Njengendlela yokuxhumana ephumelelayo evame ukusetshenziswa. I-EPON isetshenziswa abasebenzisi ukuxhuma kunethiwekhi yokufinyelela.Kuleli phepha, ubuchwepheshe obuyinhloko be-EPON buchazwe kafushane, futhi ukusetshenziswa kwe-EPON ekuxhumaneni optical kwethulwa ngokuningiliziwe, futhi isimiso sayo sobuchwepheshe siyahlaziywa.
1.Iiisingenisokwe-EPON
I-PON isifinyezo se-Passive Optical Network, okuwubuchwepheshe bokufinyelela obubonakalayo obuthuthukiswe ukusekela izinhlelo zokusebenza ze-point-to-multipoint.I-PON iqukethe i-Optical Line Terminal (OLT), Iyunithi Yenethiwekhi Yokubona (I-ONU) kanye ne-Optical Distribution Network (ODN).Isici sayo esibalulekile ukuthi i-ODN yonke yenziwe ngamathuluzi angasebenzi, futhi isignali ihlakazwa isuka ku-Shared optical fiber eyodwa iye kumsebenzisi ngamunye ngokusebenzisa isihlukanisi.Lolu hlelo lubizwa ngokuthi i-Passive Optical Network ngoba yehlukile ekuxhumaneni okuvamile phakathi kwehhovisi elimaphakathi neklayenti, futhi umthombo wemishini kagesi uphakathi kwale nethiwekhi yokufinyelela.Ngaphezu kwezinzuzo zokulondoloza izinsiza ze-fibre, i-PON ingenza kube lula kakhulu ukusebenza nokugcinwa kwesistimu yenethiwekhi, ngempumelelo kakhulu ekunciphiseni izindleko zokwakha nokusebenza.Ngaphezu kwalokho, ukwakheka kwemidiya ye-optical ehlanzekile kanye nenethiwekhi ye-optical fiber broadband esobala iqinisekisa ukuvikeleka kwezobuchwepheshe kokwanda kwebhizinisi kwesikhathi esizayo.
Ubuchwepheshe be-EPON buhlanganisa ubuchwepheshe be-Ethernet nobuchwepheshe be-PON ukuze kutholakale ukufinyelela kwe-fiber ye-Ethernet ye-point-to-multipoint high-speed ngendlela elula.I-point-to-multipoint topology imodi yesakhiwo eyamukelwa yi-EPON, kuyilapho imodi yokusakaza isetshenziselwa i-downlink. futhi imodi ye-TDMA isetshenziselwa umugqa we-upline, ekwazi ukubona ukudluliswa kwedatha ngezindlela ezimbili.
2.Ukwakhiwa kwe-EPON
Njengobuchwepheshe bokufinyelela i-fiber point-to-multipoint, i-Passive Optical Network (PON) iqukethe Itheminali yendawo ye-Optical Line (OLT), Iyunithi yenethiwekhi ye-Optical ohlangothini lomsebenzisi (I-ONU) kanye ne-Optical Distribution Network (ODN).
2.1OLT
Isikhathi esiningi,OLTibekwe egumbini lomshini ophakathi. Inikeza izaba zefiber optical for passive optical network in the direction of downward, GE, 10baes-t, 100base-t, 10gbase-x nezinye izindlela zokuhlangana ezibheke phezulu, kanyeOLTisekela isixhumi esibonakalayo se-EI ukuze uthole ukufinyelela kwezwi kwe-TDM.
2.2I-ONU/ONT
I-ONU/ONT ibekwe ekugcineni komsebenzisi, ikakhulukazi kusetshenziswa umthetho olandelwayo we-Ethernet ukubona ukudluliswa okusobala kwedatha yomsebenzisi. Idatha ingadluliselwa phakathiOLTfuthiI-ONU.
2.3 I-ODN
Njengegatsha le-fiber engenzi lutho, i-ODN ixhuma izinto ezisetshenziswayo zeOLTfuthiI-ONU. Umsebenzi oyinhloko we-ODN ukusabalalisa idatha ye-downlink kanye nokubeka phakathi idatha ye-uplink.Ngenxa yokuthi kuwumsebenzi owenziwe, ukuthunyelwa kwe-splitter okwenziwayo kuvumelana nezimo kakhulu futhi kulungele izindawo eziningi.Ngomqondo ojwayelekile, i-POS ngayinye inesilinganiso sokuhlukaniswa esingu-8, 16, 32 noma 64, futhi ingaxhunywa emazingeni amaningi.
3.Iisingenisoof key tizibaloof EPON
3.1Dbasfor donamandlabkanye nobubanziaisabelo
Isikhathi sangempela (ms/us magnitude) sishintsha indlela yomkhawulokudonsa okhuphukayo we-OUN ngayinye ku-EPON, eyaziwa ngokuthi i-algorithm yokwabiwa komkhawulokudonsa oguquguqukayo.Ku-EPON, uma umkhawulokudonsa wabiwa ngokwezibalo, kusho ukuthi isevisi yezinga lokudlulisela lokuxhumana kwedatha ayifaneleki kakhulu.Uma umkhawulokudonsa wabiwa ngokwezibalo ngesivinini esiphezulu, wonke umkhawulokudonsa wesistimu uzophela ngesikhathi esifushane.Izinga le-W lomkhawulokudonsa alikho phezulu, ngakolunye uhlangothi, ukwabiwa komkhawulokudonsa oguquguqukayo kuzothuthukisa ukusetshenziswa komkhawulokudonsa wesistimu.Izidingo zesevisi ezisheshayo zeI-ONUkungenziwa yi-DBA. Ukulungiswa komkhawulokudonsa onamandla phakathiI-ONUingakwazi ukuthuthukisa ukusebenza kahle komkhawulokudonsa we-PON.Ngenxa yokuthuthukiswa kokusebenza kahle kokusetshenziswa komkhawulokudonsa, abasebenzisi abaningi be-W bangangezwa ku-PON ekhona, futhi inani eliphakeme lomkhawulokudonsa abasebenzisi baka-W abangafinyelela kulo lingaqhathaniswa noma lidlule umkhawulokudonsa indlela yendabuko yokwabiwa kweyunifomu.
Ukulawula okumaphakathi kuyindlela yokwabiwa komkhawulokudonsa.Le ndlela eyabo bonkeI-ONUuplink imilayezo, isetshenziswa kuOLTku-bandwidth, keOLTngokwesicelo seI-ONUukugunyazwa ngokuhambisana ne-algorithm efanelekile ye-broadband ebalwe ku-W. Umbono oyisisekelo we-algorithm yemibandela yokwaba ukuthi i-ONU lee uplink ngayinye ingahlukanisa isikhathi sokusabalalisa kokufika kweseli futhi icele umkhawulokudonsa.Ngokwesicelo somuntu ngamunyeI-ONU, OLTyabela umkhawulokudonsa ngendlela efanele nangendlela enengqondo, futhi isingatha ukucubungula ukugcwala, ikhodi yephutha lolwazi, ukulahleka kweseli, njll.
3.2Phinda usebenzise ubuchwepheshe besiteshi se-uplink
Njengamanje, ukuqaliswa okuyinhloko ukuhlukaniswa kwesikhathi kwe-multiple access multiplexing (TDMA), engasetshenziswa ngesikhathi esifanayo se-slot time division multiplexing, ukuhlukaniswa kwesikhathi sezibalo ukuphindaphinda kokufinyelela okuningi, ukufinyelela okungahleliwe nokunye.Nokho, i-M - isikhathi - isikhathi se-slot. - ukuphindaphindeka kwe-division kunezinye iziphambeko.Isibonelo, uma ezinye zezikhathi ezibekiwe zingasetshenziswa, kuthatha umkhawulokudonsa othize, ukuze izinga eliphezulu lokuqhuma kwesevisi likwazi ukuzivumelanisa nezimo lingabi namandla ngokwanele.I-ONUidinga ukuvumelanisa nezinye izindlela zokufinyelela okungahleliwe ngaphandle kwesikhathi esithile sokufinyelela.Ngakho-ke, ukuhlukaniswa kwesikhathi sezibalo ukuphindaphinda kokufinyelela okuningi ngokuvamile kusetshenziswa ngemva kokuqhathanisa ukushoda kwakho kokubili.Lapho isignali ye-uplink idluliselwa, ifreyimu ye-Ethernet ithunyelwa ngesikhathi lapho iI-ONUinikezwe, futhi usayizi wedatha onikezwe ukuphindaphinda kwezibalo usetshenziselwa ukushintsha usayizi weslot yesikhathi.
3.3 OLT sika esukela kanye ukubambezeleka isinxephezelo ubuchwepheshe kanyeI-ONUubuchwepheshe be-plug-and-play
Ngenxa yokuthi isiteshi esikhuphukayo se-EPON ISEBENZISA i-TDMA, ukufinyelela kwamaphoyinti amaningi kwenza ukubambezeleka kohlaka lwedatha ngakunyeI-ONUokuhlukile, ngakho ubuchwepheshe besinxephezelo esisukela nokubambezeleka kwethulwa ukuze kuvinjelwe ukungqubuzana kwedatha esizindeni sesikhathi.Ukuze kugwenywe ukungqubuzana kwedatha yesizinda sesikhathi, ukukalwa kwebanga kanye nobuchwepheshe besinxephezelo sokulibaziseka kwesikhathi kufanele kusetshenziselwe ukuvumelanisa lonke igebe lesikhathi senethiwekhi. Ngale ndlela, amaphakethe afika endaweni yesikhathi esinqunyiwe ngokuya nge-algorithm ye-DBA kanye nepulaki yokusekela nokudlalaI-ONU.Ukulinganisa ibanga ukusuka ngakunyeI-ONUto OLTngokunembile kanye nokulungisa ukubambezeleka kokudlulisela kweI-ONUngokunembile kunganciphisa isikhawu phakathi kokuthumela iWindows yeI-ONU, thuthukisa ukusetshenziswa kweshaneli ye-uplink futhi unciphise ukubambezeleka. Ukulinganisa kwe-EPON kuyaqalwa futhi kuqedwe ngesikhathi esifanayo laphoOLTUkudlula, ukumaka ngesikhathi esifanayo lapho ipulaki nokudlala kweI-ONUitholakele.
3.4Ukuthumela nokwamukela izimpawu eziqhumayo
Kusukela isignali kuqhuma ngamunyeI-ONUyamukelwe nguOLT, OLTidinga ukubona ukuvumelanisa kwesigaba isikhathi esithile bese ithola idatha.Lokhu kudinga ukusetshenziswa kwezinto ezibonakalayo ezikwazi ukusekela amasignali okuqhumaI-ONUfuthiOLT.Imishini eminingi yokubona ayikwazi ukuhlangabezana nalesi sidingo, futhi inombolo encane yemishini yokubona yokuqhuma inesivinini sokusebenza esingaba ngu-155M, okuyinani eliphakeme kakhulu uma kuqhathaniswa. ukuphela kokwamukela. I-optical burst transmission circuit idinga ukuvala nokuvula ngokushesha okukhulu futhi isungule amasignali ngokushesha.Ngakho-ke, imojula yendabuko yokuguqula i-electro-optical esebenzisa ukulawulwa kwamandla okuzenzakalelayo ngempendulo ayisafanele ukusetshenziswa, kodwa idinga ama-lasers anempendulo esheshayo. eyamukelayo ithola isignali amandla okukhanya komsebenzisi ngamunye ihlukile futhi variable nakakhulu. Ngakho-ke, kumjikelezo wokwamukela okuqhume, izinga lokwamukela (umbundu) lidinga ukulungiswa njalo lapho isignali entsha itholwa.
4.Ukusetshenziswa kokuxhumana kwe-fiber optic esitokisini
II-ONUingasethwa ohlangothini lweklayenti (FTTH) noma ephasishini (FTTB), kodwa lokhu kusesimweni samaseli okufinyelela.Kumodi ye-FTTH, inani labasebenzisi aliqinisekile. Kulesi simo, ukuze kuthuthukiswe izinga lokusetshenziswa kwemishini, ukunciphisa izindleko futhi kube lula ukugcinwa.Ukusetha kwe-optical divider kugxile ngokuqhathaniswa, kanye nokusetshenziswa kwezinga lokusabalalisa ukukhanya, ukusetha indawo yezinto eziningi kukhompyutha. igumbi lomphakathi noma lomphakathi ngaphakathi kwebhokisi lokunikeza ukukhanya. Ngemuva kokwakhiwa ngendlela enjalo, kungakhathaliseki ukuthi inani labasebenzisi likhuphuka noma liyancipha, ukusetshenziswa kwemishini kungakhuliswa. Kodwa-ke, uma inani labasebenzisi likhulu, isidingo sokufinyelela ku-fiber optical naso sizokhula kakhulu.Ngenkathi ikumodi ye-FTTB, i-OMU isethwe emhubheni, futhi isihlukanisi se-optical sisethwe ngendlela efanayo ne-FTTH. Le ndlela yokufinyelela ngokuvamile yenziwa ephasejishintsha.
Isiphetho
Ubuchwepheshe be-EPON bunezinzuzo eziningi, njengokufakwa okubanzi kwabasebenzisi, isivinini esikhulu sokukhuphuka nomfula, izici zokudlulisa amehlo ezisebenza kahle, ukonga izinsiza ze-fibre ukusuka endaweni kuya kunethiwekhi yamaphuzu amaningi nokunye.Ngedatha yezwi, i-video enezinsiza eziningi kanye nenkampani yenethiwekhi. -Izinga lokusebenza liqokwe izakhiwo zobuchwepheshe, kodwa futhi linezimo, azikho izici zokonga amandla emisebe kagesi kanye nezici zokuvikela imvelo.Njengobuchwepheshe bokuxhumana obubonakalayo, ubuchwepheshe be-EPON bubaluleke kakhulu.Njengobunye bobuchwepheshe obujwayelekile esikhathini esizayo, ubuchwepheshe be-EPON bunezici. lokuzivumelanisa nezimo eziqinile endaweni yokuthunyelwa, ukwethembeka okuphezulu kanye nokungakhathalelwa, kube yisinqumo esingcono kakhulu sokwakhiwa kwenethiwekhi yokufinyelela ye-broadband yesizukulwane esilandelayo.