Iyo EPON system ine akawanda optical network units (ONU), chinomira mutsetse wemagetsi (OLT), uye imwe kana akawanda optical network (ona Mufananidzo 1). Munzira yekuwedzera, chiratidzo chinotumirwa neOLTinotepfenyurwa kune veseONUs. 8h Shandura fomati yefomati, tsanangurazve chikamu chepamberi, uye wedzera iyo nguva uye zvine musoro chiziviso (LLID)). Iyo LLID inozivisa imwe neimweONUmuPON system, uye iyo LLID inotsanangurwa panguva yekutsvaga maitiro.
(1) Kukura
MuEPON system, chinhambwe chemuviri pakati pechimwe nechimweONUuyeOLTmurwizi rwekukwidza ruzivo nzira haina kuenzana. Iyo general EPON system inotaura kuti chinhambwe chakareba pakatiONUuyeOLTiri 20km, uye chinhambwe chipfupi i0km. Uyu mutsauko wechinhambwe uchakonzera kunonoka kusiyanisa pakati pe0 ne200 isu. Kana pasina gaka rakakwana rekuzviparadzanisa nevamwe, zviratidzo kubva kwakasiyanaONUsinogona kusvika pakuguma kwekugamuchira kweOLTpanguva imwe chete, izvo zvinozokonzera kupesana kwezviratidzo zvekumusoro. Iko kukakavara kunokonzeresa kuwanda kwekukanganisa uye kurasikirwa kwekuyananisa, nezvimwe, zvichikonzera kuti sisitimu itadze kushanda zvakajairika. Uchishandisa nzira yekuenzanisa, tanga wayera chinhambwe chemuviri, wozogadzirisa zveseONUskusvika kune imwechete inonzwisisika chinhambwe seOLT, wobva waita nzira yeTDMA kuti uwane kudzivirira kunetsana. Parizvino, nzira dzakasiyana-siyana dzinoshandiswa dzinosanganisira kupararira-kutenderera, kunze-kwe-bhendi kubva uye mu-bhendi-kuvhura hwindo. Semuyenzaniso, iyo time tag kubva nzira inoshandiswa kutanga kuyera chiratidzo chekunonoka nguva kubva kune yega yegaONUkuOLT, uye wobva waisa chaiyo yakaenzana kunonoka Td kukosha kune yega yegaONU, kuitira kuti loop inonoke nguva yezvoseONUsmushure mekuisa Td ( Inonzi kuenzana loop kunonoka kukosha Tequ) yakaenzana, mhedzisiro yakafanana neiyo yegaONUinofambiswa kune chinhambwe chine musoro seOLT, uye ipapo furemu inogona kutumirwa nemazvo zvinoenderana neiyo TDMA tekinoroji pasina kupokana. .
(2) Kuwana nzira
TheOLTanoona kutiONUmuPON system inotumira Gate MPCP mameseji nguva nenguva. Pakugamuchira Gate message, vasina kunyoreswaONUichamirira nguva yakasarudzika (kudzivisa kunyoreswa panguva imwe chete kweakawandaONUs), uye wozotumira Register meseji kuOLT. Mushure mekubudirira kunyoresa, iyoOLTinopa LLID kune iyoONU.
(3) Ethernet OAM
Mushure meONUakanyoresa neOLT, iyo Ethernet OAM paneONUinotanga maitiro ekutsvaga uye inotanga kubatana neOLT. Ethernet OAM inoshandiswa paONU/OLTzvinongedzo kuti uwane zvikanganiso zviri kure, konzeresa kure loopbacks, uye kuona yekubatanidza mhando. Nekudaro, Ethernet OAM inopa rutsigiro rweakagadziridzwa OAM PDUs, ruzivo mayuniti uye nguva mishumo. VazhinjiONU/OLTvagadziri vanoshandisa OAM ekuwedzera kuseta akakosha mabasa eONUs. Chishandiso chakajairika ndechekudzora bandwidth yevashandisi vekupedzisira neiyo yekumisikidza bandwidth modhi yakawedzerwa muONU. Iyi isiri-standard application ndiyo kiyi yekuyedzwa uye inova chipingamupinyi kune intercommunication pakatiONUuyeOLT.
(4) Kuyerera kwemvura yakadzika
Apo iyoOLTine traffic kutumira iyoONU, ichatakura ruzivo rweLLID rwekwauri kuendaONUmumigwagwa. Nekuda kwekutepfenyura maitiro ePON, data rakatumirwa neOLTichatepfenyurwa kune veseONUs. Isu tinofanirwa kunyanya kufunga nezvemamiriro ezvinhu apo traffic yakadzika inofambisa vhidhiyo sevhisi hova. Nekuda kwekutepfenyura kweiyo EPON sisitimu, kana mushandisi akagadzirisa chirongwa chevhidhiyo, chinozotepfenyurwa kune vese vashandisi, iyo inodya yakadzika bandwidth zvakanyanya.OLTkazhinji inotsigira IGMP Snooping. Inogona snoop IGMP Join Chikumbiro meseji uye kutumira multicast data kune vashandisi vane hukama neboka iri pane kutepfenyura kune vese vashandisi, kuderedza traffic neiyi nzira.
(5) Kuyerera kwemvura
Mumwe cheteONUinogona kutumira traffic pane imwe nguva. TheONUine mitsetse yakawanda yakakosha (mutsetse wega wega unoenderana neQoS levelONUinotumira Report meseji kuneOLTkukumbira mukana wekutumira, kutsanangura mamiriro emutsetse wega wega. TheOLTinotumira Gate meseji ichipinduraONU, vachiudzaONUnguva yekutanga yekufambisa kunotevera TheOLTinofanirwa kukwanisa kubata bandwidth zvinodiwa kune veseONUs, uye inofanira kukoshesa mvumo yekufambisa. Zvinoenderana nekukosha kwemutsetse uye kuenzanisa zvikumbiro zveakawandaONUs, ivoOLTinofanirwa kukwanisa kubata bandwidth zvinodiwa kune veseONUs. Dynamic kugovera kwekumusoro bandwidth (kureva DBA algorithm).
2.2 Zvinoenderana nehunyanzvi hunhu hweEPON system, matambudziko ebvunzo akatarisana neEPON system
(1) Tichifunga nezve chiyero cheEPON system
Nyangwe IEEE802.3ah isingatsananguri huwandu hwehuwandu hwehuwandu muhurongwa hweEPON, nhamba yepamusoro inotsigirwa neEPON system inobva pa16 kusvika pa128. Imwe neimweONUkujoinha chirongwa cheEPON kunoda musangano weMPCP neOAM. Sezvo mamwe masaiti ajoinha EPON, njodzi yekukanganisa kwehurongwa ichawedzera. Somuenzaniso, mumwe nomumweONUinoda kutsvagazve maitiro, maitiro ekupinda uye kutanga OAM chikamu. Nokudaro, nguva yekudzorera yehurongwa hwose ichawedzera nehuwandu hweONUs.
(2) Dambudziko rekupindirana kwemidziyo
Izvi zvinotevera zvinhu zvinonyanya kutariswa kune intercommunication yemidziyo:
● The dynamic bandwidth algorithm (DBA) inopiwa nevagadziri vakasiyana yakasiyana.
●Vamwe vagadziri vanoshandisa “Organization Specific Elements” yeOAM kutara maitiro chaiwo.
●Kuti kugadzirwa kweMPCP protocol kunoenderana here.
●Kuti nzira dzekuyera kureba dzakagadzirwa nevagadziri vakasiyana dzinoenderana nekugadzirisa wachi.
(3) Njodzi dzakavanzwa mukufambiswa kwemasevhisi ekutamba katatu muEPON system
Nekuda kwehunhu hwekutapurirana hweEPON, dzimwe njodzi dzakavanzika dzinozounzwa kana uchitumira katatu masevhisi ekutamba:
● Kudzika kwemvura kunoparadza zvakawanda zvebhanwidth: EPON system inoshandisa nhepfenyuro yekufambisa nzira muzasi: imwe neimweONUichagamuchira huwandu hukuru hwetraffic inotumirwa kune vamweONUs, kutambisa yakawanda yekudzika bandwidth.
●Kunonoka kwekumusoro kwerwizi kwakakura: Kana iyoONUinotumira data kuneOLT, inofanirwa kumirira mukana wekutapurirana wakapihwa neOLT. Naizvozvo, theONUinofanirwa kuvharira huwandu hukuru hwetraffic yekumusoro, izvo zvinokonzeresa kunonoka, jitter, uye kurasikirwa kwepaketi.
3 EPON bvunzo tekinoroji
Muedzo weEPON unonyanya kusanganisira zvinhu zvakati wandei senge interoperability test, protocol test, system transmission performance test, sevhisi uye basa rekuona. Iyo yakajairwa test topology inoratidzwa muMufananidzo 2. Zvigadzirwa zveIXIA zveIxN2X zvinopa kadhi rekuedza reEPON rakatsaurirwa, EPON test interface, inogona kutora nekuongorora maprotocol eMPCP neOAM, inogona kutumira EPON traffic, inopa chirongwa chekuyedza otomatiki, uye inogona kubatsira vashandisi kuyedza. DBA algorithms.
