Cibiyar sadarwa ta EPON tana amfani da hanyar FTTB don samar da hanyar sadarwa, kuma rukunin cibiyar sadarwarta na asali suneOLTda ONU.OLT yana ba da wadatattun tashoshin PON don kayan aikin ofishin tsakiya don haɗawa da kayan aikin ONU; ONU shine kayan aikin mai amfani don samar da daidaitattun bayanai da musanyawan murya don gane damar sabis na mai amfani.Ganewar samun dama ga ayyuka daban-daban shine galibi don amfani da alamun VLAN daban-daban don masu amfani daban-daban da ayyuka daban-daban don watsawa a zahiri zuwa uwar garken samun damar sabis, da aika madaidaitan alamun VLAN zuwa cibiyar sadarwar IP mai ɗaukar hoto don watsawa.
1. Gabatarwa zuwa EPON Network
EPON (Ethernet Passive Optical Network) fasaha ce ta hanyar sadarwa ta hanyar sadarwa ta fiber, wacce ke ɗaukar tsari-zuwa-multipoint, yanayin watsa fiber na gani mai ƙarfi, dangane da babban dandamalin Ethernet mai sauri da Rarraba lokacin MAC (MediaAccessControl) yanayin sarrafa hanyar watsa labarai. , Samar da fasahar samun damar watsa shirye-shirye don ayyuka daban-daban na haɗin gwiwar. Abin da ake kira "passive" yana nufin cewa ODN ba ta ƙunshi kowane na'urorin lantarki masu aiki da wutar lantarki ba, kuma gaba ɗaya ya ƙunshi na'urori masu mahimmanci kamar masu rarraba gani (Splitter).Yana amfani da fasahar PON a Layer na zahiri, ka'idar Ethernet a layin haɗin gwiwa, kuma yana amfani da topology PON don samun damar Ethernet.Sabili da haka, yana haɗuwa da fa'idodin fasaha na PON da fasahar Ethernet: ƙananan farashi, babban bandwidth, haɓaka mai ƙarfi, daidaitawa da sake tsara sabis na sauri, dacewa tare da Ethernet data kasance, gudanarwa mai dacewa, da sauransu.
EPON na iya gane haɗin murya, bayanai, bidiyo, da sabis na wayar hannu.Tsarin EPON yafi hada daOLT(Tsarin layin na gani), ONU (naúrar cibiyar sadarwa na gani), ONT (tashar tashar sadarwa ta gani) da ODN (cibiyar rarrabawar gani), Yana a matakin hanyar sadarwar hanyar sadarwa kuma galibi ya dace da samun damar fiber na gani don ayyukan watsa labarai.
Kayan aikin cibiyar sadarwa mai aiki sun haɗa da kayan tara kayan ofis na tsakiya (OLT) da naúrar cibiyar sadarwa ta gani (ONU).Naúrar hanyar sadarwa ta gani (ONU) tana ba masu amfani da mu'amala tsakanin bayanai, bidiyo, da cibiyoyin sadarwar tarho da PON.Matsayin farko naONUshine karɓar siginar gani sannan a canza shi zuwa tsarin da mai amfani ke buƙata (Ethernet, watsawar IP, tarho, T1/E1, da sauransu).An haɗa kayan aikin OLT zuwa cibiyar sadarwar IP ta hanyar fiber na gani.Gabatar da hanyar sadarwa ta hanyar sadarwa tana da yanki mai ɗaukar hoto har zuwa 20km, wanda ke ba da tabbacin cewa za a iya haɓaka OLT zuwa kuɗaɗɗen haɗin gwiwar birni na gargajiya daga matakin farko na ginin hanyar sadarwa na gani, don haka sauƙaƙe tsarin hanyar sadarwa na hanyar sadarwa. convergence Layer da ajiye adadin karshen ofisoshin.Bugu da kari, halayen babbar hanyar sadarwa ta hanyar sadarwa ta gani, babban damar isa ga bandwidth, babban dogaro, da damar tallafin matakin QoS masu yawan ayyuka sun kuma sanya juyin halittar hanyar sadarwa zuwa ga hadadden dandamali, hadewa, da ingantaccen dandamali mai dauke da gaskiya.
2.Basic Principles of EPON Network
Tsarin EPON yana amfani da fasahar WDM don cimma nasarar watsa nau'i-nau'i na fiber guda ɗaya, ta yin amfani da 1310nm na sama da ƙananan raƙuman ruwa na 1490nm don watsa bayanai da murya, kuma sabis na CATV suna amfani da 1550nm wavelength don ɗauka. An sanya OLT a ofishin tsakiya don rarrabawa da sarrafa tashar tashar. haɗi, kuma yana da kulawa na ainihi, gudanarwa da ayyukan kulawa.Ana sanya ONU a gefen mai amfani, kuma OLT da ONU ana haɗa su a cikin hanyar 1:16/1:32 ta hanyar hanyar sadarwa mai rarraba kayan gani.
Domin raba sigina daga masu amfani da yawa akan fiber iri ɗaya, ana iya amfani da waɗannan dabaru iri-iri biyu masu zuwa.
1) Rafin bayanan da ke ƙasa yana ɗaukar fasahar watsa shirye-shirye.
A cikin EPON, ana aika tsarin watsa bayanan ƙasa daga OLT zuwa ONU masu yawa ta hanyar watsa bayanai.Ana watsa bayanai a ƙasa daga OLT zuwa ONU masu yawa a cikin nau'in fakiti masu tsayi masu tsayi. Kowane fakitin bayanai yana daEPONfakitin kai, wanda ke tantance ko an aika fakitin bayanin zuwa ONU-1, ONU-2 ko ONU-3.Hakanan ana iya gano shi azaman fakitin watsa shirye-shirye da aka aika zuwa duk ONUs ko zuwa takamaiman rukunin ONU (fakitin multicast).Lokacin da bayanan suka isa ONU, ONU tana karɓar kuma ta gano fakitin bayanan da aka aika zuwa gare ta ta hanyar daidaita adireshin, kuma ta watsar da fakitin bayanan da aka aika zuwa wasu ONUs.An ware LLID na musamman bayan an yi rajistar ONU;OLT yana kwatanta lissafin rajistar LLID lokacin karɓar bayanai, kuma lokacin da ONU ya karɓi bayanai, kawai yana karɓar firam ko firam ɗin watsa shirye-shiryen da suka dace da nasa LLID.
2) kwararar bayanai na sama suna ɗaukar fasahar TDMA.
OLT yana kwatanta lissafin rajista na LLID kafin karɓar bayanai;kowane ONU yana aika da firam ɗin bayanai a cikin ramin lokaci daidai da abin da babban ofishin kayan aikin OLT ya keɓe;Ramin lokacin da aka keɓance (ta hanyar fasahar kewayon) yana rama tazarar tazara tsakanin kowane ONU kuma yana guje wa kowane ONU karo tsakanin.