CONG NGHE VIEN THONG
XU THG HOI TU TRONG UNH VUC TRUV6N THONG
Truyen thong bao gom Vien thong, I n t e r n e t , Phat t h a n h , truyen hinh..
M i c du hien tai cac giai phap l(y thuat thu'c hien cac mang nay van phat trien theo sir doc lap tu'dng doi vdi nhau nhurng net chu dao dang du'dc ky vong va cung dang d i i n ra trong thu'c te la sur hinh thanh cua mpt moi tru'dng tich hdp chung, moi tru'dng nay lam nen tang cho cac dich vu truyen thong hdp nhat (UC- Unified Commnication). Sur chuyen doi theo xu hiTdng nay dien ra trong cac khia canh khac nhau: tuTphia thiet bj ngu'di dung cuoi, phu'dng thuTc truy nhap, mang chuyen tai va giai phap cung cap djch vu... Bai bao gidi thieu mot so thong t i n ve sd cur cung nhii cac y tu'dng va giai phap cho sur chuyen doi hu'dng den moi tru'dng truyen thong hdp nha't nay.
Nguyen Trung Kien, Nguyen Dinh X u i n
M O I T R l / a N G TRUYEN THONG DA DANG Tmydn thbng theo nghia don giin li sir trao ddi thbng tta. Tuy nhien, tuy khoang each tmydn tta, loai thbng tta vi eich thQe trao ddi giua ddi tugng cap tta vi ngubi nhin tta din ddn cie giii phip ky thuat khae rtaau, vi du:
- Viee trao ddi thbng tin giua 2 (hoae mbt rtabm ca nhan) can thidt lap eie keita trao ddi thbng tta rieng (conversation)
- Cac thbng tta tdng hgp hubng den sd lugng lbn ngubi rtaim phuc vu cie rtau cau tta tQc, giai tri thi
General SmiCB PBrBOHlizfld[Patm) Per9onali7ing(Aelm]
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Dob
Hinh 1: Cac loai hinh thong tin
3 2 I TAP CHI CNTT&TT KY 1 (5.2010)
taubng dugc phat quang bi (broadcast)
- Cic thbng tta dugc phit quing b i tbi mbt nhbm han ehd ngubi (mutitcast), vi du mbt nhbm eimg xem mbt phim.
- V.V..
Cae thbng tta ttao ddi duge bieu dien dubi cae hinh thQc khac nhau (tinh da phuong tten): ttdng nbi, htah arta, van ban, miu sic... vi cie thbng tta niy duge cam nhin boi eic giac quan khie nhau eua eon ngubi nhu mit, mm, tai.... Cie phuong tien truyen dat dugc phit trien trube diy thubng dugc thidt kd tdi uu cho eie loai thbng tta, ching han, tta hieu radio su dung ttong dii phit tharta mang cie thbng tta gigng nbi tu cic phit thirta vien den tai ngubi nghe, tmyen hinh mang ca tidng nbi vi htah arta den ngubi xem. Sir htah thirta cac he thdng eung cap thbng tta citag rtau timg nhbm khich hing tao nen vb vin eic mang thbng tin dbc lap: cic dii phat thirta, eie co quan thbng tan, dii tmydn htah..
Thbng tta li mbt til nguysn quy gii, vbi ngubi cb thbng tta thi lim sao ban cho cing rlhidu ngubi cing tdt cbn vbi ngubi su dimg thi cing duge tidp can vbi nhieu thbng tta thi cing tdt. Cac rtai eung cap dieh vu Truydn thbng hien tai rtaan thay van de niy vi citag ra sue td chQc eie he thdng nhim phue vu cho eie khich hing mgt each tdt rtaat, mbt mang nhu viy khbng thd chi li mbt mang Vidn thbng, mang tatemet hay mang truyen hinh dge lap ma a diy can phai Ii mang da dich vu hd ttg tat eie eie loai htah niy, cung cb the ggi day li mbt Mang the
he sau (NGN).
S U HOP NHAT CUA CAC M O I T R U O N G TRUYEN THONG
NhuYig life day cho sii hdp nhat
Ddi vbi cie mang cd dinh, mang PSTN vi ISDN ehu ydu eung cap dich vu thoai vi dieh vu tmydn htah. Nhimg nam gan diy, viec bimg nd cic thue bao vi nhu cau su dung tatemet. Ngubi dimg eb the su dung dubng tmydn tatemet ngiy cing cao, vl du dimg ADSL. Kdt ndi tatemet cho phep ngubi dimg su dung ei dieh vu ttao ddi theo thbi gian thuc:
chat, trb choi true tiep, VoIP.
Sir bimg no ve dau cuoi di dong: (sd lieu thdng ke thing 6 nam 2007, cb 3 ty diu cudi di dbng, ngubn Mobile World). Cic thidt hi niy tieh hgp sin nhidu til nguybn eho eie Qng dung. Cie dau cudi niy cb eac Qng dung lubn kdt ndi mang. Db li mbt su phit trien CO ban cua kha nang cung cap Qng dung.
Nhu cau tiao ddi thdng tin ngang hang: Cic img dung khbng cbn tdn tai rieng biet b cac thuc the ehl eb giao dien ttao ddi thbng tta vbi ngubi dimg mi cbn cb nhimg ttao ddi thbng tta ngang hing (peer-to-peer) vbi eae thuc the khae, vi du: chia se duybt weh. Do db, khii niem img dung can dugc dinh nghia lal kha nang kdt ndi: kha nang thidt lip ket ndi ngang hing dua tten cie thiet bi hd trg giao thuc IP. Day li yeu cau vi dbng lire chtah cho viec hgp rtaat giQa dau eudi dl dbng va dau eudi cd dirta nbi rieng, su hgp rtaat di dbng vi cd dtab b cic mat khie nbi chung.
TAP CHI CNTT&TT KY 1 (5.2010) 3 3
CONG NGHE V I E N THONG
Everything over IP
IP to and from Everywhere
IP over Everything
Hinh 2; Loi Ich cua viec IP hoa
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Hinh 3: Qua trinh phat trien cua dau cuoi
Cac giai doan hdp nhat
Truyen thong thdi ky tru'dc NGN
Tra lal rtaung nam 70-80 khi tatemet ehua phd bidn eic dieh vu tmyen thbng IQc db eb the thay rtau dien thoai (ed dirta, di dgng GSM, CDMA), phit tharta, tmyen htah quang bi, tmydn dQ heu nhu X25... vi chi mbt bb phan nhb ngubi din duge tiep xQe vbi eic dich vu niy. Vung phu cua eie dich vu rat han chd, dich vu don giin vi ehu ydu mbi phue vu cho cbng viec. Viec phuc vu eho giai tri cbn thieu thdn, neu mudn ngubi din phai den cic diem phuc vu tap tmng: rap chieu phim, rtai hit...
Thdi ky dau NGN
Trong thbi ky dau eua mang NGN diy cb the col li thbi ky IP hoi thue te li didn ra su hbi tu chuyen mach gbi vi chuyen mach kenh. Cic Qng dung tmydn thbng vdn duge thidt kd eho mang chuyen mach kbnh hay phit quang b i vb tuydn tmbe diy
dugc td chQc lai de boat dbng tten chuyen mach gbi:
Dich vu phat thanh: Tnrbc diy phat su dung eic bing tin AM, FM vi vimg phu hi gibi han eua vQng phu vb mydn bin kirta tQ vii chue ddn vii tram km.
Khi ehuyen sang mang IP dieh vu niy eb the phit di mgi noi tren the gibi midn li eb tatemet v i khbng can trang bi rihieu thiet hi cbng suat lbn.
Dich vu giii tri: Trabc day trlrta dien tip tnmg tai cac sin khau, rtai hat, rap, sin van dgng; ngiy nay cb the xem qua cie dieh vti VoD, khaeh hing eb thd xem tQ xa vi bien phbng a cua gia dtah thinh cic studio thuc su.
Dich vu thoai: Trabc day su dung he thdng chuyen mach kerta TDM vbi mgt mb htah phQc tap phan cap C3, C4, C5.. vi phien lien lac duge thiet lap duy tri trong sudt thbi gian thoai nen hieu suat thap vi gia thirta eao. Khi chuyen sang IP thi ludng dQ lieu duge chuyen thinh eie gbi kich thube xic dinh, dQng eac ky thuat ma hoi nbn lim giim yeu eau bang thbng nen hieu suat su dung tii nguyen cao, gii re.
Dich vu Traydn htah trabc diy su dung phit quang ba vb tuydn sau db Ii trayen hinh cable vi hien nay citag dugc ehuyen tal tren mang IP vbi ten mbi li IPTV. Vbi dieh vu niy khich hing khip noi tren tatemet cb the xem dugc vbi cae mQe chat lugng theo yeu eau.
Mbt diem ban ehd a giai doan niy li dQ cic dich vu tmydn thbng da duge IP hoi rtaimg xbt tren gbc do dieh vu thi chimg vin li cie de dao, chimg duge thidt kd dbc lap nhau: Cb he thdng dieu khien rieng, cb dau eudi rieng, giao thQc rieng vi he thdng quan
3 4 TAP CHi CNTT&TT KY 1 ( 5 . 2 0 1 0 )
Iy rieng. Didm hbi tu dat dugc b diy Ii ehimg ddu chay tten giao thuc IP, giao tauc IP cb the ehay tten vb sd eic giao thQe lbp dubi khie rtaau, cac phuang tien trayen tai vat ly khie rtaau (quang, dien). Vi vay ngubi ta ggi li "Every thtag over IP" vi "IP over every thtag".
Tien tdi sit hdp nhaft trong NGN
Trong thbi gian tbi xu the hgi tu giQa di dbng vi cd dinh tao cho vien thbng mbt bb mat mbi, diy li mang da dich vu rtaung khbng phai li eie dieh vu don le mi ehimg kdt hgp vbi rtaau su dung eie tii nguyen chung: Dau cudi. He thdng dieu khien, mang trayen tai...
Tren the he mang niy ngubi ta phin ra li eac nhbm
Coverage Hinh 4: Cac chuan tmyen thong
[ R F R M A C l EtlienietMAC
i B P R P H v l lOCbE LANPHV
lOGbE WAN PHY
Gb£
PHY
™
GFP
S O N E T ; SDH
zuz.
mG.709 OCh distal\vrapper./optK:alclia]mel
Op deal fibre / G.652, G.6S3 etc.
i c ] I ATM I
Hinh 5: Cac cong nghe tnjyen dan
Hinh 6: Kien true cua phan dieu khien
dieh vu: Hbi thoai (Convsrsation), ludng (sttsamtag), tuong tie (tatsraetive), ndn (background)., dd mang eb the bidt de phin biet eich ddi xu vbi cie loai luu lugng.
Diem khac biet so vbi gian doan trabc diy Ii Mang hbi tu (PMC) hubng den sQ dung mbt he thdng didu khien ehung eho mgi loai dieh vu xoi di bien gibi giua eie de dao lim cho don gian hoi ttong giao tidp vbi khich hing.
G I A I P H A P KY T H U A T
De thue hien theo ehien luge niy mbt sd giai phip sau duge dua ra:
Ve phia dau cudi
Thidt hi thbng mtah ban, hd ttg nhidu co chd tray rtaap, trinh didn (voles, vidso, van ban) tuong tu nhu mbt miy ttah xich tay...
Ve phia mang truy nhap:
- Su dung nhidu cbng nghs mbi nhim ting bing thbng chat lugng eic phien Uen lac:
• Mobile networks: 3G, 3.5G, WlMax, LTE
• Wired LAN: Ethemet, Fast Ethemet, Gigabit Ethemet
• WirelsssLAN: Ila/b, llg, 1 In
TAP CHI CNTT&TT KY 1 ( 5 . 2 0 1 0 )
I 35
CONG NGHE V I E N THONG
Hinh 7: Ha tang phat trien dich vu
• Fixsd Itas accsss nstworks: ADSL, ADSL2+, VDSL, VDSL2, EPON (Ethsmst PON, 0.6 hay I.25G), GPON (Gigabit Capable PON, 2.5G)
Ve phia m a n g t r u y e n t a i :
\/e phia he thdng dieu khien
Dd cic Qng dung tren ndn giao thuc IP trao ddi vbi rtaau, ehung ta can cb mbt ca ehd thieh hgp.
Mang thoai hien nay cung cap co chd niy li rat ban chd. Mudn thidt lap phien ket ndi ngang hing, mang thidt lap mbt ket ndi ad-hoe giQa hai dau eudi thbng qua mang IP. Han ehd kdt ndi IP niy chi dip Qng vbi rtaimg mbi trabng mbt nhi eung cap dieh vu tien tatemet, mbt he thdng dbng; tiao ddi giua cac rtai eung cap dieh vu.
Do db, chQng ta can mbt he thdng mang didu
^^'^(^^^ ^^z^Y;;:H'-r.^(s^r.
CP SP,
• • •
IMS
^
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Ltolti-access
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Hinh 8: Cac cong nghe tich hpp cho giai phap tdng the ciia NGN
khien da phuang tien tren ndn IP cb tirta toin eau, he thdng IMS [2]. IMS eho phbp cie Qng dung chay tren eie dau eudi hd trg giao thQc IP eb the dd ding thidt lap kdt ndi ngang hing diem-diem, hoac kdt ndi diem-nhi cung cap nbi dung (peer-to-eontent).
Su dung phin he IMS do 3GPP phat trien vi dugc bd sung bbi TISPAN ETSI vbi sd giao thue giam cbn vii 3 giao thQe nhung hieu nang eao vi hd trg nhieu dieh vu phQc tap
Ve he thong cung cap dich vu
De don gian vi nharta chbng eho viec phit trien eie dieh vu gia tang, ehimg ta cb giii phip dQng phan tu giao tidp phat trien dich vu (APP Gateway) nhu Parlay Gateway hay gan diy li SDP (Service DeUvery Platiorm). Cic he thdng niy hd trg eac Nhi eung cap ngi dung hoic Nhi eung cap dieh vu (VASP) phit trien vi eung cap dieh vu rtaanh chbng.
SDP cung hd ttg VASP trong viee quan ly eic CP.
Nhu vay, eie mbi trabng trayen thbng dang hbi tu
3 6 TAP CHI CNTT&TT KY 1 ( 5 . 2 0 1 0 )
tainh mang trayen thbng hgp nhat cho eic dieh vu khic rtaau, su dung eic ebng nghe Uch hgp.
T R I E N K H A I T A I V I E T N A M
Viet Nam li mbt trong itaitag nube eb toe do phit trien cao rtaat vd vien thbng trbn thd gibi do cie chuta sach ebi ma trong mang niy, vibe niy kso taeo sir phit trien eua ea so ha tang mang (CSHT).
Cic nhi khai thic mang b Viet Nam Uen tidp ra dbi vi tham gia vio thi trabng vbi eie trang hi gan nhu hien dai rtaat tren the gibi tao ra mgt su sbl dbng ciia su canh trarta vi dieu niy mang lai rihieu lgi ieh cho ngubi dimg.
Xu hubng hbi tu cung da htah thinh vi bit dau dugc thue hien tten thue td. Sir chuyen hba mb htah kirta doanh tten mang NGN da vi dang didn ra.
Hisn nay da xuat hisn cie Nhi khai thie di dbng ao (MVNO), eic CP ngoii tham gia vio kinh doanh dieh vu Vidn thbng ttong khi khbng cb co so ha tang tray nhip, day Ii bieu hien cua mb htah phan Ibp theo chieu ngang.
Nhidu nhi nhi khai thic lbn a VN da eb mbt lugng lbn khich hing trayen thdng vi so hiiu eie mang tmy nhip khie nhau, dd carta ttanh hg mong mudn cung cap nhieu dieh vu mbi cho khic hing vi hg da vi dang chu dbng ehia se viec phit tridn dieh vu gia
tang vbi CP, bin lai tii nguyen cho cie xVWO hay ehuyen viee cham sbe khich hing eho eie ebng ty ben ngoii ddng thbi da vi dang ed ging ma rbng vimg phu cua dieh vu, keo duge nhieu khich hing ban vi dam bao chat lugng phan ha tang dichvu
K E T L U A N
Mbi trabng trayen thbng da dieh vu li mong mudn cua eie nhi cung cap dieh vu rtaim eung cap eho khich hing cie dieh vu phong phQ vi tien tien nhat. Cie td ChQc chuan hba vi cic nhi nghien cQu dang tip trung nghien cQu vd cic van dd niy. Hien nay, su hgi tu giua chuydn mach ksrta vi ehuysn mach gbi citag rtau sir hbi tu ed dinh vbi di dgng li tidn dd thue day eho sir phit tridn rtaanh chbng cua cac cbng nghs/glai phip cb tinh tich hgp eao vi didn binh a diy li giai phap didu khien IMS vi nen tang phin phat ngi dung SDP eb kha nang hd ttg didu khien ehung cho mgi loai htah dich vu cung nhu Uen ket rtai cung cap nbi dung tao nen su da dang phong phu trong cie dieh vu gia tang tten nen mang vidn thbng mbi. Cie cbng nghe ndn tang tao nen mang IP cimg dang dugc hoan thien de tao nen mbi trabng bang rbng tray nhip quang den khich hing. Cie nhi khai thic vien thbng Ibn b Viet Nam nhu VNPT, Vletel.. dang tung bube tridn khai eic cbng nghs niy vio mang cua mtah.
Tai lieu t h a m l<hao:
[1]. MIIKKAPOIKSELKA.GEORG MAYER, HISHAMKHARTABIL, AKl NIEMI, "The /MS - IP t^uitimedia Concepts And Sen/ices In The IViobileDomain", NXB Wiley, 2004.
[2]. 3GPPTS 23.228, "IP!^ultimediaSi±isystem(msy', June 2008.
[3]. ETSI ES 2 8 2 0 0 1 , "NGN Functbnal Architecti^e", March 2008.
TAP CHI CNTT&TT KY 1 ( 5 . 2 0 1 0 ) | 3 7 '
