun phin

Tn s ca mt tuyn xc nhTn s ca mt tuyn xc nh

s gi tin gi n ch c ss gi tin gi n ch c s

dng tuyn dng tuyn

Trng tr lu tr truyn thngTrng tr lu tr truyn thng

ca gi tin c gi trn tuynca gi tin c gi trn tuyn

Trng s ca mt tuyn cTrng s ca mt tuyn c

tnh ton bng tr truyn thngtnh ton bng tr truyn thng

ca nca n

ch Tuyn Tn s Tr Trng s

2 (1 3 2)* 7232 50 0.7

(1 3 4 2) 2254 60 0.2

(1 3 4 5

2)

1039 70 0.1

6 (1 8 6)* 20983 100 0.4

(1 10 11

6)

34981 105 0.6

8 (1 8)* 30452 40 0.9

(1 7 8) 3083 40 0.1


10/19

Duy tr bng nh tuynDuy tr bng nh tuyn

Trong bng ny, cc tuyn c nh duTrong bng ny, cc tuyn c nh du

(*) l cc tuyn mc nh, l cc tuyn ngn(*) l cc tuyn mc nh, l cc tuyn ngnnht da trn tham s hop-count. Ban u,nht da trn tham s hop-count. Ban u,bng nh tuyn trng rng.bng nh tuyn trng rng.

Khi cn gi mt gi tin v nu khng cKhi cn gi mt gi tin v nu khng ctuyn n ch th mt tuyn mc nhtuyn n ch th mt tuyn mc nh

c to ra bi thut ton Dijkstra cc to ra bi thut ton Dijkstra ca vo bng nh tuyn.a vo bng nh tuyn.

Sau khi gi mt s cc gi tin trn mtSau khi gi mt s cc gi tin trn mttuyn, ta gi mt gi tin quan st trtuyn, ta gi mt gi tin quan st trtruyn thng ca tuyn.truyn thng ca tuyn.

Gi tr thch nghi c tnh sau khi nhnGi tr thch nghi c tnh sau khi nhnc tr li.c tr li.

Sau khi quan st, PGO c s dng viSau khi quan st, PGO c s dng vicc tuyn vi xc sut xc nh to cccc tuyn vi xc sut xc nh to cctuyn lun phintuyn lun phin

ch Tuyn Tn s Tr Trng s

2 (1 3 2)* 7232 50 0.7

(1 3 4 2) 2254 60 0.2

(1 3 4 52)

1039 70 0.1

6 (1 8 6)* 20983 100 0.4

(1 10 11

6)

34981 105 0.6

8 (1 8)* 30452 40 0.9

(1 7 8) 3083 40 0.1


11/19

Tnh ton thch nghi v la chnTnh ton thch nghi v la chnq

Mi nt nh k gi cc gi tin truy vn chm trMi nt nh k gi cc gi tin truy vn chm tr quan st tr truyn thng dc theo tuyn quan st tr truyn thng dc theo tuynngng ..

q Sau khi c c tr ca tuyn, gi tr trng s caSau khi c c tr ca tuyn, gi tr trng s ca

tuyn c tnh ton theo cng thctuyn c tnh ton theo cng thc

=

Sji

iiw

/1

/1

=

Sji

ii

d

d

/1

/1 di : tr tuyn i

q Bi v ta cn c mt trng s wi ln hn cho tr ditruyn nh hn. Do , mt tuyn vi tr nh hns thng c s dng gi gi tin.


12/19

Thc thi lu lngThc thi lu lng1. trng thi khi to, bng nh tuyn trng rng .1. trng thi khi to, bng nh tuyn trng rng .2. Nu bng nh tuyn khng cha tuyn c c ch2. Nu bng nh tuyn khng cha tuyn c c ch

n cho gi tin c to th mt tuyn mc nh sn cho gi tin c to th mt tuyn mc nh sc to ra bng cch s dng thut ton Dijkstra vc to ra bng cch s dng thut ton Dijkstra vtuyn c a vo bng .tuyn c a vo bng .

3. Sau mi ln nh gi trng s, hot ng di truyn3. Sau mi ln nh gi trng s, hot ng di truync gi li vi xc sut xc nh to cc tuync gi li vi xc sut xc nh to cc tuynlun phin trn bng nh tuyn.lun phin trn bng nh tuyn.

4. Nu kch thc ca bng nh tuyn vt qu gii4. Nu kch thc ca bng nh tuyn vt qu giihn, chng ta thc hin php chn lc gim kchhn, chng ta thc hin php chn lc gim kchthc ca n. .thc ca n. .


13/19

Thc nghim kt quThc nghim kt qu

q V d minh ha l th nghim ca Corne, Oates vV d minh ha l th nghim ca Corne, Oates vSmithSmith

q Trong v d minh ha di y, mng c sTrong v d minh ha di y, mng c s

dng c 20 nodedng c 20 node

q Thut ton GARA vit bng m PascalThut ton GARA vit bng m Pascalq M phng c chy trong 3000 giy

nhn c cc kt qu. ti mi node trongmng, gi tin d liu c khi to ngu

nhin ti mt thi im xc nh c phnb theo hm m. ch n ca gi tin cla chn ngu nhin t cc node c biudin l cc hnh trn c t xm. Xc sut

t bin l 0.1 v xc sut lai ghp l 0.05


14/19

Thut ton GARA vit bng mThut ton GARA vit bng mPascalPascal


15/19

Thi gian n ca gi tinThi gian n ca gi tin

GaraGara t c nhiu thit c nhiu thigian n trung bnh nhgian n trung bnh nhhn ca cc gi tin giaohn ca cc gi tin giaotip hn so vi RIP, SPFtip hn so vi RIP, SPFv SPF thch nghiv SPF thch nghi ..

SPF thch nghi trc tipSPF thch nghi trc tip

quan st tr truynquan st tr truynthng ca lin kt lthng ca lin kt lkhng hiu qu trongkhng hiu qu trongmng ti nhmng ti nh ..


16/19

Chi ph nh tuynChi ph nh tuyn

GARA t c thi gian in nh hn vi chi phi truynthng t hn nhiu

=> thut ton GARA t ckhong 20% thi gian ntrung bnh so vi khong thigian ca RIP v SPF. iu nyngha l cc gi tin c gi

bng thut ton GARA s n

ch nhanh hn 5 ln so vi ccgi tin c gi bng cc thutton khc


17/19

Tnh trng ti ca lin ktTnh trng ti ca lin kt

GaraGara SPFSPF RIPRIP

dy ca mt lin kt l vit tt ca chiu di hng i trung dy ca mt lin kt l vit tt ca chiu di hng i trungbnh ca n.bnh ca n.

GGaraara t c t hn nhiu trn khng lin kt, c bit l trnt c t hn nhiu trn khng lin kt, c bit l trncc lin kt 11 13 19.cc lin kt 11 13 19.


18/19

Kt lunKt lun

Gara nhn ra mt nh tuyn thch ng hiu qu vi chi

ph truyn thng t hn bi cc c ch sau y:

N quan st tr truyn thng ca cc tuyn ngthng xuyn s dng.

N to ra mt thit lp ph hp ca cc tuyn ng

thay th s dng cc nh khai thc di truyn.

N phn phi cc gi d liu gia cc tuyn ng thay

th, nhn ra mt c ch cn bng ti gia chng.


19/19

Xin chn thnh cm n!Xin chn thnh cm n!

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