Tim Hieu Cong Nghe Iptv 3294

LI CM N

Vi lng bit n su sc ca mnh, em xin gi li cm n n:

Thy L Duy Khnh, ngi trc tip hng dn em hon thnh ni dung bo co lun vn tt nghip.

Qu thy c trong Hc vin cng ngh bu chnh vin thng c s ti TPHCM, c bit l cc thy c khoa in t - Vin thng II, nhng ngi tn tnh ging dy trang b kin thc em hon thnh c bo co lun vn tt nghip. V nhng kin thc cng s l nn tng cho tng lai ngh nghip ca em sau ny.

Gia nh v cc bn lp D07VTH1, nhng ngi ng vin v chia s vi em trong sut thi gian hc tp ti Hc vin.

Cm n mi ngi rt nhiu! Trn Trung Hiu

i

LI M U

Ngy nay, truyn hnh da trn giao thc Internet IPTV ang pht trin mnh m

v tin ti v tr ch cht trong cng nghip truyn hnh thu ph, v cng l dch v thu ht c s ch ca rt nhiu cc cng ty vin thng trn th gii. IPTV l mt h thng nhiu tin ch, bn c th nhn c tn hiu truyn hnh v video song song vi cc dch v a phng tin khc trn cng mt kt ni Internet. C th, IPTV s dng mt kt ni bng rng v mt h thng mng phn phi cc chng trnh truyn hnh s dng giao thc IP.

Trn th gii IPTV c trin khai mnh m v thu c li nhun rt ln. Ti Vit Nam, IPTV c cng ty FPT cung cp u tin vo thng 3 nm 2006, v u thng 5 nm 2009, VNPT bt u cung cp IPTV ti Hi Phng. Nh vy, c th thy th trng IPTV ti Vit Nam mi ch giai on bt u v th tim nng pht trin l rt ln.

Vi s hng dn ca thy L Duy Khnh v mong mun hiu c cng ngh mi, sau mt thi gian tm hiu em hon thnh c cun bo co lun vn tt nghip vi ti Tm hiu cng ngh IPTV. Ni dung ca bo co gm c phn L thuyt v Thc hnh c trnh by trong 4 chng nh sau:

Chng I: Tng quan v IPTV. Chng ny trnh by khi nim v IPTV, cu

trc mng IPTV, vn phn phi IPTV, cc cng ngh cho IPTV v cui cng l mt s dch v v ng dng ca IPTV.

Chng II: Cc gii php phn phi mng IPTV. Chng ny a ra cc gii php trin khai mng phn phi ni dung IPTV. IPTV c th c trin khai trn cc mng sau: mng truy cp si quang, mng ADSL, mng truyn hnh cp v mng Internet. Ngoi ra, chng ny cn tm hiu mt s cng ngh mng li cho mng IPTV.

Chng III: Qun l mng IPTV. Chng ny tm hiu v h thng qun l mng IPTV; cc vn v qun l ci t, cc s c, qun l d phng, qun l QoS. Ngoi ra, chng ny cn tm hiu vic gim st, kim tra v x l cc s c trn mng IPTV.

Chng IV: Tm hiu thit b phn cng v chng trnh phn mm trong mng IPTV. Chng ny tm hiu v cc thit b phn cng trong trung tm d liu Headend v mng gia nh. Bn cnh l cc phn mm chuyn dng trong h thng mng IPTV v mt s chng trnh Media Player xem ni dung trn my tnh c nhn.

Do IPTV l cng ngh mi v kh nng kin thc cn hn ch nn cc lp lun,

nh gi, trnh by trong bo co cha c r rng. Tuy vy, ni dung bo co c th lm ti liu tham kho cho cc bn mun tm hiu v nm r mt s vn c bn ca cng ngh IPTV. V qua cng mong nhn c s ng gp kin ca cc bn c bo co c hon thin hn.

Sinh vin thc hin Trn Trung Hiu

ii

MC LC

Trang LI M U ...........................................................................................................i MC LC.................................................................................................................ii Danh mc hnh v......................................................................................................iv Danh mc bng biu ..................................................................................................iv Chng I TNG QUAN V IPTV ...........................................................................1

1.1 Khi nim IPTV ..............................................................................................1 1.2 Cu trc mng IPTV ........................................................................................2

1.2.1 C s h tng mng IPTV .....................................................................2 1.2.2 Cu trc chc nng cho dch v IPTV ....................................................3

1.3 Vn phn phi IPTV ...................................................................................6 1.3.1 Unicast ...................................................................................................6 1.3.2 Broadcast ..............................................................................................7 1.3.3 Multicast ................................................................................................7

1.4 Cc cng ngh cho IPTV ................................................................................7 1.4.1 Vn x l ni dung.............................................................................8 1.4.2 VoD v Video server .............................................................................9 1.4.3 Cc h thng h tr hot ng ................................................................11

1.5 Cc dch v v ng dng ca IPTV ..................................................................11 1.5.1 Truyn hnh qung b k thut s ...........................................................12 1.5.2 Video theo yu cu VoD .........................................................................12 1.5.3 Qung co c a ch...............................................................................12

TM TT ..............................................................................................................13 Chng II CC K THUT PHN PHI MNG IPTV ........................................14 2.1 Cc loi mng truy cp bng rng ........................................................................14

2.2 IPTV phn phi trn mng truy cp cp quang ................................................14 2.2.1 Mng quang th ng .............................................................................15 2.2.2 Mng quang tch cc...............................................................................18

2.3 IPTV phn phi trn mng ADSL.....................................................................18 2.3.1 ADSL .....................................................................................................19 2.3.2 ADSL2 ...................................................................................................21 2.3.3 VDSL .....................................................................................................21

2.4 IPTV phn phi trn mng truyn hnh cp.......................................................22 2.4.1 Tng quan v k thut HFC ....................................................................23 2.4.2 IPTV phn phi trn mng truyn hnh cp.............................................24

2.5 IPTV phn phi trn mng Internet ..................................................................26 2.5.1 Cc knh truyn hnh Internet streaming.................................................26 2.5.2 Download Internet .................................................................................28 2.5.3 Chia s video ngang hng .......................................................................28

2.6 Cc cng ngh mng li ...................................................................................28 2.6.1 ATM v SONET/SDH............................................................................29 2.6.2 IP v MPLS ............................................................................................30 2.6.3 Metro Ethernet........................................................................................31

TM TT ..............................................................................................................32

iii

Chng III QUN L MNG IPTV .......................................................................33

3.1 H thng qun l IPTV ....................................................................................33 3.1.1 S dng giao thc SNMP qun l IPTV ............................................35 3.1.2 Qun l thit b bng trnh duyt web .....................................................38

3.2 Qun l ci t..................................................................................................39 3.3 Gim st thc thi v kim tra mng ..................................................................40 3.4 Qun l d phng .............................................................................................42 3.5 Qun l khng gian a ch IP...........................................................................43 3.6 X l cc s c IPTV .......................................................................................44 3.7 Qun l quyn ni dung s ...............................................................................45 3.8 Qun l cht lng dch v QoS.......................................................................46

3.8.1 kh dng ca mng............................................................................46 3.8.2 Phn lp dch v .....................................................................................47 3.8.3 Cc cam kt cp dch v.....................................................................48

TM TT ..............................................................................................................49 Chng IV TM HIU THIT B PHN CNG V CHNG TRNH PHN MM TRONG MNG IPTV ....................................51

4.1 Thit b phn cng trung tm Headend .............................................................51 4.1.1 Thit b tip nhn d liu u vo ...........................................................51 4.1.2 B m ha video MPEG .........................................................................53 4.1.3 B ng gi IP ........................................................................................53 4.1.4 B chuyn i m video..........................................................................53 4.1.5 Server qun l ni dung ..........................................................................54 4.1.6 Kho video ...............................................................................................54 4.1.7 Video Streaming server ..........................................................................54 4.1.8 Middleware server ..................................................................................54

4.2 Thit b mng gia inh......................................................................................56 4.2.1 Mng gia nh..........................................................................................56 4.2.2 B gii m IP-STB .................................................................................56

4.3 Cc chng trnh phn mm .............................................................................59 4.3.1 Hng dn chng trnh EPG.................................................................59 4.3.2 H thng truy cp c iu kin................................................................60 4.3.3 H thng VoD.........................................................................................60 4.3.4 H thng qun l quyn truy cp ni dung s..........................................60 4.3.5 H thng qun l thu bao v lp ha n...............................................61

4.4 Cc chng trnh Media Player ........................................................................61 4.1 Microsoft ...................................................................................................61 4.2 RealNetwork..............................................................................................62 4.3 Apple Computer ........................................................................................63

TM TT ..............................................................................................................64

KT LUN ...............................................................................................................65 THUT NG VIT TT .........................................................................................66 TI LIU THAM KHO..........................................................................................69

iv

DANH MC HNH V

Hnh 1.1 M hnh h thng IPTV end-to-end.............................................................2 Hnh 1.2 Cu trc chc nng cho dch v IPTV .......................................................4 Hnh 1.3 Cc thnh phn ca cu trc chc nng .......................................................5 Hnh 1.4 Cc kt ni IP unicast cho nhiu user IPTV ................................................6 Hnh 1.5 Cc kt ni c s dng trong k thut multicast .....................................8 Hnh 1.6 Cu trc h thng VoD................................................................................9 Hnh 1.7 M hnh trin khai server ............................................................................10 Hnh 2.1 Mng IPTV FTTH s dng cng ngh PON................................................16 Hnh 2.2 IPTV trn cu trc mng ADSL ..................................................................20 Hnh 2.3 Mng HFC end-to-end ................................................................................24 Hnh 2.4 M hnh trin khai cu trc mng IPTV cp kt hp IP v RF.....................26 Hnh 2.5 Cu trc mng cc knh truyn hnh Internet ..............................................27 Hnh 2.6 H tng mng li IPTV ...............................................................................29 Hnh 2.7 Topology mng li MPLS...........................................................................31 Hnh 2.8 S dng cc EVC cung cp kt ni IPTV qua li mng ..........................32 Hnh 3.1 H thng SNMP n gin ...........................................................................36 Hnh 3.2 Lin kt h thng qun l mng IPTV ........................................................38 Hnh 3.3 Cu trc qun l da trn trnh duyt web ...................................................39 Hnh 3.4 Thit k mng h tr d phng....................................................................42 Hnh 3.5 M hnh khi h thng DRM n gin ........................................................46 Hnh 3.6 V d s dng ba hng i c quyn u tin ...............................................48 Hnh 4.1 Cu trc trung tm Headend IPTV ..............................................................52 Hnh 4.2 Cu trc h thng Middleware IPTV ...........................................................55 Hnh 4.3 Cu trc IP-STB .........................................................................................57 Hnh 4.4 Tin trnh x l ca IP-STB ........................................................................59

DANH MC BNG BIU

Bng 2.1 So snh cc cng ngh mng PON: BPON, EPON v GPON .....................18 Bng 2.2 So snh cc cng ngh mng DSL ..............................................................23 Bng 2.3 Cc chun OC SONET ...............................................................................29 Bng 2.4 nh dng MPLS header.............................................................................30

Bo co lun vn tt nghip Chng I: Tng quan v IPTV

Trn Trung Hiu D07VTH1 1

CHNG I

TNG QUAN V IPTV

Truyn hnh k thut s l tin b quan trng nht trong cng ngh truyn hnh t khi phng tin ny c to ra trong th k trc. Truyn hnh k thut s a ra cho khch hng nhiu s la chn v to ra nhiu tng tc hn. H thng truyn hnh qung b tng t c s dng rt tt trong hn 60 nm qua. Trong giai on , ngi xem phi tri qua s chuyn tip t truyn hnh en trng sang truyn hnh mu yu cu ngi xem phi mua cc Tivi mu mi, v cc knh qung b phi c cc my pht mi, cc thit b sn xut chng trnh mi. Ngy nay, vi s pht trin ca ngnh cng nghip truyn hnh s a truyn hnh thng thng sang thi i ca truyn hnh k thut s. Hu ht cc hot ng ca truyn hnh phi c nng cp v trin khai da trn k thut s a ti cho khch hng cc dch v k thut s tinh vi hn. Mt k thut mi c gi l truyn hnh da trn giao thc Internet IPTV (Internet Protocol based Television). Nh tn gi, IPTV c miu t nh l mt c ch truyn ti lung ni dung truyn hnh da trn nn tng l mt mng s dng giao thc IP. Li ch ca c ch ny l kh nng phn phi nhiu loi tn hiu truyn hnh khc nhau, tng cc tnh nng tng tc v ci tin tng thch vi cc mng thu bao ang tn ti. Trong chng ny s trnh by khi nim v IPTV, cu trc mng IPTV, vn phn phi IPTV, cc cng ngh cho IPTV, cui cng l cc ng dng v dch v ca IPTV. 1.1 Khi nim IPTV

Cng ngh IPTV ang gi phn quan trng v c hiu qu cao trong cc m hnh kinh doanh truyn hnh thu ph. Nhng thc cht ngha ca t vit tt IPTV l g v nh hng ca n i vi ngi xem truyn hnh nh th no?

Khi mi bt u IPTV c gi l Truyn hnh giao thc Internet (Internet Protocol Television) hay Telco TV hoc Truyn hnh bng rng (Broadband Television). Thc cht tt c cc tn u c s dng ni n vic phn phi truyn hnh bng rng cht lng cao hoc ni dung m thanh v hnh nh theo yu cu trn mt mng bng rng. IPTV l mt nh ngha chung cho vic p dng phn phi cc knh truyn hnh truyn thng, phim truyn, v ni dung video theo yu cu trn mt mng ring. T gc nhn ca ngi s dng th IPTV ch hot ng nh mt chun dch v truyn hnh tr tin. T gc nhn ca nh cung cp th IPTV bao gm vic thu nhn, x l v phn phi chnh xc ni dung truyn hnh ti thu bao thng qua mt h tng mng s dng IP. Theo nh ngha c a ra bi hip hi vin thng quc t tp trung vo nhm IPTV th IPTV l cc dch v a phng tin (v d nh d liu truyn hnh, video, m thanh, vn bn, ha) c phn phi trn mt mng IP c s qun l cung cp cc mc yu cu v cht lng ca dch v, an ton, c tnh tng tc v tin cy. IPTV c mt s im c trng sau:

H tr truyn hnh tng tc: kh nng ca h thng IPTV cho php cc nh

cung cp dch v phn phi y cc ng dng ca truyn hnh tng tc. Cc dng dch v IPTV c th c phn phi bao gm chun truyn hnh trc tip, truyn hnh hnh nh cht lng cao HDTV (High Definition Television), cc tr chi tng tc v truy cp Internet tc cao.



Dch thi gian: IPTV kt hp vi mt b ghi hnh video s cho php dch

chuyn thi gian xem ni dung chng trnh, y l mt k thut ghi hnh v lu tr ni dung c th xem li sau.

Tnh c nhn: mt h thng IPTV end-to-end h tr thng tin c tnh hai chiu v cho php cc user xem cc chng trnh theo s thch, thi quenHay c th hn l cho cc user xem ci g h mun vo bt k lc no.

Yu cu bng thng thp: thay th cho vic phn phi mi knh cho mi user, cng ngh IPTV cho php cc nh cung cp dch v ch phn phi cc knh m user yu cu. y l c im hp dn cho php cc nh khai thc mng bo ton c bng thng ca h.

Nhiu thit b c th s dng c: vic xem ni dung IPTV khng gii hn cho Tivi. Khch hng c th s dng PC ca h v cc thit b di ng truy cp cc dch v IPTV.

1.2 Cu trc mng IPTV

C rt nhiu ti liu trnh by cu trc ca mng IPTV, trong phn ny trnh by cu trc mng IPTV theo hai vn . Th nht l c s h tng ca mng IPTV, a ra cc thnh phn ca mt h thng IPTV end-to-end. Vn th hai l cu trc chc nng cho dch v IPTV, ni dung phn ny ni ln chc nng ca tng thnh phn c th tham giao vo cng vic phn phi ni dung IPTV.

1.2.1 C s h tng ca mng IPTV

Hnh 1.1 l m hnh mt h thng IPTV end-to-end.

Hnh 1.1 M hnh h thng IPTV end-to-end

1.2.1.1 Trung tm d liu IPTV

Trung tm d liu IPTV (IPTV Data Center) hay Headend l ni nhn ni dung t nhiu ngun khc nhau, bao gm video ni b, cc b tp trung ni dung, cc nh sn xut ni dung v cc knh truyn hnh v tinh, mt t, truyn hnh cp. Mi ln



nhn nh vy, mt s thnh phn phn cng khc nhau nh b gii m, cc server video, cc router IP v cc phn cng bo an chuyn dng u c s dng chun b ni dung s c phn phi trn mng IP. Cng vi mt h thng qun l thu bao IPTV v thuc tnh (profile) v ha n thanh ton. Ch rng, v tr vt l ca trung tm d liu IPTV s c xc nh bi nh cung cp dch v s dng h tng mng. 1.2.1.2 Mng phn phi bng rng

Vic phn phi cc dch v IPTV theo yu cu kt ni one-to-one, nu trong trng hp vic trin khai IPTV trn din rng th s kt ni one-to-one s tng ln. Do , yu cu v bng thng trn mng l kh ln. Nhng tin b v cng ngh mng cho php cc nh cung cp vin thng c c mt s lng ln cc mng bng rng. Ring mng truyn hnh cp th s dng hn hp c cp ng trc v cp quang p ng cho vic phn phi ni dung IPTV.

1.2.1.3 Thit b khch hng IPTVCD

Thit b khch hng IPTVCD (IPTV Consumer Device) l cc thnh phn cho php user truy cp dch v IPTV. IPTVCD kt ni ti mng bng rng, chng m nhim chc nng gii m, x l cc lung tn hiu ti t mng IP. IPTVCD c h tr cc k thut tin tin ti thiu ha hoc loi tr hon ton nh hng ca cc vn v mng khi x l ni dung IPTV. C rt nhiu dng IPTVCD nh gateway cho khu dn c, b gii m set-top boxes, bng iu khin tr chi 1.2.1.4 Mng gia nh

Mng gia nh lin kt cc thit b k thut s bn trong mt khu vc c din tch nh. N ci thin thng tin v cho php chia s ti nguyn gia cc thnh vin trong gia nh. Mc ch ca mng gia nh l cung cp quyn truy cp thng tin gia cc thit b k thut s xung quanh nh thu bao. Vi mng gia nh, khch hng c th tit kim tin v thi gian do vic chia s cc thit b phn cng rt tt v d dng, thng qua cc kt ni Internet bng rng. 1.2.2 Cu trc chc nng cho dch v IPTV

Mt mng IPTV c th bao gm nhiu thnh phn c bn, n cung cp mt cu trc chc nng cho php phn bit v chuyn mn ho cc nhim v. Hnh 1.2 chnh by su thnh phn chnh ca cu trc chc nng c to thnh bi cc chc nng sau: cung cp ni dung, phn phi ni dung, iu khin IPTV, truyn dn IPTV, thu bao v bo an. 1.2.2.1 Cung cp ni dung

Tt c ni dung c s dng bi dch v IPTV, bao gm VoD v truyn hnh qung b s phi thng qua chc nng cung cp ni dung, cc chc nng tip nhn, chuyn m v m ha s to nn cc lung video s c kh nng c phn phi qua mng IP. 1.2.2.2 Phn phi ni dung

Khi phn phi ni dung bao gm cc chc nng chu trch nhim v vic phn phi ni dung c m ho ti thu bao. Thng tin nhn t cc chc nng vn truyn v iu khin IPTV s gip phn phi ni dung ti thu bao mt cch chnh xc. Chc nng phn phi ni dung s bao gm c vic lu tr cc bn copy ca ni



dung tin hnh nhanh vic phn phi, cc lu tr tm thi (cache) cho VoD v cc bn ghi video c nhn. Khi chc nng thu bao lin lc vi chc nng iu khin IPTV yu cu ni dung c bit, th n s gi ti chc nng phn phi ni dung c c quyn truy cp ni dung.

Ch

c nng thu bao

Hnh 1.2 Cu trc chc nng cho dch v IPTV

1.2.2.3 iu khin IPTV Cc chc nng iu khin IPTV l tri tim ca dch v. Chng chu trch nhim

v vic lin kt tt c cc chc nng khc v m bo dch v hot ng cp thch hp tho mn nhu cu ca khch hng. Chc nng iu khin IPTV nhn yu cu t thu bao, lin lc vi chc nng phn phi v vn chuyn ni dung m bo ni dung c phn phi ti thu bao. Mt chc nng khc ca iu khin IPTV l cung cp hng dn chng trnh in t EPG (Electronic Program Guide), EPG c thu bao s dng chn ni dung theo nhu cu. Chc nng iu khin IPTV cng s chu trch nhim v qun l quyn ni dung s DRM (Digital Rights Management) c yu cu bi thu bao c th truy cp ni dung. 1.2.2.4 Chc nng vn chuyn IPTV

Sau khi ni dung yu cu t thu bao c chp nhn, chc nng vn chuyn IPTV s chu trch nhim truyn ti ni dung ti thu bao, v cng thc hin truyn ngc li cc tng tc t thu bao ti chc nng iu khin IPTV. 1.2.2.5 Chc nng thu bao

Chc nng thu bao bao gm nhiu thnh phn v nhiu hot ng khc nhau, tt c u c s dng bi thu bao truy cp ni dung IPTV. Mt s thnh phn chu trch nhim lin lc thng tin vi chc nng truyn dn, v d nh truy cp getway kt ni vi DSLAM, hay trnh STB s dng trnh duyt web kt ni vi Middleware server. Trong chc nng ny, STB lu tr mt s cc thnh phn quan trng nh cc key DRM v thng tin xc thc user. Khi chc nng thu bao s s dng EPG cho



php khch hng la chn hp ng truy cp v yu cu n t cc chc nng iu khin IPTV. N cng nhn cc giy php s v cc key DRM truy cp ni dung. 1.2.2.6 Bo an

Tt c cc chc nng trong m hnh IPTV u c h tr cc c ch bo an ti cc cp khc nhau. Chc nng cung cp ni dung s c b phn mt m c cung cp bi nh cung cp ni dung. Chc nng phn phi ni dung s c m bo thng qua vic s dng DRM. Cc chc nng iu khin v vn chuyn s da vo cc chun bo an trnh cc thu bao khng c xc thc c quyn sa i v truy cp ni dung. Chc nng thu bao s b gii hn s dng cc c ch bo an c trin khai ti STB v Middleware server. Tm li, tt c cc ng dng v cc h thng hot ng trong mi trng IPTV s c cc c ch bo an lun sn sng c s dng trch cc hot ng tri php.

Cc thnh phn trong mi trng IPTV s tng ng vi cc chc nng. V d, chc nng iu khin IPTV bao gm cc thnh phn Middleware v qun l quyn ni dung s DRM. Khi phn phi cc nhim v, mt nhm ph trch cc chc nng iu khin IPTV s c kh nng sp xp tt c cc ng dng tng ng vi cc thnh phn cho chc nng . Hnh 1.3 m t cc thit b thc hin cc chc nng trong mi trng IPTV.

Hnh 1.3 Cc thnh phn ca cu trc chc nng



1.3 Vn phn phi IPTV

Cc kiu lu lng mng IP thi gian thc khc nhau c to ra bi cc loi dch v trn nn IP khc nhau nh VoIP v truy cp Internet tc cao. Vi mi loi dch v c nhng c im ring v ni dung, v th cn phi c nhng phng thc phn phi thch hp. Hin nay c ba phng thc dng phn phi ni dung IPTV qua mng IP l unicast, broadcast v multicast. 1.3.1 Unicast

Trong truyn unicast, mi lung video IPTV u c gi ti mt IPTVCD. V th, nu c nhiu hn mt user IPTV mun nhn knh video tng t th IPTVCD s cn ti mt lung unicast ring r. Mt trong cc lung s truyn ti cc im ch qua mng IP tc cao. Nguyn tc thc thi ca unicast trn mng IP l da trn vic phn phi mt lung ni dung c nh hng ti mi user u cui. T gc ca k thut ny, th vic cu hnh thc thi kh d dng; tuy nhin n khng c hiu qu v bng thng mng. Hnh 1.2 trnh by vic thit lp cc kt ni khi c 5 thu bao IPTV truy cp mt knh broadcast trn mng tc cao hai chiu (two-way).

Mng bng rng IP li

RouterPhn phi

Router bin 2

Router bin 1

Thit b truy cp

mng bng rng

Thit b truy cp mng bng rng

Server ni dung

IPTV

IP STB

`

Gateway

IP STB

IP STB

IP STB

Gateway

Gateway

Gateway

Gateway 5 Knh 10 IPTV

Trung tm d liu IPTV

Tng i Khu vc 1

Digital home 1

Tng i Khu vc 2

Digital home 4

Digital home 3

Digital home 2

Digital home 5

Hnh 1.4 Cc kt ni IP unicast cho nhiu user IPTV

Nh trn hnh 1.4, khi nhiu user IPTV truy cp cng mt knh IPTV ti cng

mt thi im, th mt s cc kt ni nh hng c thit lp qua mng. Trong v d ny, server cn cung cp kt ni ti mi thu bao c yu cu truy cp Knh 10, vi tng s l nm lung ring r bt u t server ni dung v kt thc ti router ch.



Nm kt ni ny sau c nh tuyn ti cc im ch ca n. Cc kt ni c ko di ti hai tng i khu vc (Regional Office), vi ba kt ni ti tng i khu vc 1 v hai kt ni ti tng i khu vc 2. Sau cc kt ni c thit lp gia cc router ti tng i khu vc vi cc getway t trong nm h gia nh. y l phng thc truyn dn IP video tt cho cc ng dng theo yu cu nh VoD, mi thu bao nhn mt lung duy nht. 1.3.2 Broadcast

Cc mng IP cng h tr chc nng truyn broadcast, v mt no ging nh knh IPTV c a ti mi thit b truy cp c kt ni vo mng bng rng. Khi mt server c cu hnh truyn broadcast, mt knh IPTV gi ti tt c cc thit b IPTVCD c kt ni vo mng bt chp thu bao c yu cu knh hay khng. y s l vn chnh do cc ti nguyn IPTVCD bt buc phi hot ng x l cc gi tin khng mong mun. Mt vn khc m broadcast khng ph hp cho cc ng dng IPTV l trong thc t k thut truyn thng tin ny khng h tr vic nh tuyn. T lu, hu ht cc mng m rng vic s dng cc router, nhng nu truyn broadcast th khng s dng nh tuyn. y l l do lm mng v cc thit b IPTVCD khc b trn ngp khi tt c cc knh c gi ti tt c mi ngi. 1.3.3 Multicast

Trong phm vi trin khai IPTV, mi nhm multicast c truyn broadcast cc knh truyn hnh v cc thnh vin ca nhm tng ng vi cc thit b IPTVCD. V th, mi knh IPTV ch c a ti IP-STB mun xem knh . y l cch hn ch c lng tiu th bng thng tng i thp v gim gnh nng x l trn server. Hnh 1.5 m t tc ng ca vic s dng k thut multicast trong v d phn phi cho nm thu bao truy cp Knh 10 IPTV cng mt lc.

Nh hnh 1.5, ch bn copy n (single) c gi t server ni dung ti router phn phi. Router ny s to ra hai bn copy ca lung thng tin ti v gi chng ti cc router t ti cc tng i khu vc theo cc kt ni IP nh hng. Sau , mi router s to ra cc bn copy khc cung cp cho cc thu bao mun xem. Vai tr quan trng ca phng thc ny l lm gim s kt ni IP v dung lng d liu i ngang qua mng. y l phng thc thng c cc nh cung cp dch v s dng pht qung b cc chng trnh trc tip v l mt k thut c hiu sut cao cho h tng mng IP ang tn ti. Phng thc ny khng c li trong tuyn hng ln (upstream) lung thng tin gia cc thit b IPTVCD v broadcast server. Cn ch rng, vic pht multicast ni dung IPTV thng phc tp hn nhiu nu so snh vi m hnh thng tin unicast v broadcast. 1.4 Cc cng ngh cho IPTV

C nhiu cng ngh khc nhau c yu cu thc thi y h thng IPTV trong thc t, mt s cng ngh chung c din gii trong cc ti liu khc. Trong phn ny ch cp ti mt s cng ngh c bn c s dng cho cc ng dng IPTV.



Mng bng rng IP li

RouterPhn phi

Router bin 2

Router bin 1

Thit b truy cp

mng bng rng

Thit b truy cp mng bng rng

Server ni dung

IPTV

IP STB

`

Gateway

IP STB

IP STB

IP STB

Gateway

Gateway

Gateway

Trung tm d liu IPTV

Tng i Khu vc 1

Digital home 1

Tng i Khu vc 2 Digital home 5

Digital home 4

Digital home 3

Digital home 2

Gateway

1 Knh 10 IPTV

Hnh 1.5 Cc kt ni c s dng trong k thut multicast

1.4.1 Vn x l ni dung Cc h thng x l ni dung tip nhn cc tn hiu video thi gian thc t rt

nhiu ngun khc nhau, hnh thc ca chng l mt nh dng thch hp STB c th gii m v hin th trn mn hnh. Tin trnh ny bao gm cc chc nng sau:

Nn: cc ngun video tng t, qu trnh nn s c thc thi trn mi tn

hiu video trc khi n c pht ln h thng IPTV. Tc cao nht ca d liu video v di ca gi tin c thc hin sao cho ph hp vi tt c cc ngun video u vo, v n gin ha cng vic truyn dn v cc chc nng ghp knh.

Chuyn m: cc lung video tng t c nh dng s, i khi n cn c chuyn i sang thuc tnh MPEG hoc cp lung ti thch hp vi cc b STB. Chuyn m ni dung nh dng HD cung cp cc chun chuyn m gc l MPEG-2 thnh H.264 c c bng thng thp hn cho cc mng DSL.

Chuyn i tc : bn cht ca vic chuyn i tc l tin trnh chuyn i tc bit ca lung video s ti. V d nh lung chun SD l 4,5 Mbps c th cn phi gim xung 2,5 Mbps s dng trong h thng IPTV.

Nhn dng chng trnh: mi lung video cn c ghi mt nhn duy nht trong h thng IPTV, do cc thit b ghp knh v cc b STB c th xc nh chnh xc cc lung video. Mi chng trnh audio hay video bn trong



mi lung truyn dn MPEG phi c x l m bo khng c s trng ln chng trnh.

Vic x l ni dung c th c thc thi trn mt lung video trc tip hoc

c lu tr bn trong video server. 1.4.2 VoD v Video server

Cu trc ca h thng VoD s dng cng ngh video-over-IP trn hnh 1.6 bao gm 4 thnh phn chnh. u tin, ni dung phi c x l cho vic lu tr v phn phi bng qu trnh nn v mt m ti trm tin x l ni dung. Mt VoD server lu tr ni dung v to lung gi ti thu bao. Mi thu bao s c mt b STB nhn v gii m ni dung, sau a ln mn hnh hin th. B STB cng cung cp cho thu bao mt danh sch cc dch v t thnh phn qun l thu bao v h thng truy cp c iu kin. y l mt h thng con nhn cc lnh t thu bao, gi nhng lnh thch hp ti VoD server v phn phi cc key gii m cho cc b STB.

Hnh 1.6 Cu trc h thng VoD

Cc video server l yu t cn thit cho mi h thng VoD, do chng to ra cc lung video trong thc t v gi chng ti mi thu bao. Cc server c dung lng b nh ln nh khc nhau ty thuc vo cc ng dng khc nhau. Trong phn ny ch cp n mt s kha cnh ca cc server v cch thc chng c s dng cho vic phn phi ni dung. Dung lng lu tr ni dung c h tr trn mt server c th ln hoc nh. S khng ph hp nu server lu tr nhiu nhng ch phc v mt s t thu bao.

Khi u t xy dng mt server, cn phi ch ti dung lng ca server c th p ng cc yu cu t ra. Video server c th l mt trong cc loi sau:

Cc server sn xut c s dng trong cng vic sn xut cc video, v d

nh trong cc mng truyn hnh. cho cc i tng ny, mt server cn



phi c c ni dung l tng nht trong cc nh dng khc nhau v nhanh chng phn phi cc file cha ni dung ti thu bao khi h cn, cc server ny dung lng thng rt nh. Thay vo , l cc thi b c dung lng ln v h tr tt vic tm ni dung, bao gm cc cng c h tr d liu ln v d liu l cc file gm nhiu phin bn.

Cc server c nhn v cng ty c s dng trong trng hp c s lung video phn phi ng thi thp, v d nh mt gian hng trng by ca cng ty c t 5 n 10 ngi xem cng mt lc. y l loi server thng c xy dng trn PC vi cc phn mm c chuyn dng ha.

Cc nh cung cp server cn cc server c thit k c bit c kh nng lu tr hng nghn gi ni dung chng trnh v kh nng phn phi ti hng trm hoc hng nghn ngi xem cng mt lc. Dung lng ca cc h thng ny tht s rt ln; v d cung cp cho 1000 user cng mt lc, vi mi user l mt lung 2,5 Mbps. Nh vy server cn c tc d liu xut ra l 2,5 Gbps.

Cc nh cung cp s dng hai phng thc phn phi server trong mng ca

h, nh trn hnh 1.7. u tin l phng thc tp trung ha, cc server ln, dung lng cao c xy dng ti nhng v tr trung tm, chng phn phi ni dung cho thu bao thng qua cc lin kt tc cao kt ni ti mi nh cung cp dch v ni ht. Phng thc th hai l phn phi ha server, cc server nh hn c t ti cc v tr gn thu bao v server ch cung cp cho cc thu bao trong vng . Trung tm Library server s download cc bn copy ni dung cung cp cho cc Hub server phn phi c yu cu. Trong phng thc tp trung ha th gim c s lng server cn phi xy dng, gim gi thnh trong vic truyn dn v lu tr ni dung ti cc v tr khc nhau. Cn trong phng thc phn phi ha th gim c s lng bng thng cn thit gia cc v tr. C hai phng thc u c s dng trong thc t, dung lng ca VoD server ph thuc vo cu trc h thng v s thch ca ngi xem.

Hnh 1.7 M hnh trin khai server



1.4.3 Cc h thng h tr hot ng

Vic phn phi cc dch v video ti khch hng yu cu nhiu thit b phn cng c tin cy cao. Mt phn mm ln cng c yu cu qun l s lng cng vic khng l , t vic thng bo cho khch hng v cc chng trnh trn cc knh broadcast khc nhau cho ti d liu cn thit cho vic lp ho n cc dch v m khch hng ng k. Tp trung li, cc h thng phn mm ny gi l h thng h tr hot ng OSS (Operations Support Systems) v n c th bao gm nhiu dng khc nhau. Mt s chc nng c cung cp bi cc h thng IPTV OSS nh sau:

Hng dn chng trnh in t EPG (Electronic Program Guide) cung cp

cho ngi xem lch pht knh broadcast v tn cc chng trnh VoD sn c. Hng dn ny c th bao gm c cc knh broadcast thng qua vic la chn chng trnh hoc hng dn chng trnh tng tc cho php user ln lch cc knh c pht trong tng lai. Mt s cc nh khai thc dch v IPTV s dng cc cng ty bn ngoi cung cp d liu hng dn chng trnh.

H thng phn quyn c yu cu khi cc thu bao ng k xem ni dung thng qua h thng IPTV. H thng ny cn c kh nng kim tra thng tin ti khon ca khch hng, l cn c h thng phn quyn c th p ng cc yu cu ca thu bao hay khng. H thng ny cn kt ni vi h thng lp ho n thu bao.

Truy cp ni dung trc tuyn (e-mail, web) c cung cp bi mt s h thng IPTV, cho php user c th xem ni dung trn PC tng t nh xem trn Tivi nhng khng cn b gii m IP STB.

H thng lp ho n v qun l thu bao s bo qun d liu chnh v mi thu bao, bao gm hp ng, cc chi tit ho n, cc trng thi ti khon, v cc thng s nhn dng thit b.

Cc h thng OSS c th l thnh phn u t chnh ca cc nh cung cp dch v

IPTV v c thi gian ln tin bc. Bi v n m bo cc phn mm cn thit c mua t nhiu nh cung cp khc nhau s thc thi y cc chc nng c la chn bi nh cung cp. Vic tch hp cc h thng ny c th mt nhiu thng, v nhiu cng vic cn c hon thnh trc khi cung cp dch v cho s lng ln thu bao. Hn na, cc chi ph trn l yu t c nh gi d dch v thu ht c 1000 hay 100000 thu bao. Cng nh vy, chi ph lp t cc h thng OSS cn c xem xt cn thn trong k hoch kinh doanh ca cc nh cung cp dch v, vic tnh ton chi ph lp t OSS nm trong giai on u tin ca k hoch trin khai, cc chi ph ny c th vt tri gi thnh ca phn cng h thng cho s lng thu bao thp hn. Hn na, gi thnh bo dng c s d liu s khng c xem xt khi trin khai m hnh kinh doanh cho mt h thng IPTV. 1.5 Cc dch v v ng dng ca IPTV

Cc ng dng cho trin khai IPTV cung cp vic phn phi truyn hnh qung b s cng nh dch v VoD. Nh vy, n cho php cc nh cung cp a ra dch v gi l triple play bao gm truyn hnh, thoi v d liu. H tng mng IPTV cng cung cp hu ht cc ng dng video cng thm sau khi vic lp t h tng mng ti cc v tr ph hp. Nhng trong phn ny ch trnh by mt s dch v c trin khai bi



cc nh cung cp dch v IPTV ti Vit Nam. l truyn hnh qung b k thut s, dch v VoD v qung co c a ch.

1.5.1 Truyn hnh qung b k thut s

Khch hng s nhn c truyn hnh s thng thng bng IPTV. Truyn hnh qung b s c phn phi ti thu bao thng qua truyn hnh cp c nng cp hoc h thng v tinh. S khi u ca cc cng ngh DSL tc cao hn nh ADSL2 v ADSL2+ mang n mt cuc cch mng ln trong lnh vc ny. Vi cc cng ngh tc cao ny cho php IPTV c thm tin cy v tnh cnh tranh vi cc dch v truyn hnh thu ph khc.

IPTV c y kh nng a ra cc dch v cht lng cao khc nhau v nhiu dch v hn so vi cc nh cung cp truyn hnh thu ph cp v v tinh trong qu kh. Mt li ch khc ca IPTV l n c nhiu ni dung v s knh ln hn la chn, ty thuc vo s thch ca khch hng. c bit khch hng c th t chn la ngun ni dung a dng ny.

Chc nng ca truyn hnh qung b thng thng, truyn hnh cp v v tinh l cung cp tt c cc knh ng thi ti nh thu bao. Tuy nhin, IPTV ch phn phi cc knh m khch hng mun xem v n c kh nng cung cp khng gii hn s knh ny. Khch hng s t do iu khin nhng g h mun xem v xem vo bt c lc no h mun. y l c tnh vn c v c th xy ra ca IPTV v n c s kt hp ca kh nng tng tc hai chiu trn nn mng IP. 1.5.2 Video theo yu cu VoD

VoD l dch v cung cp cc chng trnh truyn hnh da trn cc yu cu ca thu bao. Cc dch v truyn hnh c pht i t cc b lu tr phim truyn, chng trnh gio dc hay tin tc thi s thi gian thc. ng dng VoD cung cp cho tng thu bao ring l chn ni dung video v h xem n vo lc thch hp nht.

Khi h tng mng IPTV u tin c thit k th cc ng dng v cc dch v to li nhun nh in thoi video, hi thoi truyn hnh, o to t xa v camera gim st an ninh ti nh u c th cung cp cho khch hng. C thm mt s dch v v c tnh tin tin hn so vi h thng truyn hnh qung b truyn thng. 1.5.3 Qung co c a ch

Thng tin tin nhn c bit hoc ni dung a phng tin gia thit b v khch hng da trn a ch ca h gi l qung co c a ch. a ch c cng b ca khch hng c th bit c thng qua vic xem xt k profile ca ngi xem. N c thc hin bi lnh xc nh d tin nhn qung co ph hp hoc khng ph hp vi ngi nhn. V th, qung co c a ch cho php tnh ton nhanh chng v chnh xc hiu qu ca chin dch qung co.

S hp tc ca ngi xem l din mo ca qung co c a ch. Ngay khi truyn hnh IP c bt u, cc h thng truyn hnh IP c th hi hoc nhc nh ngi xem khai bo tn ca h t danh sch ng k. i li, ngi xem s mun chn tn chng trnh ca h. Ti y, tn chng trnh c mt profile v cc tin nhn qung co c th c la chn, cch xem tt nht l kt ni ti profile ca ngi xem. Bi v, cc c tnh tin tin c a ra ca truyn hnh IP v d nh cc cuc gi ti, e-mail v hng dn chng trnh u nh cc knh u thch, ngi xem c th thc s xem chng.



Thu nhp c to ra bng cch gi cc tin nhn qung co c a ch ti ngi xem, vi cc profile c bit c th ln gp 10 n 100 ln thu nhp t qung co qung b thng thng. Kh nng gi cc qung co thng mi ti mt s ngi xem c bit cho php cc nh qung co c nh c qu u t chnh xc cho qung co c a ch. N cng cho php cc nh qung co th nghim mt s qung co thng mi khc trong cng mt vng ti cng mt thi im.

TM TT

IPTV l mt h thng cho php phn phi cc chng trnh thi gian thc, phim truyn v cc dng ni dung video tng tc khc trn mt mng nn IP. H tng mng IPTV end-to-end c th bao gm tt c hoc mt s thnh phn sau:

Trung tm d liu IPTV l ni chu trch nhim x l v iu ch ni dung

phn phi trn mt mng bng rng. Mng phn phi IPTV bao gm nhiu k thut truyn ti ni dung IPTV t

trung tm d liu ti ngi s dng. B gii m STB hoc cc gateway c t ti nh thu bao cung cp cc

kt ni t Tivi ti mng truy cp IP. Mng gia nh c kh nng phn phi d liu, thoi v video gia cc thit b

khc nhau.

Ngoi cu trc c s h tng, cu trc mng IPTV cn c c th bng cc cu trc chc nng. Cu trc chc nng s c th ha nhim v ca tng thnh phn tham giao vo mng phn phi IPTV. Cu trc chc nng bao gm 6 chc nng: cung cp ni dung, phn phi ni dung, iu khin, vn chuyn, thu bao v bo an.

Khi trin khai mng IPTV phn phi ni dung cho thu bao th vn cn quan tm l cc c ch c s dng. C ba c ch phn phi l unicast, broadcast, v multicast. Ty vo dch v phn phi m c cc c ch phn phi thch hp, v d nh phn phi dch v VoD th cn c ch multicast, ni dung ch c phn phi cho nhng thu bao c yu cu.

IPTV l mt dch v mi, do s c cc cng ngh h tr trin khai. Cc cng ngh cho dch v IPTV l vn x l ni dung, cc VoD v Video server, v cc h thng h tr hot ng. Trong , cng ngh x l ni dung, c th l cc tin b trong k thut nn d liu v cc h thng h tr hot ng l cc cng ngh mi pht trin.

Khi trin khai dch v IPTV, cc nh khai thc thy c kh nng cung cp nhiu loi dch v v tnh ton c doanh thu t dch v ny. Doanh thu t t rt nhiu dch v v ng dng, nhng hin nay c ba loi dch v v ng dng mang li li nhun chnh l truyn hnh k thut s, VoD v qung co c a ch.

Bo co lun vn tt nghip Chng II: Cc k thut phn phi mng IPTV


CHNG II

CC K THUT PHN PHI MNG IPTV

Hin nay IPTV c nhn nhn nh l con ng tt nht phn phi cc dch v truyn hnh k thut s cho khch hng. Bn cht ca IPTV l mt mng phn phi tc cao c lm nn mng phn phi ni dung. Mc ch ca mng ny l truyn ti d liu gia thit b khch hng IPTVCD v trung tm d liu ca cc nh cung cp dch v. N cn lm vic ny m khng nh hng ti cht lng ca lung video c phn phi ti thu bao IPTV, n cng quyt nh cu trc mng v phc tp c yu cu h tr cc dch v IPTV. Cu trc mt mng IPTV gm c hai phn l mng truy cp bng rng v mng tp trung hay backbone. Cc loi mng m rng khc bao gm cc h thng cp, in thoi cp ng, mng khng dy v v tinh c th c s dng phn phi cc dch v mng IPTV tin tin. Phn chnh ca chng ny l tp trung din gii cc cng ngh mng phn phi IPTV. Ngoi ra chng ny cng phn tch cc cng ngh mng li c bn trin khai cc dch v IPTV. 2.1 Cc loi mng truy cp bng rng

Mt thch thc c bn t ra i vi cc nh cung cp dch v l vic cung cp dung lng bng thng trong mng sng gia mng li backbone v thit b u cui ti nh thu bao. C mt s nh ngha c s dng din gii v loi mng ny nh mng mch vng (local loop), mng last mile, mng bin (edge). Nhng trong ti liu ny xin s dng nh ngha l mng truy cp bng rng. C bn loi mng truy cp (c dy dn) bng rng khc nhau c kh nng cung cp cc yu cu v bng thng ca dch v IPTV l:

Mng truy cp cp quang Mng DSL Mng cp truyn hnh Mng Internet Cc nh cung cp khc nhau la chn cc h thng phn phi ty thuc vo iu

kin ti nguyn mng v nhu cu thc t. Cc phn sau a ra mt cch tng qut cc loi mng truy cp bng rng c s dng trong h tng mng IPTV end-to-end.

2.2 IPTV phn phi trn mng truy cp cp quang

i vi IPTV th yu cu v bng thng ln nhng chi ph hot ng phi thp v trnh c cc can nhiu. Do , ngi ta quan tm ti vic s dng mng cp quang ang c sn trin khai cc dch v IPTV. Cc lin kt cp quang cung cp cho khch hng u cui mt kt ni chuyn dng tt nht thun tin cho vic tip nhn ni dung IPTV. Cc cng ngh v sn xut si quang gn y cho kh nng bng thng ln hn, t c th thc thi mt trong cc cu trc mng sau:

Bo co lun vn tt nghip Chng II: Cc k thut phn phi mng IPTV


Cp quang ti khu vc vn phng (FTTRO Fiber to the regional office):

si quang t trung tm d liu IPTV ti khu vc vn phng mt cch gn nht c lp t bi cc cng ty vin thng hoc cng ty cp. Sau si cp ng s c s dng truyn tn hiu ti ngi dng u cui IPTV trong khu vc vn phng .

Cp quang ti vng ln cn (FTTN Fiber to the neighborhood): nh ta bit si quang c tp trung ti cc node, FTTN i hi thit lp si quang t trung tm d liu IPTV ti b chia vng ln cn. y l v tr node c khong cch nh hn 1,5 Km tnh t nh thu bao. Vic trin khai FTTN cho php ngi dng nhn mt gi cc dch v tr tin bao gm truyn hnh IPTV, truyn hnh cht lng cao v video theo yu cu.

Cp quang ti l ng (FTTC Fiber to the curd ): si quang c lp t t trung tm d liu IPTV ti cc t cp c t ti l ng. T mt si dy cp ng hoc cp ng trc c s dng ni t u cui cp quang trong t cp ti v tr thit b IPTV ca nh thu bao.

Cp quang ti nh khch hng (FTTH Fiber to the home): vi si quang ti nh khch hng, ton b cc nh tuyn t trung tm d liu IPTV ti nh khch hng u c kt ni bi si quang ny. FTTH da trn mng quang c kh nng phn phi dung lng d liu cao ti ngi s dng trong h thng. FTTH l h thng thng tin song knh v h tr tnh nng tng tc ca cc dch v IPTV.

Vic phn phi nhng cu trc mng ny thng c trin khai bng hai loi

mng khc nhau mt cht l mng quang th ng v mng quang tch cc. 2.2.1 Mng quang th ng

Mng quang th ng PON (Passive Optical Network) l cng ngh mng kt ni im a im. Mng s dng cc bc sng khc nhau truyn d liu t trung tm d liu IPTV ti cc im ch m khng c cc thnh phn in. Mng quang th ng c xy dng da trn cc mng FTTx theo cc tiu chun quc t. Tiu chun G.983 ca ITU l tiu chun ang c s dng hin nay.

Mng PON theo tiu chun G.983 bao gm mt kt cui ng quang OLT (Optical Line Termination) c t ti trung tm d liu IPTV v mt s cc kt cui mng quang ONT (Optical Network Termination) c lp t ti thit b u cui ngi dng. Trong trng hp ny, cc k thut truyn ti d liu tc cao trn cp ng c s dng (v d nh DSL) truyn cc tn hiu IPTV vo thit b u cui ca mi h gia nh.

Kt cui ng quang OLT bao gm cp quang v cc b chia quang nh tuyn lu lng mng ti cc kt cui mng quang ONT.

Cp quang: kt cui OLT v cc ONT khc nhau c kt ni vi nhau bng

cp quang. Vi truyn dn bng cp quang th can nhiu thp v bng thng cao. Theo tiu chun G.983 cho php mng PON truyn cc tn hiu nh sng c s ha vi khong cch ti a l 20 Km m khng s dng b khuch i.

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Tim Hieu Cong Nghe Iptv 3294