EPON thiab GPON muaj lawv tus kheej zoo. Los ntawm qhov Performance index, GPON yog superior rau EPON, tab sis EPON muaj qhov zoo ntawm lub sij hawm thiab nqi. GPON tab tom ntes. Saib rau pem hauv ntej mus rau yav tom ntej broadband nkag lag luam, tej zaum nws yuav tsis yog leej twg hloov leej twg, nws yuav tsum tau coexisting thiab complementary. Rau bandwidth, ntau qhov kev pabcuam, siab QoS thiab kev ruaj ntseg, thiab cov neeg siv khoom nrog ATM thev naus laus zis raws li lub pob txha caj qaum, GPON yuav tsim nyog dua. Rau tus nqi-rhiab heev, QoS, thiab cov pab pawg neeg siv kev ruaj ntseg qis, EPON tau dhau los ua tus tseem ceeb.
PON yog dab tsi?
Kev siv thev naus laus zis dav dav tau nce zuj zus, lub hom phiaj los ua kev sib ntaus sib tua uas cov pa luam yeeb yuav tsis ploj mus. Tam sim no, cov khoom siv hauv tsev tseem yog ADSL thev naus laus zis, tab sis ntau thiab ntau cov khoom lag luam thiab cov tswv lag luam tau tig lawv lub ntsej muag rau optical network access technology.
Cov nqi tooj liab txuas ntxiv nce ntxiv, cov nqi kho qhov muag txuas ntxiv poob, thiab qhov kev thov loj hlob ntawm kev siv bandwidth los ntawm IPTV thiab cov kev pabcuam video game tsav kev txhim kho FTTH. Qhov ci ntsa iab ntawm kev hloov tooj liab thiab xaim coaxial cables nrog optical cables, xov tooj, cable TV, thiab broadband cov ntaub ntawv triplet ua kom pom tseeb.
PON (Passive OpTIcal Network) passive optical network yog lub ntsiab thev naus laus zis kom ua tiav FTTH fiber ntau rau hauv tsev, muab kev nkag mus rau point-to-multipoint fiber ntau. Raws li pom hauv daim duab 1, nws muaj covOLT(optical kab davhlau ya nyob twg) ntawm lub chaw ua haujlwm sab thiab cov neeg siv sab UasONU(Optical Network Unit) thiab ODN (Optical Distribution Network). Feem ntau, cov dej ntws qis siv TDM tshaj tawm thiab cov dej ntws siv TDMA (Lub Sijhawm Division Multiple Access) los ua ib qho point-to-multipoint tree topology. PON, raws li qhov loj tshaj plaws ci qhov chaw ntawm optical access technology, yog "passive". ODN tsis muaj cov khoom siv hluav taws xob thiab cov khoom siv hluav taws xob hluav taws xob. Tag nrho cov ntawm lawv yog tsim los ntawm passive li xws li optical splitters (Splitter). Kev tswj hwm, kev saib xyuas thiab kev ua haujlwm raug nqi qis.
Cov yam ntxwv ntawm EPON thiab GPON
EPON lub hom phiaj kom ua tau raws li Ethernet technology tam sim no. Nws yog qhov txuas ntxiv ntawm 802.3 raws tu qauv ntawm kev siv kho qhov muag network. Nws tau txais txiaj ntsig zoo ntawm cov nqi qis Ethernet, cov txheej txheem hloov tau yooj yim, thiab cov thev naus laus zis paub tab. Nws muaj kev lag luam dav thiab zoo sib xws. GPON yog nyob rau hauv kev lag luam kev sib txuas lus rau cov kev xav tau ntawm ntau qhov kev pabcuam, kev pabcuam puv ntoob nrog QoS lav, thiab sib zog nrhiav kev pom zoo uas txhawb nqa txhua qhov kev pabcuam thiab muaj kev ua haujlwm siab tshaj plaws, thov "qhib thiab ua tiav kev txiav txim siab ntawm txhua qhov kev pom zoo qhib. ”.
Cov yam ntxwv ntawm EPON yog raws li nram no:
1) Ethernet yog tus xa khoom zoo tshaj plaws rau nqa cov kev pabcuam IP;
2) Kev saib xyuas yooj yim, nthuav dav, yooj yim hloov kho;
3) EPON cov cuab yeej yog paub tab thiab muaj. EPON tau tso ntau lab kab hauv Asia. Cov chips lag luam thib peb tau raug tso tawm. Tus nqi ntawm cov khoom siv kho qhov muag muaj feem xyuam nrog cov khoom siv kho qhov muag thiab cov chips tau poob qis, mus txog qhov ntsuas ntawm kev lag luam siv, uas tuaj yeem ua tau raws li cov kev xav tau ntawm kev lag luam broadband tsis ntev los no;
4) EPON raws tu qauv yog yooj yim thiab tus nqi ntawm kev siv yog tsawg, thiab tus nqi ntawm cov khoom siv tsawg. Cov cuab yeej tsim nyog tshaj plaws yog xav tau nyob rau hauv kev nkag mus hauv metro, tsis yog qhov zoo tshaj plaws technology;
5) Ntau qhov tsim nyog rau thaj chaw hauv nroog, thaj chaw hauv nroog tsis muaj ATM lossis BPON cov khoom siv lub nra;
6) Tsim nyog rau yav tom ntej, IP nqa tag nrho cov kev pabcuam, thiab Ethernet nqa cov kev pabcuam IP.
Cov yam ntxwv ntawm GPON yog raws li nram no:
1) Nkag mus rau network rau kev lag luam hauv xov tooj;
2) High bandwidth: kab tus nqi, downstream 2.488Gb / s, ntws 1.244Gb / s; 3) Kev sib kis tau zoo: tus cwj pwm qis dua 94% (qhov tseeb bandwidth txog 2.4G) tus cwj pwm sab saud 93% (qhov tseeb bandwidth txog 1.1G);
3) Kev txhawb nqa kev pabcuam tag nrho: G.984.X tus qauv nruj me ntsis hais txog kev txhawb nqa ntawm cov nqa-qib cov kev pabcuam tag nrho (lub suab, cov ntaub ntawv thiab video);
4) Muaj peev xwm tswj tau zoo: nrog kev ua haujlwm nplua nuj, OAM domain txaus yog tshwj tseg hauv cov qauv qauv, thiab OMCI cov qauv raug tsim;
5) Kev pabcuam zoo: ntau qib QoS tuaj yeem lav qhov bandwidth thiab ncua sijhawm ntawm kev lag luam;
6) Tus nqi qis: Kev sib kis ntev thiab kev sib faib siab, uas ua rau muaj txiaj ntsig zooOLTcov nqi thiab txo cov nqi nkag rau cov neeg siv.
Qhov twg zoo dua, EPON vs GPON?
1. Cov qauv siv los ntawm EPON thiab GPON yog txawv. Nws tuaj yeem hais tias GPON yog qib siab dua thiab tuaj yeem xa cov bandwidth ntau dua, thiab tuaj yeem nqa cov neeg siv ntau dua li EPON. GPON pib los ntawm thaum ntxov APON \ BPON thev naus laus zis ntawm kev sib txuas lus fiber ntau, uas tau tsim los ntawm qhov no. ATM thav duab hom yog siv los xa cov lej kwj. E ntawm EPON yog hais txog kev sib txuas ntawm Ethernet, yog li thaum pib ntawm EPON yug, nws yuav tsum muaj peev xwm ncaj qha thiab seamlessly txuas nrog Is Taws Nem, yog li cov cai kwj ntawm EPON yog cov qauv ntawm Ethernet. Tau kawg, txhawm rau hloov kho kom haum rau kev sib kis ntawm fiber ntau optical, thav duab hom uas txhais los ntawm EPON yog qhwv sab nraum tus ncej ntawm Ethernet thav duab hom.
2. Tus qauv EPON yog IEEE 802.3ah. Lub hauv paus ntsiab lus ntawm IEEE los tsim tus qauv EPON yog ua qauv EPON nyob rau hauv 802.3 architecture kom ntau li ntau tau, thiab nthuav MAC raws tu qauv ntawm tus qauv Ethernet mus rau qhov tsawg kawg nkaus.
3. Tus qauv GPON yog ITU-TG.984 series ntawm cov qauv. Kev tsim qauv ntawm GPON tus qauv coj mus rau hauv tus account kev txhawb nqa rau cov kev pabcuam TDM ib txwm muaj thiab txuas ntxiv siv 125ms thav duab thav duab kom tswj tau 8K lub sijhawm txuas ntxiv. Txhawm rau txhawb nqa ntau txoj cai xws li ATM, GPON txhais cov qauv tshiab encapsulation GEM: GPONEncapsulaTionMethod. Cov ntaub ntawv ntawm ATM thiab lwm yam kev cai tuaj yeem muab sib xyaw thiab ntim rau hauv cov thav ntawv.
4. Nyob rau hauv cov nqe lus ntawm daim ntawv thov, GPON muaj ib tug loj bandwidth tshaj EPON, nws cov kev pab cuam bearer yog ntau npaum, thiab nws optical splitting peev xwm muaj zog dua. Nws tuaj yeem xa cov kev pabcuam bandwidth loj dua, paub ntau tus neeg siv nkag, them nyiaj ntau rau ntau qhov kev pabcuam thiab QoS lav, tab sis ua tiav ntau dua Nws nyuaj, uas ua rau nws cov nqi qis dua li ntawm EPON, tab sis nrog kev xa tawm loj. ntawm GPON technology, tus nqi sib txawv ntawm GPON thiab EPON yog maj mam nqaim.