Nghiên cứu mô hình hệ thống hội thảo đa điểm dựa trên giao thức ip multicast

CHUONG TRINH VUON UOM KHOA HOC - K? THUAT TRE oOo EDê tài NGHIEN Ceti- MO HINH ROI 'MAO DA DIEM DVA TREN GIAO THffC IP MULTICAST 4O is • Chu nhitn: Le Phu& L(ic Ca quan chü tri: Trung tam Phat trien Khoa hoc vã Ong ngh Tre Thanh Doan THANH PHO HO CHI MINH - THANG 03/2007 CHONG TRINH VON OM KHOA HOC - K? THUAT THE 000 Oe tai NGHIEN COI MO HINH HO' THAO DA DIEM DU'A TREN GIAO THeC IP MULTICAST Chu nh*n.: Le Phwfre LOc Co quan chu tri: Trung tam Phat tri6'n Khoa hoc va Cong ng4 Tre Thanh Doan THANH PHO HO CHI MINH - THANG 03/2007 Nghien ctiyt mo hinh hOi thao da diem dira tren giao thtiv IP Multicast PHAN I: TONG QUAN VE DE TAI Thong tin ye de tai 1.1 Ten de tai 1.2 Chit nhiem 1.3 Ca quan chit tri de tai NOi dung de tai 2.1 Muc tieu de tai 2.2 Tong quan tinh hinh nghien dru 2.2.1 Ngoai mrac 2.2.2 Trong ntrac 2.3 NOi dung nghien ciru PHAN II: GIOI THIEU HOT THAO TRUYEN HINH Cac giai phap hOi thao truyen hinh qua mang IP Multicast flOi thao truyen hinh qua IP Multicast MOt so pi-Ian mem nghien dru va thtrang mai PHAN III: PHAN TICH CONG NGHE Phan tich cong nghe IP Multicast 1.1 LAI va nhtrcyc diem dm IP Multicast 1.2 Cac giao thirc multicast 1.2.1 Giao thirc dense-mode 1.2.2 Giao thirc sparse-mode 1.3 Giao thirc Binh tuyen multicast 1.3.1 DVMRP 1.3.2 MOSPF 1.3.3 PIM-DM 1.3.4 PIM-SM 1.3.5 CBT 1.3.6 PIM Sparse-Dense mode 1.3.7 Tam tat 1.4 Chuyen mach multicast b lOp 1.4.1 CGMP 1.4.2 IGMP Snooping Phan tich cac ky thuat truyen video qua mang 2.1 Mang chuyen mach 2.2 Mang chuyen goi Phan tich cac kSithuat kiem soat tac mang 3.1 Kiem sok tac dOi vOi goi da lieu video 3.2 Thich nghi vai tic 3.3 Cac dich vu tich hop 3.4 Kiem sok tic multicast 3.5 Dieu chinh bang thong c6 six ht; tra mang Chiron Mid: Vtron won Khoa hpc - Ky rho: Tre 5 5 5 5 8 10 16 22 29 29 30 32 32 33 33 34 34 35 36 37 38 38 38 39 39 40 41 41 42 42 44 45 47 50 Nghien ciru nio hinh h(fi da Wins dira tren giao thtiv IP Multicast 3.6 Phuang phap dieu chinh theo noi nhlan 3.7 Tom tat ICy" thuat nen video phan lop 4.1 DCT phan 16p 4.2 Ma h6a Pyramid 4.3 Ma hoa ,anh Subband Phan tich kien truc irng dung h6i than da diem 5.1 Internet Protocol 5.2 IP Multicast 5.2.1 Duy tri nh6m 5.2.2 Tam vkrc multicast 5.3 Dinh tuyL 5.4 Lightweight Session 5.4.1 Real-time Transport Protocol 5.5 Cac nh6m multicast 5.6 Packet scheduling 5.6.1 Random drop 5.6.2 Priority drop 5.6.3 Random Early Detection 5.6.4 D6,cong bang Kiem soat tac mang multicast 6.1 Multicast phan lop 6.2 Dieu khien tac PHAN IV: MO HINH HOT THAO DA DIEM Pham vi 1.1 Yeti cau ve may tram 1.2 Yeu cau ve thiet bi mang Sado mang 2.1 M6 hinh tren LAN 2.2 M6 hinh tren WAN 2.3 M6 hinh tren Internet Hog dOng cua phan mem 3.1 Sa (16 hog &Ong 3.2 Th6ng s6 dau vao Giao thirc 4.1 Truyen van video / audio 4.2 Quan ly nhorn 4.2.1 Dinh dang g6i thong bao 4.2.2 Lay thong tin tir Session Directory Server 4.2.3 Tham gia session 4.2.4 Tao session moi Chwang hinh Virern won Khoa h9c - K9 thulit Tre 52 53 54 54 57 58 61 61 62 63 65 66 67 68 70 71 71 71 73 73 74 74 76 79 79 79 80 81 81 82 83 83 83 84 86 87 89 89 90 91 91 Nghien cern nno hinh h3i Mao da thra den giao that IP 'Mideast 4.2.5 Ryi session 4.3 Kie'm soot tac 4.3.1 Qua trinh trac luong \fa dieu chinh 4.3.2 Toc dO giri dm 16p Thir nghiem va danh gia 5.1.1 MO hinh thir nghiem 5.1.2 Cong cu thin nghiem 5.1.3 Ket qua Ket lua'n PFIAN V: PHV LUC Phan mem mo ph6ng ns-2 Huong dan cai dat ns-2 tren Linux 2.1 ChuAn bi 2.2 Cai Tat Tcl 2.3 Cai d4t Tk 2.4 Cai dat OTcI 2.5 Cai dot Tc1CL 2.6 Cai dot ns 2.7 Cai dot xgraph 2.8 Cai dlat nam 2.9 Da't1Din mOi twang shell Huong dan thuc hien mo ph6ng 3.1 Truarng hop &mg RLM 3.2 Twang hop dimg Packet Pair Cis:rang trinh Vrrirn irons Khoa ItQc - Ky thut:it Tre 92 92 92 96 97 97 98 98 100 101 101 101 101 102 102 102 103 103 103 103 104 104 105 105 Nghien can mo lank hQi thdo da (Vim thra tren giao thirc IP Multicast PHAN I: TONG QUAN VE BE TAI Thong tin vt de tai 1.1 Ten a tai Nghien ciru mo hinh hoi thdo da diem dtra tren giao thirc IP Multicast 1.2 Chi' nhiem KS Le Phuac LOc(Phan vien CNTT tai TPHCM) 1.3 Cu quan chu tri de tai Trung tam Phat triL Khoa hoc va Cong nghe Tre Thanh Doan TPHCM NOi dung 6' tai 2.1 Muc tieu de tai Nghien ciru cong nghe Video conferencing da die'm qua mpg IP Multicast, danh gia cac huang tiep can va phan tich nhung mat you, mat manh cua cong nghe so vai nhung cons nghe da co Tir de m6 hinh phu h9p va kiem nghiem 14i de co the tien hanh hien thirc mo hinh twang lai 2.2 'Ding quan tinh hinh nghien 2.2.1 Ngoai nuxiv ,Cong nghe Video conferencing da" dugc va Oat triL m4nh me a khap nai ten the giai 20 ram hulk day, Video conferencing da doi tren m4ng ISDN cong vai tieu chuan di kern la H.320 Hiep,hOi Vien thOng Quoc to (ITU) quy dinh Sau to chirc ITU phat trien mOt so 119 chuan khac nhu H.324 tren mpg dien thoai PSTN, H.323 teen mpg IP, Ngay vai xu huang hOi to tren nen IP (IP convergence), cac dich vu Chuong trinh nrow tram Khoa hpc - Ky thit01 Tre Nghien caw mo thao da diem dira tren giao fin& IP Multicast data, voice, multimedia ducfc trien khai teen mot ca sa tang thiing nhAt, xuyen suot la mang IP Chuan H.323 tra nen dirge phi) bien rOng rai vai hang log cac san pham phan mem thuang mai, phan cong chuyen dung dugc thiet ke de ch4y vai chuAn H.323 Tuy nhien, vai mat d6 sir dung throng truyen mang IP hien nay, viec sir dung hieu qua bang thong la van de quan hang dau, dac b* la vai cac ung dung tieu ton nhieu bang thong duarng truyen nhu Video conferencing, Video broadcast Cac giai phap Video conferencing da diem dung chuan H.323 bien hien truyen nhan du lieu theo phucmg phap unicast th6ng qua mgt MCU (phan mem hoac thiet bi chuyen dung) MCU co vai tro nhan hinh anh, am tir tat ca cac dia diem girl den, sau, dO trOn chiing 14i va phan phoi m8i ban copy den tong dia diem Chang han mgt cu6c hOi thao \Teri dia diem, m8i dia diem can giri di khoang 80Kbps du lieu (16Kbps voice va 64Kbps video) thi MCU phai giri ye dia diem lai hinh anh, am cua Ca dia diem Nhu vay tong cong bang thong duarng truyen can thiet la x x 80 = 2,4Mbps Cong nghe IP Multicast duqc ap dung vao ky thuat Video conferencing tren mang IP de giai quyet van de hao phi bang thong duong truyen Dan cu twang hcrp Video conferencing gifra dia diem de cap & tren, thay vi giri ban copy den diem 14i nhu H.323 Unicast, IP Multicast chi can giri,m0t ban copy di qua tat ca node, d6 dung lucmg duarng truyen can thiet chi la 480Kbps Ky thuat Video conferencing / IP Multicast hien van giai doan phat trien So lucmg cac sin pham Video conferencing / IP Multicast hien chi dem tren,dau ngon tay, chua phong phu va day du chiral loci nhu cac san pham chuan H.323 va H.320 Vi vay viec nghien ciru de dp dung cong nghe Video conferencing ten IP Multicast la rat can thiet 2.2.2 Trong intim Han het cac san phAm truyen hinh,,h0i thao qua mang Bang sir dung nuac deu la nhung san pham phan mem va phan cong cua nuac ngoai Cac dich vg truyen hinh h6i nghi (Video conferencing) bien hien nuac deu dung cong nghe H.320 tren duarng truyen ISDN — day la chuan cong nghe Video conferencing cu duac dung nhieu qua khir Hien mgt so nai da trang bi he thong Video conferencing sir dung cong nghe H.323 mai qua mang Internet Chuan H.323 hiO,dang la chuan Video conferencing dung nhat ten the giai c6 the sir dung qua mang LAN, WAN va Internet Tuy nhien, cong nghe Video conferencing qua mang IP Multicast hau nhu van chua c6 nai nao nuac trien khai Chuong trinh Vtrow from Khoa hoc - K9 thu(itTre Nghien criu m8 hinh hQi Mao da diim dva tren giao thik IP Multicast va nghien cau Sap,tth day, ding nghe IP, Multicast duqc chuAn hoa ten the giai va trien khai r6ng rai, viec chuan bi tir bay giey cho nghien ciru va img dung tren IP Multicast la rat can thiet 2.3 Ni dung nghien ctiu Cac nOi dung can nghien cfru pham vi de tai bao g6m: Khao sat cac san phAm phAn mem, phAn cirng chuyen dprw (16112 ky thuat Video conferencing, bao gOm cac giai phap unicast \ multicast ten the giai Danh gia cac san phAm Video conferecing dien hinh de neu b4t uu diem dm giai phap Video conferencing da diem qua IP Multicast ding nhu nhting troy ngai cua no Tir de xuAt mo hinh va pham vi ap dung thich hcrp Nghien ciru cac giai phap nen tin hieu hinh anh va am duce dung ky thOt Video conferencing de ap dung vao mo hinh Video conferencing se de xuat Nghien ciru ding nghe IP Multicast va phtrcrng an trien khai IP Multicast ten he thong mang, IP th6ng thuong, d6 tim giai phap Irian dung giao thirc IP Multicast de truyen tin hieu Mill anh / am da dugc nen Mo phOng va tit* nghiem mo hinh da de xuAt de chimg to dO hieu qua Chwing (rink nob? tram Khou hoc - KC thwit Tre Nghien ctiu mo hinh hQi thdo da aint dy.a tren giao thti.c IP Multicast PHAN II: GO' THIEU HOI THAO TRUYEN HiNH Cac giai phap hoi thao truye'n hinh qua mang , Da tir lau, cac dich vu thong tin dai chiing nhu phat thanh, vo tuyen truyen hinh &rex tai tren song ,mang va truyen qua cac tram phat song di khap nai tren the giori Cho den horn nay, ky thuat truyen thanh, truyen hinh dung tin hieu tuong tir da dat den d6 hoar' chinh va 016 bien Ong rai Ciing chinh luc do, cong nghe ky thuat so ding ca son tang vien th6ng cho no da khai sinh va phat trien manh me Nhieu loai he thong mpg dai nhu ATM, ISDN, va gan day nhat la mang Internet Ky thuat truyen thanh, truyen hinh cid nhanh chong buoc sang link vuc ky thuat so vai by \tong dOi mai ye chat luang, ma Ong dich vu va tiet kiem chi phi Ke tir khai niem truyen thanh, truyen hinh ky thuat so qua mang may tinh - goi • tat la truyen hinh qua mang - Thai kS, dAu dung WIT cac kenh vien thong han the nen chua trien khai ducfc truyen thanh, truyen hinh vi day la nhing loai du lieu kich thuac Ian Cong nghe bang thong r6ng va cac ky- thuat nen dir lieu hinh anh (Video) va am (Audio) da thiic day ky thuat truyen hinh qua mpg M6t boat dich vu truyen thong da pluxong tien (multimedia) qua mpg xuat hien nhu Internet Phone, Picture Phone, Video / Audio Broadcast, Video on Demand, Video Conferencing, Distant Learning, Online Show, Neu nhu tnrac ky thuat vo tuyen truyen hinh chi mang tinh mot chieu - tirc hinh anh va am chi &roc truyen tir dai phat den may thu hinh, gia day ky thuat h6i thao tin xa Video Conferencing cho phep Ca hai ben giri tin hieu hinh anh va am cho Video Conferencing cang &rye sir dung rOng rai tren the giai nhang nam gan day Day la thuat ngrr chi viec to chirc cac cu6c h6i hop tir xa qua he thong vien thong nhu mang may tinh, &rang dien thoai, duang truyen so lieu Hinh anh va am thanh, tieng not cua cac ben h6i hop se &Jac truyen hinh, truyen tr%rc tiep cho qua he thong vien thong CO the xem Video Conferencing nhu mot cau truyen hinh da chieu qua mang Vao thai ky du, Video Conferencing yeu dugc khai thac ten cac loai mang chuyen dung de truyen,da lieu multimedia nhu ISDN Tuy nhien sau ISDN dan dan it pho, bien va ninemg cho sir phat trien cua mang IP - ca soy tang chit yeu cua Internet Ky thuat Video Conferencing Chuang &Mit Vtrow worn Khoa hpc - Ky thuOt Tre Nghien cfru mo hinh hOi Mao da tam dva tren giao fink IP Multicast cling theo d6 di cu qua he thong mpg IP, ved sir d6i cita chuAn H.323 H.323 la chuAn to chirc quoc to ITU de xtrong, dimg cho cac he thong Video Conferencing tren mpg IP Twee kia, ITU cling da ban hanh m6t s6 chuan Video Conferencing ten cac loai mpg khac, vi du H.320 dung tren ISDN, H.324 dimg cho mang dien thoai ding Ong PSTN Co sa ky thuat de truy6n tai tin hieu video / audio ten mang IP la giao thirc RTP (Real-Time Protocol) Cac goi du lieu RTP truyen ten mang chira nhang tin hieu video / audio da &roc nen theo mot cac chuan dinh trtrac Nal nhan cac goi RTP se can cir vao d6 de giai ma RTP va giai nen du lieu hinh anh, am Tin hieu hinh anh / am la nhang du lieu doi h6i tinh th6i gian thuc, co nghia la dam bao nai nhan phai nhan dugc du lieu can thiet mot khoang th6i gian xac dinh Chang han nhu vai dir lieu am thanh, tieng not se bi ngat quang neu cac g6i audio den cham han du kien Giao thirc RTP duce hiep hOi IETF (Internet Engineering Task Force) phat trien de h6 trg truyen cac goi IP theo th6i gian thuc Tren cac thiet bi mang, cac g6i RTP se dugc tru tien luu thong han so vai nhang g6i du lieu IP kh6ng can tinh th6i gian thuc nhu E-mail, WWW: Giao thirc RTP cung cap dich vu truyen tai (10' lieu multimedia va dugc ho tro b6i cac giao thirc dam bao chat luting dich vu (QoS) cai dat san tren nhieu he dieu hanh va thiet bi mpg RTP thuong nam tang session trong, m6 hinh mang OSI, cai dat d6c lap doi vai cac lap mang ben dual Hau het cac (mg dung truyen hinh tren mang IP deu sir dung RTP ten tang UDP (User Datagram Protocol) de truyen tai du lieu video / audio Viec cai dat RTP tren tang TCP khong hieu qua va ding khong co nghia co che retransmission oh TCP kh6ng the hien tinh th6i gian thuc Chun H.323 dm ITU cho Video Conferencing dung RTP de truytn tin hieu video / audio Chub duge phat trien tir,nam 1996, hien da kha hoan chinh va dang thinh hanh khap nai Cho den nhieu phan mem cling nhu nhang thiet IA Video Conferencing chuyen dung da ho trg chuan giao tiep Ngoai viec sir dung RTP de truyen van tin hieu dieu khien va dir lieu video / audio, chufin 11.323 dinh cac giao thirc khac ho trg cho viec trien khai Video Conferencing ten cac mang IP thuc te Cac giao thirc Ito trg nhimg tinh nang nhu thiet,lap cuOc goi, kiem soat kenh truyen, MCU, Gatekeeper, Gateway, z Thiet bi MCU (Multipoint Control Unit) la loai thiet, dung de dieu phoi mOt cuOc h6i thao Video Conferencing da diem, tire cho phep nhieu nguai tham gia va giri tin hieu hinh anh / tieng not dong th6i cho Cac diem tham gia h'Oi thao girl tin hieu video / audio cho MCU, MCU sau dO trOn tin hieu video / audio nhan dtrge va phan phoi lai cho cac diem tham gia Gatekeeper c6 chin nang Chuang trinh Virden tram Khoa hpc - Ity thuOt Tre Nghien caw nto hinh hQi Mao da diltn (Iva tren giao thti.c IP Multicast I I III ED Ilerf.e.te ■ O Hinh 33: Mei hinh chin clam bang thong vai packet pair Trong Hinh 33, Senderl gUi packet pair (PP) g6m hai gOi di lien den Receiver2, di qua doan Bottleneck Link, khoang each thai gian giira gOi se tang len ti le vOi bang thong dm doan Bottleneck Link Gia that packet pair chia hai loai: RBPP (Receiver Based Packet Pair) ya SBPP (Sender Based Packet Pair) Phuang phap RBPP thirc hien tinh toan tai diem nhan nen darn bao phan anh kip thed tinh trang &rang truyen, SBPP tinh toan tai diem giri sau nhan dirge phan hoi ACK to diem nhan nen thong tin cham tre han va khong dam bao luon nhan dugc ACK mang xay tac Ngoai dung lugng duerng truyen tai diem giri cho dir lieu di khac vai dung Luang cho dir lieu ye ding la mot van de voi SBPP Phuang phap RBPP cho phdp diem nhan phat hien the truac hang dgi o doan bottleneck bat dau hinh ya kha lau truck hang dgi day Ca so de Oat hien tac la bang thong uac Luang thap han toe dO nguon phat Dau hieu nhan biet la luc PP dau tien red, hang dgi sau xay tac DO tre to Luc tac tai bottleneck,den diem nhan phan irng la khoang died gian PP di tir bottleneck den ,diem nhan Phuang phap packet pair khong ,dung dau, hieu mat gOi d trac uting bang thong nhu cac phuang phap dieu khien tac khac Vil v4y phuang phap dam bao hieu suat truyen dt lieu, ea tren nhang throng truyen hay mat goi nhu wireless Tuy nhien phuang phap packet pair ding co mot s6 mat han che Thd nhat la str phu thuOc vac) ill-1h chat vat ly cua he thOng mang Vi du packet pair chay tren he thong c6 can bang tai (load balancing) vi ket qua tinh toan bang th6ng se tr& nen vo nghia cac gOi di lieu di theo cac huong khac mot each ngh nhien Mat thir hai la ,dO nhay cua phuang phap packet pair nen tip dung cho thong truyen tai dir lieu c6 luu luting dao Ong thuang xuyen khien ket qua du doan dia packet Clurong trinh Vtrow growl Khoa h9c - Ky thu(it Tre 93 Nghien caw me With hQi thdo da diem thra tren giao thuc IP Multicast pair cling dao d6ng‘ lien tuc Khi cac giao thirc dieu khien t&c phai co co the loc ket qua cila packet pair mot cach thIch hop Phuang phap dieu khien tac dua tren RBPP &roc thuc hien nhu sau Nguon Oat giri du lieu theo cac packet pair qua tat ca cac lap, dua tren ca che phan phoi fair scheduler.s Truac nh4n du lieu, cac diem nhan xac dinh bang thong dm m8i lop bang th6ng tin tir cac session thong bao cac ngu6n Oat quang IA len mang Goi PPt la bang thong tinh duoc tir packet pair tai thai diem t, va Bn la bang thong hien tai cua n lap: Bn = Zni=l Li , lap i truyen du lieu vai bang thong la Li Goi Be la tong bang thong LT& luting Khi b'at Au session, diem nhan tham gia vao lap co sa (base layer) va doi packet pair dau tien giri den Neu sau mot khoang thai gian timeout dinh truac, diem nh4n van khong nhan duvc packet nao thi có nghia la no khong du bang thong de nh4n lap co sa Neu diem nhan duvc packet pair dau tien vao thai diem t, diem nhan se gan, gia tri thai gian kiem thir Tc = t + C, dO C la thai gian chu kS7 kiem thir Vao moi alai diem Tc, diem nhan se kiem tra de them va bat lap Duai day la giai thuat thuc hien diem nh4n nh4n duvc mot packet pair tai thai diem ti: if PPti < Bn then /* bo belt lop */ - Tc = t + C - until Bn < PPti (1) * drop layer n * n := n -1 elseif PPti Bn and then Tc < ti /* nhan du'Oc cac PP It nhal C thin vi theri gian */ then /* them lap */ - Be := Tc — C < i < ti PPi /* ray gia tri bang thong t61 thigu u'ac lu'dng clu'Oc */ - Tc = t + C - if Be > Bn then while Bn+1 < Be (2) * add layer n + * n := n +1 Clurong trinh ['iron from Khoa /19c - K9 thuezt Tre 94 Nghien art' mo hinh lrgi Mao da diem &fa tree giao thfre IP JVItaticast Tom lai, mOt lap bi b6 bat c6 mOt gia tri PPi nhe han tong ltru Itrong cac lap hien co Bn , lop dugc them vao tit)/ theo gia tri PPi toi thieu nhan dugc chu ky C (tire tat ca PPi > Bn chu kjr nay) Trong tnrong hop tic xuAt hien nhiau (long art lieu mai khoang thi gian nhO han chu ky C, dO packet pair se khong the truyen duce den diem nhan Vi vay can c6 mOt ca the de giarn tic truong hap Neu diem nhan khong nhan duce packet nao sau mOt khoang thOi gian timeout dinh truac thi no se be bat lap; nau lOp la lap ca sa thi se (king session., Trang thai mat g6i dugc theo d''i qua so trinh tar packet, packet dau tien dugc danh dau bang mOt tru?mg bit Nhu vay m'ol packet chira mOt layer id, so trinh tu, va tnrOng bit Neu diem nhan dugc mOt so packet nhung khong co PP thi no se It& hrong ti la mat goi va be bat lap neu ti le vugt qua ngtrong dinh truac (thuOng la 10%) Sau diem nhan dqi them mOt khoang thtfi gian blind truac tinh lai ti le mat goi Chu kS, blind gulp cac diem nhan khong phan ling thai qua truac tinh tang mat ed Khi mOt diem nhan tham gia vao mOt lap, tat ca cac diem nhan khac qua ding mOt bottleneck cling can tham gia vao lap d6 de tranh vi'e'c lang phi bang thong Khi mOt diem nhan b6 bat lap xay tic nghen, tat ea cac diem nhan khac qua ding mOt bottleneck cling phai 136 lap thi mai het tic Qua trinh goi la (long 130 tham gia hoac rai khoi lap khoi lap dugc thue hien nh6 vao PP, tat ca cac diem Vic dong b0 nhan deu ding lac nhan duce cling mOt PP Vic (long 130 them lap khO khan han cac diem nhan khong kill% Ong ding lac nen thOi gian Tc cua chimg khong dong 130 va tham gia vao lap nhung thisi diem khac Khi dO cac diem nhan tham gia tre kh8ng dugc 'Tong b0 truac cac diem nhan truac da dat den toe dO t6i uu Tuy nhien diau chi xay mOt Ian dau, vi sau Ian be lap dau tien (do PPt < Bn) thi thoi gian Tc cua tat ca cac diem nhan se dong b0 va chang ce the tham gia lap ding lite MOt van de khac ma phuong phap packet pair gap phai, la sy dap fin cham IGMP cac diem nhan raj 16p IGMP co the mat,den vai giay de cat (prune) nhom multicast lap CO mOt so icy thu4t de du doan de co the roi nhom nhanh, nhien viac dtmg 130 rOi lap phuong phap packet pair giup lam nhe anh cua dO tre IGMP Phuang phap diau khian tic packet pair not tren giup theo &Si tinh trang bang thong ,ma khong can dung each gay mat g6i nhu cac phuong phap truyan thong Day la ky- thuat don gian va hiau qua da tham gia dung vao cac lap van dam bao tinh Ondinh, , ding bang, manh me, linh Ong can co mOt giao thirc dieu khian CIF:rang um,: Kiwi: hoc - ihutit Tre 95 Nghien caw nto hittlt h(ii than da diem diva tren giao thtiv IP Multicast 4.3.2 'Vic cho girl ciia lcrp HiEn nay, phan Ian irng dung yeti cAu bang th6ng cao ten mang multicast la cac trig dung truyEn hinh da diEm nhu video conferencing, video broadcast Trong clang dir liEu video chiEm ti cao nhat nen can tip dung 1(57 thuat phan lop va diEu khien Lac de darn bao chat luting hinh anh triEn khai tren mai twang mang di chung Van dE phan lop tin hiEu video nen cac lop co sa va lop tang cuang da &roc thkrc hiEn qua cac giai thuat ma h6a phan lap (chang han PVH, H.264) Cac giai thuat cho phdp tit), biEn so luting lap va bang thong eita timg lap de thuan tin cho cac irng dung có the hp chon toc dO clang dix liEu giri thich hop cho cac nhOrn diem nhan tren mpg De tan dung bang thong &rang truyEn hiEu qua, ngu8n phat phai phan phoi cac lap vao cac nhanh multicast cho tat ca cac diem nhan deu dung het luting bang thong bottleneck dm chung Nhtx vay van de dat cho nguon, phat la diEu chinh so luting va bang thong m8i lap de luon có the chon mot to hop lap (gam lap co sa va cac lop tang cuang lien tiep) có tong t6c dO pha hop vai bang thong da biet cua mot ,diem nhan Day la phuong phap multicast phan lap có sv diet' chinh toc ngu6n phat (sender-adaptive) Phtrong phap yeu cAu cac diem nhan dinh kS, bao cao tinh tang bang thong ctia mink cho nguon phat thong qua cac th6ng dip h6i dap Dkra vao ngu6n phat tip dung cac giai thuat nhu dynamic programming, divide and conquer, de dinh t6c dO tai tru cho m8i va to hop lap can thiet cho m8i diem nhan Phtrong Oar) diEu chinh the dO ngu8n phat ap dung hiEu qua cho cac irng dung multicast tong quat not chung Tuy nhiEn phuong phap lai tie!) tuc sir dung co the h6i dap, mau thuan vai y Wang ban dau cua ky thuat han chE tac ma chung tai de nghi Vi the can tim mot giai phap thich hop dE multicast phan lop vira han the tac nghen, vira linh Ong diet' chinh phit hop vai dieu kin thvc te PhAn Ian cac irng dung multicast phan lap la video broadcast, video conferencing da diem Trong dO dir liEu chiem bang th6ng cao va de xay tac la d6ng video Ky thuat multicast phan lap chit you la ap dung cho tin hiEu video de nguai xem quan sat dtroc hinh anh tot va on dinh nhat Ky thuat dieu chinh bang thong lap video hiEn deu thkrc hiEn bang cach tang giam thong so luting tir Ma qua trinh nen Thong so luting tir ltha la nhan to quan nhat the hiEn chat luting hinh anh eita clang video Voi sit cam nhan eita nguai xem, six cai thin yes chat luting hinh anh chi nhan bi'et duoc co sir thay doi rEt ve hE so luting tir ft& Hay nOi each khac, hinh anh chi co chat luting tot han doi vai nguai Chuang trinh Vtrern tram Khoo h9c - Ky thuOt Tre 96 Nghien ctiu mb hink hoi dodo da dam 'dim fret: giao Mirc IP Multicast xem n6u t6c d6 (long video c6 sir thay dOi ro ret VI ld d6, ta khong can thiet phai chon toe d6, dong video vita khit vai bang thong dinh tnrac (dm diem nhan) ma co the chon theo m6t b6i so cho gan vai bang thong dinh tnrac , Theo cach tren, ta co thd chia don video mot lap co so., va cac lap tang cuang deu bang nhieu lap tang ctrang Trong da toc d6 va bang vai m6t gia tri an dinh nhtr 32 Kbps, 64Kbps, 128Kbps Do biet mt.& toe dO cua mei 16p nen m6i diem nhan CO the chit dOng quyet (firth them hay bat bao nhieu lap thy theo bang thong hidn tai cua mirth Qua d6 ta,tranh &roc vidc‘sinh dong thong dip hoi dap khong can thiet, han che toi da kha nang tac nghdn, nhtmg van c6 the chi' dOng dieu chinh toe d6 nhan de sir citing &rang truyen co hidu qua Thir nghiem va danh gia Doi vai hOi thao truy6n hinh da diem, van de tiet kidm bang thong va darn bao chAt luting hinh anti am la clang luu 3", nhAt Trong dO tinh chAt tiet kidm bang thong la tru diem chung cua cac (mg ,dpng tren IP Multicast so vai cac (king IP Unicast thong thuang., Phan quan tong can danh gia dm m6 hinh la tinh kha thi giai phap kiem sok tac nharn dam bao toe dO truyen clang du lidu hinh va tieng luon &roc on dinh, tir d6 dam bao chAt luting hinh anh va am ma m81 ngtrai &mg nhan dirge 5.1.1 M8 hinh thii nghiem Chimg ton da tin hanh m6 ph6ng va thir nghidm he thOng M6 hinh mpg &roc thi6t lap nhu sau: 256Kb 1Mb 56Kb 128Kb flan da 64Kb (1An sau 25 OKb 64Kb Hinh 34: 10Mb So coo mgng mo phong Chtrong ifinh Virent from Khoa hoc - KJ' thili)t Tre 97 Nghien trio mo hinh hfii thdo da dam dva tren giao du& IP Multicast He th6ng mang c6 node voi ngu6n phat S, diem nh4'n R1, R2, R3, R4 va node routing N1, N2, N3 Dong, da lieu la loci CBR truyen van bang giao thirc UDP, lap, co' toc d6 32Kb va cac lop tang twang, moi lop co toe d6 32Kb Chieu dai packet la 1KB, hang doi kieu DropTail c6 kith thu6c 15 Giao thirc dinh tuyen multicast la DM voi thoi gian prune timeout la giay Chung toi tien hanh thir nghiem vdi hai giao thirc RLM va Packet pair vai cong so lieu dau vao neu tren 5.1.2 Cong cu thir nghiem ChUng toi tier' hanh mo ph6ng he th6ng neu ten tren phan mem mo phong NS-2, a-14y tren he dieu hanh Linux Day la 'than mem chuyen dung cho viec m6 phong cac giao thirc mang sau thiet ke, &me nhieu nha nghien ciru tin dUng de danh gia cac cong trinh nghien ecru m6i linh cong nghe truyen thong Thong tin tau hinh may tinh dimg thir nghiem: CPU Pentium 3.0Ghz, 512MB RAM He di'eu hanh: Linux Fedora Core (vai moi tn.r6ng hoa X, compiler gcc-3.4.2) PhAn mem mo phong: ns-2.29 va cac phAn mem di kern: o ve so d6 mang mo ph6ng: xgraph-12.1 o Xem 14i hinh anh Ong cua mang m6 phOng: nam-1.11 o Leap trinh Tcl: tcl-8.4.5 o Thu vien d6 hoa cho Tcl: tk-8.4.5 o Leap trinh Tcl huang d6i twang: otcl-1.11 o Leap trinh Tcl voi C/C++ (Tc1CL): tcicl-1.17 5.1.3 lat qua Tr4ng thai mat gOi qua trinh chay m6 phong throv ghi nhean bieu dtrai day vai twang hop bang thong Ni —> N2 la 128Kb (bieu d6 ben trap va 64Kb (Neu d6 ben phai) Chuang trinh neon :ram Khoa hoc - K9 thrult Tre 98 Nghien caw Ina hiniz hfii thao da Mem dva tren giao thav IP Multicast —RLM i—s—Packet pair ce 100 200 300 600 400 1000 700 1100 1200 1300 Th44 gian (ms) • —RLM * Packet pair 100 200 300 400 500 600 700 900 1000 1100 1200 1300 Thoi gian (ms) Hinh 35: So lieu mat g6i cna hat phuang phap vOi bottleneck la 128Kb vet 64Kb K'et qua thir nghiem cho thAy ca hai phucmg phap RLM va Packet pair deu diling 100% bang th6ng ctla clop bottleneck Ni -> N2 Tuy nhien ti le mat g6i cua RLM cang tang bang th6ng bottleneck cang gsiam Trong dO ti mat gOi dm Packet pair ca hai tnramg hop deu la 0% Chuang 'filth Virent tram Khoa hoc - Ify tint& Tre 99 Nghien cti.0 mo hinh thtio da tlidm d(ra tren giao Mk IP Multicast Ke't 1u4n , Chung toi da xuAt mot m6 hinh h6i than da diem v6i cac uu diem ve tinh tien, dung, yeu cau duping truyen khiem ton va chi thap tan dung he th6ng may PC va &rang truyen IP san c6 de trien khai cac cu6c h6i did° da diem v6i so luting lan nguai dung So v6i cac m6 hinh da trien khai tai Viet Nam gan day nhu h6i thao qua ISDN hay mai han nira la cac thiet bi H.323, mo hinh kh6ng can dau to them nhang thir nhu &rang truyen ISDN hay cac thiet bi / ,may chu lam elide nang MCU dat ,tien di kern vai giai phap H.323, da diem Van de kh6 khan viec trien khai m6 hinh la viec thuyet phuc cac nha quan co s6 tang mang quan tarn den viec trien khai IP Multicast ten ,cac thiet bi dinh tuyen cua ho Hien multicast dtrac ho try tren hau het cac b6 dinh tuyen nhu Nortel, Cisco (hoac co the dung mot may ,chu binh thuong chay trinh mroute de lam b6 dinh tuyen) nen chi phi thiet bi de trien ,khai khong la van de lan Tuy nhien trien khai ngu6i quan tri can thiet lap them cac chinh sach ve quan V, chat luting dich vu cho &mg &I lieu multicast nhu da trinh bay phan phan tich Giai guy& tac la mot , nhang bai toan phirc tap cua multicast phan 16p Phuang phap truyen thong la thiet lap mot giao thti.c de cac ben tham gia trao dpi thong tin trang thai cua Tuy nhien bien phap lai to kh6ng hieu qua chinh cac du lieu ding g6p phan gay tac Phuang phap chan doan bang th6ng qua cac packet pair giri chung (long du lieu giUp chan doan chinh xac kha nang du6ng truyen tai mai diem nhan ma khong can 1)6 sung cac phan tir dac biet tren mang hay chiem dung bang th6ng mang cho tin hieu dieu khien Chung toi da trinh bay giai phap multicast phan lop alp dung ksi thuat packet pair ket hop voi viec chia deu toe dO gii clir lieu, cho moi lap video tang man& Giai phap khong can dung thong tin h6i dap ma van dam bao cac ben tham gia c6 the truyen nhan tin hieu video co chat luting phU hop Chung toi da thkrc hien m6 phong he thong de kiem nghiem kha nang han the tac cua no so vai phuang phap RLM truyen thong va da thu dirge ket qua kha quan, the hien duac tinh on dinh can thiet ma ngtr6i xem mong muon Qua dO cho thay tinh hieu qua dm phtrang phap ap dung cho cac img dung video broadcast, teleconferencing da diem mai tnrong mang tich hop hien Chtratig trinh Vtran tram Khoa h9c - icy thuljt Tre 00 Nghien can mo hinh hOi thtio da diem dica tren giao them IP Multicast PHAN V: PHU LUC PhAn mem mo phong ns-2 Ns (network simulator) la mot phAn mem gia lap six kien r6i rac, chuyen dung de nghien ciru ve mang Ns cung cap kha nang ho trg mo phOng TCP, dinh tuyen va cac giao thirc multicast qua he thOng mang c6 day va khong day (n6i b6 va ve tinh) Ns ban dAu la mot phien ban cua REAL network simulator viet vao nam 1989 va dugc phat trien lien tuc sau d6 Vao nam 1995 vie‘c phat trien ns dugc h6 trg bai DARPA thong qua du an VINT tai LBL, Xerox PARC, UCB, va USC/ISI Hien viec phat trien ns dugc ho trq qua DARPA voi SAMAN va qua NSF vai CONSER, ca hai ding cong tac voi nhieu nha nghien ciru khac bao gom ca ACIRI Ns lam luon bao gom nhang dOng gop quan tir nhUng nha nghien ciru khac, bao Om wireless code caa cac du an cua UCB Daedelus, CMU Monarch va Sun Microsystems Htreeng dAn cai chat ns-2 tren Linux DAu tier' can cai dat m6i tru6ng lap trinh ng6n ngir Tcl/Tk va cac bin the dm Tcl nfar OTcl, Tc1CL Ns-2 dugc viet bang nein ngir ket hop C/C++ cho cac doan ma dOi hoi su tinh toan loin Ngodi cac script mo phOng cho ns-2 deu dugc viet bang ngon ngir Tcl Sau dO cai dat phAn mem ns-2 va cac cong cu 116 trg xgraph, nam (network animation) de ye sa minh hoat bang anh d6ng, mo to hoat &Ong dm he thong mang gia lap 2.1 ChuAn hi Moi tru6ng Linux can co g6i d6 hoa X Window, trinh bien dich gcc3.2 hoac cao hon Giai nen cac file thu muc ns2 dm CDROM di kern vao thu muc /usr/local/src: tar xvfz nam-src-1.11.tar.gz tar xvfz ns-src-2.29.tar.gz Chuang &nth Vtron worn Khoa hpc - Ky thugs Tre 101 Nghien ciru mo hint: hOi litho eta dam eltra &On giao IP Multicast tar xvfz otcl-1.11.tar.gz tar xvfz tc18.4.5-src.tar.gz tar xvfz tcicl-1.17.tar.gz tar xvfz tk8.4.5-src.tar.gz tar xvfz xgraph-12.1.tar.gz To thu muc chung /usr/local/nsnam de cai dat cac phAn mem nay: mkdir /usr/local/nsnam a Ghi sir dung cac phien ban mai lion ciia cac phAn mem not tren, c6 the download chung tCr dia chi http://wwvv.isi.edu/nsnam/ 2.2 Cai dat Tel cd /usr/local/src/tc18.4.5/unix configure prefix=/usr/local/nsnam make make test make install 2.3 Cai dat Tk cd /usr/local/src/tk8.4.5/unix configure prefix=/usr/local/nsnam enable-gcc enableshared with-tc1=/usr/local/src/tc18.4.5/unix make make install 2.4 Cai dat OTci cd /usr/local/src/otc1-1.11 configure prefix=/usr/local/nsnam with-tc1=/usr/local/src/tc18.4.5 with-tk=/usr/local/src/tk8.4.5 Chtron trizzh Virow tram Khoa h9c - Ky thtu,t Tre 102 Nghien ctru ma' hinh h"Oi thdo da diint dira tree giao thtic IP Multicast make make install 2.5 Cal slat Tc1CL cd /usr/local/src/tc1c1-1.17 configure prefix=/usr/local/nsnam with-tc1=/usr/local/src/tc18.4.5 \ with-tk=/usr/local/src/tk8.4.5 make make install 2.6 Cai chat ns cd /usr/local/src/ns-2.29 configure prefix=/usr/local/nsnam with-tc1=/usr/local/src/tc18.4.5 with-tk=/usr/local/src/tk8.4.5 with-otcl=/usr/local/src/otcl-1.11 \ with-tcicl=/usr/local/src/tcicl-1.17 make make install 2.7 Cal chat xgraph cd /usr/local/src/xgraph-12.1 configure prefix=/usr/local/nsnam make make install 2.8 Cal slat nam cd /usr/local/src/nam-1.11 configure prefix=/usr/local/nsnam Chlron truth Vtro'n tram Khoa hoc - icy thuot Tre 103 Nghien ciru mo hinh hOi Chao da cam d(ra tren giao Ili.c IP Multicast with-tc1=/usr/local/src/tc18.4.5 \ with-tk=/usr/local/src/tk8.4.5 \ with-otc1=/usr/local/src/otc1-1.11 \ with-tc1c1=/usr/local/src/tc1c1-1.17 make make install Ghi chit: a - GOi nam khong b& butic phai cai d4t chay chtrang trinh mo ph6ng Chi sir dung nam can xem hinh anh dOng minh hoa qua trinh cac g6i tin km thong so mang mo ph6ng - Twang hop khong bier' dich &roc nam voi gcc dm Linux Fedora, ma( file agent.h thu muc /usr/local/src/nam-1.11 va thay chir "NULL" (long 73 so "0" 2.9 DO biin moi trtrovg shell Dang nh4p vao tai khoan ngubi dUng se chay ns Sau d6 da't cac bien moi tnrong sau cho shell tnrac chay ns export PATH =$PATH :/usr/local/nsnam/bin export =$LD_LIBRARY_PATH :/usr/local/nsnam/lib LD LIBRARY_PATH export TCL_LIBRARY=/usr/local/nsna m/lib/tc18.4:/usr/local/nsnam/lib/tk8.4 Ghi chii: gan ttr dOng cac bien moi truemg naymoi 6i ngtred dung Bang nhap, can gan cac gia tri trkrc tiep file bash_profile hay bashrc dm nguoi dung litrofirng clan thwc hi'e'n mo phong Copy file script test-rlm.tcl va test-plm.tcl thu muc simulation cua CDROM di kern vao thu muc lam viec Day la hai clurang trinh mos phong hai ma hinh truyen hinh da diem diing IP Multicast vai giao thirc kiem soat tac , la RLM (phuang phap truyen thong) va Packet Pair (phuong phap de xuat) MOt s6 tham Nen co the tily chinh cac file script nOi tren: Chuang trinh Nam iron Khoa hoc - xy thu(ft Tre 104 Nghien etiu nib hinh hOi thao eta diem chra tren giao there IP Multicast set run_nam => = 0: khong chay nam sau m6 phong = 1: chay nam sau m6 phong 3.1 Truimg hop dung RLM Chay chtrong trinh m6 phong he thong vbi giao thirc kiem soat tic RLM: ns test-rlm.tcl Giao dien minh hoa dung (lir lieu multicast video chay mang thuc hien nam (cac o hinh thoi la nhtrng gOi bi loss): •-%(7,/,./,W.,4"743/4v0;4",W49$.04,9:.wwett.,;gttitinntliKOWNOW4r0,1,444,1Ele Llews 6nalysis 44 out-rlm.nam • 620652 Step: 0M3 C o • IIIIIIIIIIIIIIIIIIII~IIIIIIIIIIIIIIIIIII IIIIIIIIIj I HHIHHIHHII join-group -2147483647 join-group -2147483647 join-group -2147483647 Hinh 36: Minh hoa ICjt qua mo phong Theo phicang phcip RLM 3.2 Truteng hop dung Packet Pair Chay chuong trinh m6 ph6ng he thong vOi giao thirc ki6m soat tic Packet pair: ns test-plm.tcl Giao din minh hoa Bong du lieu multicast video chay mang thiic hien nam: Chtrang trinh Vtratt tram Khoa h9c - K.57" 11541 Tre 105 Nghien cau mo hinh hOi thdo da dant thra tren giao tht& IP Multicast V , igWVeaWaP: e',141(" I 411 '01titril ! 11 ° Elle yields 6nalysis 44 out -plai Alarn • • 0.5041116 Step: 2.0ms - 12) eo it 11111711111111111111 M1111111111111111111111111111111111111 join-group -2147483648 joln- grolip -2147437136,18 Join-group -2147483648 Hinh 37: Minh hoa k"'t qua mo ph6ng theo phtrang phap Packet Pair Ghi chu: tham khao them y nghia cac cau lenh file script qua trang web http://www.isi.eduinsnaminsitutorial/ Ch:rong trinh Vuirn Iron Khoa hoc - Ky thufit Tre 106 Nghien caw mo Itittlt hOi thao eta diim dtfa tren giao tin& IP Multicast TAI LIEU THAM KHAO [1] Le Phuoc Loc, Vo Dinh Hieu, Do Van Long and Tran Van Lang, Multipoint video conferencing program on IP Multicast, 1st Science Conference of IOIT-HCM, 25/03/2004 [2] Le Phuoc Loc, Introduce to contemporary video coding schemes, 1st Science Conference of IOIT-HCM, 25/03/2004 [3] Cac giai phap Video conferencing qua Unicast IP, ISDN dm VTI, VNPT, Hoc vien BCVT, [4]Open H323 — Unicast Video conferencing, http://www.openh323.org [5] IEEE Communications Society, http://www.comsoc.org, [6] Sadka, AH, Compressed Video Communications, J Wiley and Co, 2001 [7] S McCanne, V Jacobson, and M Vetterli, Receiver-driven layered multicast, ACM SIGCOMM'96, 1996 [8] T Turletti, S.F Parisis, and J Bolot, Experiments with a layered transmission scheme over Internet, INRIA Research Report No 3296, Nov 1997 [9] B J Vickers, C Albuquerque, and T Suda, Adaptive Multicast of Multi-layered Video: Rate-based and Credit-based Approaches, Proc of IEEE INFOCOM'98, 1998 [10] H.M Smith, M.W Mutka, and E Torng, Bandwidth Allocation for Layered Multicasted Video [11] J Liu, B Li, and Y.Q Zhang, An End-to-End Adaptation Protocol for Layered Video Multicast Using Optimal Rate Allocation, IEEE Transactions on Multimedia, Vol 6, No 1, Feb 2004 [12] Q Ni, Q Zhang, and W Zhu, SARLM: Sender-adaptive & Receiverdriven Layered Multicasting for Scalable Video [13] S McCanne and S Floyd, The LBNL Network Simulator, ns-2, http://www.isi.edu/nsnam/ns [14] S Wenger, Y Wang and M Hannuksela, RTP payload format for H.264/SVC scalable video coding, Zhejiang University Press, Vol 7, No 5, May 2006 Chuvng trinh Yuen! tram Khoo hoc - Ky 11141 Tre 107