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), i-Optical Network Unit (ONU) kanye ne-Optical Distribution Network (ODN). Isici esibalulekile ukuthi i-ODN yonke yakhiwe izinto zokungenzi lutho, 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 kwendawo emaphakathi. Ihhovisi kanye neklayenti, kanye nomthombo wemishini kagesi iphakathi kwale nethiwekhi yokufinyelela.Ngaphezu kwezinzuzo zokulondoloza izinsiza ze-fiber, i-PON ingenza kube lula kakhulu ukusebenza nokugcinwa kwesistimu yenethiwekhi, ephumelela kakhulu ekwehliseni izindleko zokwakha nokusebenza.Ngaphezu kwalokho. , ukwakheka kwemidiya ye-optical ehlanzekile kanye nenethiwekhi ye-optical fibre broadband esobala iqinisekisa ukuvikeleka kwezobuchwepheshe kokukhula 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 i-Optical Line Terminal (OLT), i-Optical Network Unit (ONU) ehlangothini lomsebenzisi kanye ne-Optical Distribution Network (ODN).
2.1 OLT
Isikhathi esiningi, i-OLT ibekwa egumbini lomshini elimaphakathi.Inikeza izaba ze-fiber optical zenethiwekhi ye-passive optical eya phansi, i-GE, i-10baes-t, i-100base-t, i-10gbase-x nezinye izixhumi ezibonakalayo eziya phezulu, futhi i-OLT isekela isixhumi esibonakalayo se-EI ukuze ibone ukufinyelela kwezwi kwe-TDM.
2.2 ONU/ONT
I-ONU/ONT ibekwe ekugcineni komsebenzisi, ikakhulukazi kusetshenziswa iphrothokholi ye-Ethernet ukubona ukudluliswa okusobala kwedatha yomsebenzisi.Idatha ingadluliselwa phakathi kwe-OLT ne-ONU.
2.3 I-ODN
Njengegatsha le-fiber engenzi lutho, i-ODN ixhuma izinto ezisetshenziswayo ze-OLT ne-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 aliphezulu, ngakolunye uhlangothi, ukwabiwa komkhawulokudonsa oguquguqukayo kuzothuthukisa ukusetshenziswa komkhawulokudonsa wesistimu.Izidingo zesevisi engazelelwe ze-ONU kungenziwa yi-DBA.Ukulungiswa komkhawulokudonsa onamandla phakathi kwe-ONU kungathuthukisa ukusebenza kahle komkhawulokudonsa okhuphukayo 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 yeqa umkhawulokudonsa wendlela yokwabiwa kweyunifomu evamile.
Ukulawula okumaphakathi kuyindlela yokwabiwa komkhawulokudonsa oguquguqukayo.Le ndlela ingeyayo yonke imilayezo ye-ONU uplink, isetshenziswa ku-OLT ukuze uthole umkhawulokudonsa, bese i-OLT ngokwesicelo sokugunyazwa kwe-ONU ngokuhambisana ne-algorithm efanele ye-broadband ebalwa ku-W. Umbono oyisisekelo we-algorithm yenqubo yokwaba ukuthi i-ONU lee uplink ngayinye ingahlukanisa isikhathi sokufika kweseli futhi icele umkhawulokudonsa.Ngokwesicelo se-ONU ngayinye, i-OLT yabela umkhawulokudonsa ngendlela efanele nangendlela enengqondo, futhi isingatha ukucubungula ukugcwala, ikhodi yephutha lolwazi, iseli ukulahlekelwa, 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 lokuguquguquka kwesevisi lingabi namandla ngokwanele.I-ONU idinga ukuvumelanisa nezinye izindlela zokufinyelela okungahleliwe ngaphandle kwe- isikhathi esithile sokufinyelela.Ngakho-ke, ukuhlukaniswa kwesikhathi sezibalo ukuphindaphinda kokufinyelela okuningi ngokuvamile kusetshenziswa ngemva kokuqhathanisa ukushoda kokubili.Lapho isignali ye-uplink idluliswa, ifreyimu ye-Ethernet ithunyelwa ngesikhathi lapho i-ONU yabelwe khona, kanye nosayizi we idatha enikezwe ukuphindaphinda kwezibalo isetshenziselwa ukushintsha usayizi weslot yesikhathi.
3.3 Ubuchwepheshe besinxephezelo se-OLT obusukelayo nokubambezeleka kanye nobuchwepheshe bokuxhuma nokudlala be-ONU
Ngenxa yokuthi isiteshi esikhuphuka nomfula se-EPON ISEBENZISA i-TDMA, ukufinyelela kwamaphoyinti amaningi kwenza ukubambezeleka kohlaka lwedatha ye-ONU ngayinye kuhluke, ngakho ubuchwepheshe besinxephezelo obusukelayo nokubambezeleka kwethulwa ukuze kuvinjelwe ukushayisana kwedatha esizindeni sesikhathi.Ukuze kugwenywe ukushayisana kwesikhathi. idatha yesizinda, isilinganiso sebanga 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 nokudlala ku-ONU.Ukulinganisa ibanga ukusuka kuleyo naleyo. I-ONU iye ku-OLT ngokunembile futhi ukulungisa ukubambezeleka kokudlulisela kwe-ONU ngokunembile kunganciphisa isikhawu phakathi kokuthumela i-Windows ye-ONU, kuthuthukise ukusetshenziswa kwesiteshi se-uplink futhi kunciphise ukubambezeleka.Ukulinganisa kwe-EPON kuyaqalwa futhi kuqedwe ngesikhathi esifanayo lapho i-OLT idlula khona, ukumaka ngesikhathi esifanayo lapho kutholwa khona ipulaki nokudlala kwe-ONU.
3.4Ukuthumela nokwamukela izimpawu eziqhumayo
Njengoba isignali yokuqhuma ye-ONU ngayinye yamukelwa yi-OLT, i-OLT idinga ukubona ukuvumelanisa kwesigaba isikhathi esithile bese ithola idatha.Lokhu kudinga ukusetshenziswa kwamadivaysi okubona akwazi ukusekela amasignali okuqhuma ku-ONU naku-OLT.Iningi lemishini yokubona ayikwazi ukuhlangabezana lesi sidingo, kanye nenani elincane lemishini ye-optical mode yokuqhuma inesivinini sokusebenza esingaba ngu-155M, okuyinani eliphakeme kakhulu.Ngakho-ke, ukuze kubonakale imodi yokuqhuma ngokuphumelelayo, amasu akhethekile asetshenziselwa ukuphela kokuthola.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 kwamukelwa isignali entsha.
4.Ukusetshenziswa kokuxhumana kwe-fiber optic esitokisini
I-ONU ingasethwa ohlangothini lweklayenti (FTTH) noma emhubheni (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 i-optical splitter isethwe ngendlela efanayo ne-FTTH.Le ndlela yokufinyelela ngokuvamile yenziwa ekushintsheni komhubhe.
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 bezokuxhumana 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.