Njengendlela yonxibelelwano esebenzayo esoloko isetyenziswa. I-EPON isetyenziswe ngabasebenzisi ukuxhuma kwinethiwekhi yokufikelela.Kulo phepha, iteknoloji ephambili ye-EPON ichazwe ngokufutshane, kwaye ukusetyenziswa kwe-EPON kunxibelelwano lwe-optical kwaziswa ngokubanzi, kwaye umgaqo wayo wobugcisa uhlalutywa.
1.Iiintshayeleloye EPON
I-PON yi-contraction ye-Passive Optical Network, eyi-teknoloji yokufikelela kwi-optical eyenzelwe ukuxhasa izicelo ze-point-to-multipoint.I-PON iqulethe i-Optical Line Terminal (OLT), iYunithi yeNethiwekhi yokubona (I-ONU) kunye neNethiwekhi ye-Optical Distribution Network (ODN) .Isici sayo esibalulekileyo kukuba i-ODN yonke iqulunqwe ngezixhobo zokwenziwa, kwaye umqondiso usasazwa kwi-fiber eyodwa ekwabelwana ngayo kumsebenzisi ngamnye ngokuqhekeza.Le nkqubo ibizwa ngokuba yi-Passive Optical Network ngenxa yokuba yahlukile kunxibelelwano lwemveli phakathi kweofisi esembindini kunye nomxhasi, kunye nomthombo izixhobo zombane ziphakathi kolu fikelelo lwenethiwekhi.Ukongezelela kwiingenelo zokugcina izibonelelo zefiber, iPON ingenza lula kakhulu ukusebenza kunye nokugcinwa kwenkqubo yothungelwano. ngempumelelo kakhulu ekunciphiseni iindleko zokwakha kunye nokusebenza.Ngaphezu koko, isakhiwo seendaba ezicocekileyo ze-optical media kunye ne-transparent optical fiber broadband network iqinisekisa ukhuseleko lobugcisa bokwandiswa kweshishini elizayo.
Iteknoloji ye-EPON idibanisa iteknoloji ye-Ethernet kunye neteknoloji ye-PON ukuqonda i-point-to-multipoint high-speed Ethernet fiber access ngendlela elula.I-point-to-multipoint topology yindlela yesakhiwo esamkelwe yi-EPON, ngelixa imodi yosasazo isetyenziselwa i-downlink. kunye nemowudi ye-TDMA isetyenziselwa umgca, onokuqonda ukuhanjiswa kwedatha ngeendlela ezimbini.
2.Ukwenziwa kweEPON
Njengobuchwephesha bokufikelela kwi-fiber point-to-multipoint, i-Passive Optical Network (PON) iqukethe i-Optical Line Terminal yendawo (OLT), iYunithi yeNethiwekhi yeOptical kwicala lomsebenzisi (I-ONU) kunye ne-Optical Distribution Network (ODN).
2.1OLT
Ngamaxesha amaninzi,OLTibekwe kwigumbi eliphakathi koomatshini. Ibonelela ngesizathu se-fiber optical network ye-passive optical kwicala eliya ezantsi, i-GE, i-10baes-t, i-100base-t, i-10gbase-x kunye nolunye ujongano oluya phezulu, kunyeOLTixhasa ujongano lwe-EI ukuqonda ukufikelela kwilizwi le-TDM.
2.2I-ONU/ONT
I-ONU/ONT ibekwe kwisiphelo somsebenzisi, ikakhulu kusetyenziswa i-Ethernet protocol ukuqonda ukuhanjiswa okucacileyo kwedatha yomsebenzisi. Idatha ingathunyelwa phakathiOLTkwayeI-ONU.
2.3 ODN
Njengesebe le-fiber ye-passive, i-ODN idibanisa izixhobo ze-passive zeOLTkwayeI-ONU. Umsebenzi oyintloko we-ODN kukusabalalisa idatha ye-downlink kunye ne-centralise data ye-uplink.Ngenxa yokuba i-passive operation, i-passive splitter deployment iguquguquka kakhulu kwaye ifanelekile kwiindawo ezininzi.Ngokwengqiqo eqhelekileyo, i-POS nganye inezinga lokuhlukana kwe-8, i-16, i-32 okanye i-64, kwaye inokudityaniswa kumanqanaba amaninzi.
3.Iintshayeleloof key tubugcisaof EPON
3.1Dbasfor dngamandlabnobubanziaulwabiwo
Ixesha langempela (ms/us magnitude) litshintsha i-uplinking bandwidth mechanism ye-OUN nganye kwi-EPON, eyaziwa ngokuba yi-algorithm yolwabiwo lwe-bandwidth.Kwi-EPON, ukuba i-bandwidth yabelwe ngokwezibalo, ngoko ke inkonzo yesantya sothumelo lonxibelelwano lwedatha ayifanelekanga kakhulu. i-bandwidth yabelwe i-statically kwi-peak speed, yonke i-bandwidth yenkqubo iya kuphelelwa ngexesha elifutshane.Izinga le-W bandwidth aliphezulu, kwelinye icala, ulwabiwo lwe-bandwidth oluguqukileyo luya kuphucula ukusetyenziswa kwe-bandwidth yenkqubo.I-ONUinokuphunyezwa yi-DBA. Uhlengahlengiso lwebhanwidth enamandla phakathiI-ONUNgenxa yokuphuculwa kokusetyenziswa kwe-bandwidth esebenzayo, abasebenzisi abaninzi be-W banokongezwa kwi-PON ekhoyo, kunye nexabiso lencopho ye-bandwidth abasebenzisi be-W abanokufikelela kuyo banokuthelekiswa okanye bagqithise umda we-bandwidth indlela yokwabiwa kweyunifomu yemveli.
Ulawulo olusembindini yindlela yolwabiwo lwebhanwidth eguquguqukayo.Le ndlela yeyazo zonkeI-ONUimiyalezo ye-uplink, isetyenziswa kwiOLTkwi-bandwidth, ngokoOLTngokwesicelo seNkosiI-ONUugunyaziso ngokuhambelana ne-algorithm efanelekileyo ye-broadband echazwe kwi-W.Ingcamango esisiseko ye-algorithm yolwabiwo lwekhrayitheriya kukuba i-ONU lee uplink nganye inokwahlula ukuhanjiswa kwexesha lokufika kweseli kunye nokucela i-bandwidth.Ngokwesicelo somntu ngamnye.I-ONU, OLTyabela i-bandwidth ngokufanelekileyo nangengqiqo, kwaye iphatha ukulayisha ngaphezulu, ikhowudi yempazamo yolwazi, ilahleko yeeseli, njl.
3.2Phinda usebenzise itekhnoloji yesitishi se-uplink
Okwangoku, ukuphunyezwa okuphambili kuluhlu lwexesha lokuphindaphinda ukufikelela kwi-multiplexing (TDMA), enokusetyenziswa ngexesha elifanayo le-slot time division multiplexing, i-statistical time division multiplexing access multiplexing, access random and so on.Nangona kunjalo, M - ixesha - ixesha le-slot. Umzekelo, xa ezinye zeendawo zokubeka zingasetyenziswanga, zithatha i-bandwidth ethile, ukwenzela ukuba ukulungelelaniswa kwenkonzo yokuqhuma okuphezulu akunamandla ngokwaneleyo.I-ONUidinga ungqamaniso kunye nezinye iindlela zokufikelela ngokungaqhelekanga ngaphandle kwexesha elithile lokufikelela.Ngoko ke, ulwahlulo lwexesha lezibalo ulwahlulo lwe-multiplexing lusetyenziswa ngokuqhelekileyo emva kokuthelekisa ukunqongophala kwezi zibini.Xa isignali ye-uplink ihanjiswa, isakhelo se-Ethernet sithunyelwa kwixesha lokungena apho. iI-ONUyabelwe, kwaye ubungakanani bedatha enikezelwe yi-statistical multiplexing isetyenziselwa ukutshintsha ubungakanani bexesha eliqingqiweyo.
3.3 OLT's ukusuka kunye nokulibazisa imbuyekezo iteknoloji kunyeI-ONUiteknoloji yeplug-and-play
Ngenxa yokuba umjelo onyukayo we-EPON USEBENZISA i-TDMA, ukufikelela kwiindawo ezininzi kwenza ukulibaziseka kwesakhelo sedatha nganyeI-ONUezahlukeneyo, ngoko iteknoloji yembuyekezo yokusukela kunye nokulibaziseka iqaliswe ukunqanda ukungqubana kwedatha kwi-domain yexesha.Ukuze kuthintelwe ukungqubana kwedatha yendawo yexesha, umlinganiselo womgama kunye nobuchwepheshe bembuyekezo yexesha lokulibaziseka kufuneka kusetyenziswe ukuvumelanisa yonke isithuba sexesha lothungelwano. Ngale ndlela, iipakethi zifika ngexesha elichaziweyo ngokwe-algorithm ye-DBA kunye neplagi yenkxaso kunye nokudlala.I-ONU.Ukulinganisa umgama ukusuka kwindawo nganyeI-ONUto OLTngokuchanekileyo kunye nokulungelelanisa ulibaziseko losasazo lweI-ONUngokuchanekileyo kunokunciphisa isithuba phakathi kokuthumela iiWindows zeI-ONU, ukuphucula ukusetyenziswa kwetshaneli ye-uplink kunye nokunciphisa ukulibaziseka. Uluhlu lwe-EPON luqalisiwe kwaye lugqitywe ngexesha elifanayoOLTidlula, iphawula ngexesha elifanayo ukuba iplagi kunye nomdlalo weI-ONUibhaqwe.
3.4Ukuthumela kunye nokufumana iimpawu ezigqabhukileyo
Ekubeni ugqabhuko umqondiso ngamnyeI-ONUyamkelwa nguOLT, OLTidinga ukuqonda ungqamaniso lwesigaba kwithuba lexesha kwaye emva koko ufumane idatha.Oku kufuna ukusetyenziswa kwezixhobo ezibonakalayo ezikwaziyo ukuxhasa imiqondiso yokugqabhukaI-ONUkwayeOLTUninzi lwezixhobo zamehlo azikwazi ukuhlangabezana nale mfuno, kwaye inani elincinci lezixhobo ze-optical mode zinesantya sokusebenza malunga ne-155M, elixabiso eliphezulu kakhulu. isiphelo sokufumana. I-optical burst transmission circuit kufuneka ikwazi ukuvala kwaye ivule ngokukhawuleza kwaye imise izibonakaliso ngokukhawuleza.Ngoko ke, imodyuli yokuguqula i-electro-optical yendabuko usebenzisa ulawulo lwamandla oluzenzekelayo kunye nengxelo ayisafanelekanga ukusetyenziswa, kodwa ifuna i-lasers ngempendulo ekhawulezayo. isiphelo sokufumana sifumana isiginali yokukhanya amandla omsebenzisi ngamnye yahlukile kwaye iyaguquguquka ngakumbi. Ngoko ke, kwisekethe yokufumana ukuqhuma, inqanaba lokufumana (umqobo) kufuneka lilungiswe rhoqo xa kufunyanwa isiginali entsha.
4.Ukusetyenziswa konxibelelwano lwefiber optic kwiseli
II-ONUingacwangciswa kwicala lomxhasi (FTTH) okanye kwipaseji (FTTB), kodwa oku kwimeko yeeseli zofikelelo.Kwimo ye-FTTH, inani labasebenzisi aliqinisekanga. Kule meko, ukwenzela ukuba kuphuculwe izinga lokusetyenziswa kwezixhobo, ukunciphisa iindleko kunye nokuququzelela ukugcinwa.Ukumiselwa kwe-optical divider kugxininiswe ngokulinganayo, kunye nokusetyenziswa kwenqanaba lokusabalalisa ukukhanya, ukusetwa kwendawo yezinto ezininzi kwikhompyutheni. igumbi loluntu okanye loluntu ngaphakathi kwibhokisi yonikezelo olukhanyayo. Emva kokwakhiwa ngendlela enjalo, kungakhathaliseki ukuba inani labasebenzisi landa okanye liyancipha, ukusetyenziswa kwezixhobo kunokunyuswa. Nangona kunjalo, xa inani labasebenzisi likhulu, imfuno yokufikelela kwi-fiber optical iya kwandisa kakhulu.Ngeli xesha kwimodi ye-FTTB, i-OMU ibekwe kwi-corridor, kwaye i-optical splitter ibekwe ngendlela efanayo ne-FTTH. Le ndlela yokufikelela ngokuqhelekileyo iqhutyelwa kwi-corridortshintsha.
Ukuqukumbela
Itekhnoloji ye-EPON ineenzuzo ezininzi, ezifana nokugubungela ngokubanzi kwabasebenzisi, isantya esiphezulu sokunyuka nokwehla, iimpawu zokuhanjiswa kwe-optical ezisebenzayo, ukonga izixhobo zefiber ukusuka kwindawo ukuya kwi-multi-point networking njalo njalo.Ngedatha yelizwi, ividiyo eneenkonzo ezininzi kunye nomphathiswa. -Umsebenzi wenqanaba elichongiweyo loyilo lobugcisa, kodwa likwane-passive, akukho ugcino lwamandla emitha ye-electromagnetic kunye neempawu zokhuselo lokusingqongileyo.Njengetekhnoloji yonxibelelwano olubonakalayo, itekhnoloji ye-EPON ibaluleke kakhulu.Njengenye yeetekhnoloji eziphambili kwixesha elizayo, itekhnoloji yeEPON ineempawu ukuguquguquka okuqinileyo kwimeko yokusasazwa, ukuthembeka okuphezulu kunye nokugcinwa ngaphandle kokugcinwa, kuba lolona khetho lungcono kulwakhiwo lwesizukulwana esilandelayo sothungelwano lokufikelela kwibroadband.