Mc LcCHNG 1 TNG QUAN V NS-221.Gii thiu v ci t NS-221.1Gii thiu v NS-221.2Ci t NS-221.3Chy mt chng trnh NS-232. Kin trc ca NS-232.1 Gii thiu32.2 Cc c tnh ca NS-243. Cc bc c bn trong m phng kch bn trong NS-243.1 Khi to v kt thc43.2 nh ngha cc nt v mng lin kt53.3 Khi to node73.4 Khi to link83.5 Khi to Network Agents83.6 Cc loi traffic93.7 Cc dch v c bn trong internet113.8Tracing123.9Routing123.10 M phng mt mng khng y trong NS-213CHNG 2: KT QU M PHNG CA BI TP LN161. bi162.Chng trnh m phng173.Hnh nh demo21

CHNG 1 TNG QUAN V NS-21. Gii thiu v ci t NS-21.1 Gii thiu v NS-2NS-2 l phn mn m phng mng iu khin s kin ring r hng i tng, c pht trin ti UC Berkely, c vit bng ngn ng C++ v Octcl. Bn li ch ln nht ca NS-2 phi k n l: Kh nng kim tra tnh n nh ca cc giao thc mng ang tn ti. Kh nng nh gi cc giao thc mng mi trc khi a vo s dng. Kh nng thc thi m hnh mng ln m gn nh khng th thc thi trong thc t. Kh nng m phng nhiu loi mng khc nhau.Mc d NS-2 l phn mn m ngun m c sn cho c nn Window v Linux, nhng trong bi tp ny chng em thc thi NS-2 trong mi trng Linux.1.2 Ci t NS-2u tin ta phi ci t h iu hnh Linux, y trong bi tp ny s dng Linux Ubuntu 8.04 cho vic ci t NS-2. Khi ng Ubuntu 8.04. Trong qu trnh ci t phi m bo vic kt ni vi internet. Sau sao chp file ns-allinone-2.33.tar.gz va ti xong trong th mc Home Folder. Chng ta thc hin vic cp nhp cho h iu hnh Ubuntu v ci t C, C++ complier. Chng ta vo Applications/Accessories/Terminal. Ln lt g tng lnh sau y. (Nu c yu cu nhp password thi nhp vo password ng nhp vo my).1. Sudo apt-get update2. Sudo apt-get upgrade3. Sudo apt-get install build-essential4. Gcc-v5. Make-v Sau g lnh tar-xzvf ns-allinone-2.33.tar.gz Di chuyn vo th mc ns-allinone-2.33 bng cch g lnh: cd ns-allinone-2.33 G lnh tip theo: sudo apt-get install build-essential autoconf automake libxmu-dev. G lnh ./install v chng ta ci t xong.

1.3 Chy mt chng trnh NS-2 chy mt chng trnh m phng NS-2, di chuyn vo th mc ns-2.33, thng qua Terminal gi chng trnh ns bng lnh ns .V d: chy file m phng CSTSL.tcl trong th mc ex trong ns-2 ta g nh sau: Ns ns-allione-2.33/ns-2.33/tcl/ex/CSTSL.tcl2. Kin trc ca NS-22.1 Gii thiuNS l mt phn mn hng i tng s dng hai ngn ng C++ v OTcl. Phn d liu v phn iu khin c tch bit. C++ cho phn d liu: X l mi gi tin, thc thi nhanh chng, chi tit ha, b sung y cho vic iu khin, cc thut ton i vi b d liu ln. OTcl cho phn iu khin: M phng cc cu hnh cho kch bn Thc thi nhanh chng, d dng cu hnh li Thao tc i vi cc i tng C++ hin ti Vit m nhanh chng v d dng thay iDng C++ : M phng giao thc chi tit yu cu ngn ng lp trnh h thng Thao tc trn byte, x l gi, thc thi thut ton Tc thi gian thc l quan trng nht Thc thi bt k vic g m cn phi x l tng packet ca mt lung. Thay i hnh vi ca lp C++ ang tn ti theo nhng hng khng c lng trc.V dng OTcl : M phng nhng thng s hay cu hnh thay i Tham d nhanh mt s tnh hung Thi gian tng tc (thay i m hnh hay chy li) l quan trng Cu hnh, thit lp hay nhng g ch lm mt ln. Thc hin nhng ci m ta mun bng cch thao tc trn cc i tng C++ ang tn ti.2.2 Cc c tnh ca NS-2NS-2 thc thi nhng tnh nng sau: Cc k thut qun l hng i Router nh DropTail, RED, CBQ. Multicasting M phng mng khng dy c pht trin bi Sun Microsystems + UC Berkely (D n Daedalus). Thuc mt t (di ng, ad hoc, GPRS, WLAN, BLUETOOTH), v tinh. Chun IEEE 802.11 c th c m phng, cc giao thc Mobile-IP v Ad-hoc nh DSR, TORA, DSDV v AODV. Cc agent truyn ti UDP, TCP. nh tuyn (routing) Lung packet (packet flow) M hnh mng (network topology) Cc ng dng Telnet, FPT, Ping. Cc packet tracing trn tt c cc link v trn cc link xc nh.3. Cc bc c bn trong m phng kch bn trong NS-23.1 Khi to v kt thcMt m phng bt u vi cu lnh: Set ns [new Simulator]y l dng lnh u tin trong tp lnh tcl. Dng ny khai bo mt bin mi dng lnh set. Dng bin ns c th s dng tt c cc phng thc ca lp Simulator. lu tr d liu m phng v hin th kt qu m phng chng ta to file bng cch s dng lnh open. # open the trace file Set tracefile1 [open out.tr.w] $ns trace-all $tracefile1 #open the NAM trace.file Set namfile [open out.nam w] $ns trace-all $namfile Kt thc chng trnh c thc hin bng mt th tc finish#Define a finish procedureProc finish {} { Global ns tracefile1 namfile $ns flush-trace Close $tracefile1 Close $namfile Exec nam out.nam & exit ()}Cui chng trnh ns chng ta s gi th tc finish v ch ra thi im kt thc. V d: $ns at 125.0 finishLnh trn c dng gi finish vo thi im 125 giy. Cui cng cho trnh m phng bt u bng lnh: $ns run3.2 nh ngha cc nt v mng lin ktu tin l qu trnh thit lp mng c bn. NS script bt u bng vic to ra mt instance cho i tng Simulator (i tng m phng). Set ns [new Simulator]: To instance ca Simulator, gn vo bin ns. Dng ny s thc hin. Khi to nh dng packet. To b lp lch (mc inh l Calendar scheduler B lp lch thi gian). i tng Simulator c cc hm thnh vin thc hin sau: To i tng gp nh cc node v cc link. Connect (ni) cc i tng thnh phn mng c to li vi nhau (v d nh hm attach-agent). Gn gi tr cho cc tham s cho cc i tng thnh phn mng (thng cho cc i tng ghp). To cc connection gia cc agent (v d nh to cc connection gia tcp v sink). Xc nh tuyn ty chn trnh din NAM. V.vHu ht cc hm thnh vin dng cho mc ch thit lp m phng (c cp n nh cc hm plumbing) v cho mc ch lp lch. Cc thc thi cho cc hm thnh vin ca i tng Simulator c nh v trong file ns-2/tcl/lib.ns-lib.tcl. $ns color fid color: gn mu cc packet cho lung c m nhn dng lung fid. Hm thnh vin ny ca i tng Simulator c dng cho vic m phng, v khng c tc dng g trn m phng thc t. $ns namtrace-all file-descriptor: Hm thnh vin ny yu cu m phng lu li cc du vt m phng vo trong nh dng u vo cho NAM. ng thi c th cung cp trn file m trace (du vt) s c ghi vo bng lnh $ns flush-trace. Tng t, hm thnh vin trace-all dng lu trace theo nh tuyn dng chung. Proc finish{}: c gi sau khi m phng kt thc. Trong hm ny cc tin trnh post-simulation (m phng thng bo c xc nh). Set n0 [$ns node]: hm thnh vin node khi to mt node trong NS l i tng ghp bao gm address (a ch) v post classifiers (b phn loi cng). User c th to node bng cc to ring i tng address v port classfier v ni chng li vi nhau. Tuy nhin cc hm thnh vin ca i tng Simulator thc hin vic ny rt n gin. $ns duplex-link node1 node2 bandwidth delay queue-type: to hai simplex link (lin kt n) vi bandwidth v delay xc nh tuyn, ni 2 node xc nh li vi nhau. Trong NS, hng i u ra ca node c thc thi nh mt phn ca link, v vy user nn xc nh lun queue-type khi khi to link. Ging nh node, link l i tng ghp, user c th to v ni cc link vi cc node. M ngun link c tm trong file ns-2/tcl/lib/ns-lib.tcl v ns-2/tcl/lib/ns-link.tcl. $ns queue-limit node1 node2 number: xc nh gii hn hng i ca hai simplex link kt ni node1 v node2 vi nhau. $ns duplex-link-op node1 node2 : dng cho NAM.Qu trnh tip theo thit lp cc agent nh TCP, UDP: cc ngun traffic nh FTP, CBR; connect cc agent vi cc node v connect cc ngun traffic vi cc agent. Set tcp [new Agent/TCP]: lnh to ra mt agent TCP, v y cng l cch to ra bt k agent hay ngun traffic no. Cc agent v cc traffic cha trong cc i tng c bn thc (khng phi trong cc i tng kp). Hu nh c thc thi trong C++ v c lin kt n OTcl. V vy, khng c hm thnh vin ca mt i tng Simulator xc nh l c th to ra cc instance ca cc i tng ny. to c agent v ngun lu lng th user cn phi bit tn lp ca i tng ny (Agent/TCP, Agent/TCPSink, Application/FTP v.v). $ns attach-agent node agent: hm thnh vin attach-agent gn agent vo node. Hm ny s gi hm thnh vin attach ca mt node xc nh tuyn, gn agent vo node . V vy, user c th lm tng t, nh $n0 attach $tcp chng hn. Ngoi ra, mt agent c th dng hm attach ca n gn mt ngun traffic vo chnh n. $ns connect agent agent2: hm thit lp lin kt lun l gia 2 agent, bng cch thit lp a ch ch n mng ca nhau v cp a ch cng.By gi gi s tt c cc cu hnh ca mng c thc hin. Tip theo l ghi kch bn m phng. i tng Simulator hin c nhiu hm thnh vin tp lch. $ns at time string: hm ny yu cu scheduler (b tp lch) lp lch cho String thc thi vo thi gian time. Trong NS, thc t th ngun traffic khng thc hin truyn d liu tht, nhng n li thng bo cho agent pha di rng n c d liu cn truyn. Khi agent s to ra packet truyn d liu y i.Cui cng l chy m phng bng lnh $ns run.Trong NS-2, mt mng my tnh bao gm cc node c ni vi nhau bi cc link. Cc event c lp lch truyn i dc theo cc link, ngha l truyn gia cc node. Agent c gn vo node to cc packet khc nhau (nh agent TCP hay agent UDP). Traffic source (ngun lu lng) chnh l application c gn vo agent.Kch bn OTcl cho lp lch s kin: To b lp lch, lp lch s kin. Khi ng b lch nh sau:Set ns [new Simulator]$ns at $ns run3.3 Khi to nodei tng m phng node c dng khi to mt node. Hai node c to vi iu kin n0, n1.Set n0 [$ns node]Set n1 [$ns node] to lin tc 5 node, ta dng cch sau:For {set i 0} {$i