Netiweki ya EPON imagwiritsa ntchito njira ya FTTB kupanga netiweki, ndipo mayunitsi ake oyambira aliOLTndi ONU.OLT imapereka madoko ochulukirapo a PON kuti zida zapakati zaofesi zilumikizane ndi zida za ONU; ONU ndi zida zogwiritsa ntchito kuti zipereke data yofananira ndi maulalo amawu kuti muzindikire mwayi wogwiritsa ntchito ntchito zosiyanasiyana. ogwiritsa ntchito osiyanasiyana ndi mautumiki osiyanasiyana kuti atumize momveka ku seva yolumikizirana, ndikutumiza ma tag ofananira a VLAN ku netiweki ya IP kuti atumizidwe.

1.Chiyambi cha EPON Network

EPON (Ethernet Passive Optical Network) ndiukadaulo waukadaulo waukadaulo wa fiber access network, womwe umagwiritsa ntchito mawonekedwe a point-to-multipoint, passive optical fiber transmission mode, kutengera nsanja ya Ethernet yothamanga kwambiri komanso gawo la TDM nthawi ya MAC (MediaAccessControl) njira yowongolera media. , Perekani teknoloji yofikira ma broadband kwa mautumiki osiyanasiyana ophatikizika.Zomwe zimatchedwa "passive" zikutanthauza kuti ODN ilibe zipangizo zamagetsi zogwira ntchito ndi mphamvu zamagetsi, ndipo zimapangidwa ndi zipangizo zopanda kanthu monga optical splitters (Splitter).Imagwiritsa ntchito ukadaulo wa PON pazosanjikiza zakuthupi, protocol ya Efaneti pa ulalo wosanjikiza, ndipo imagwiritsa ntchito PON topology kuti ikwaniritse Efaneti.Chifukwa chake, imaphatikiza zabwino zaukadaulo wa PON ndi ukadaulo wa Efaneti: mtengo wotsika, bandwidth yayikulu, scalability yamphamvu, kusinthika komanso kukonzanso kwautumiki, kuyanjana ndi Ethernet yomwe ilipo, kasamalidwe kosavuta, ndi zina zotero.

EPON imatha kuzindikira kuphatikiza kwa mawu, data, makanema, ndi ntchito zamafoni.Dongosolo la EPON limapangidwa makamaka ndiOLT(Optical line terminal), ONU (optical network unit), ONT (optical network terminal) ndi ODN (optical distribution network), Ili pamlingo wofikira netiweki ya netiweki ndipo ndiyofunika kwambiri pakugwiritsa ntchito ma fiber opangira mautumikiwa.

Zida zamagetsi zogwira ntchito zimaphatikizapo zida zapakati paofesi (OLT) ndi optical network unit (ONU).Optical network unit (ONU) imapatsa ogwiritsa ntchito mawonekedwe pakati pa data, makanema, ndi maukonde amafoni ndi PON.Udindo woyamba waONUndikulandira chizindikiro cha kuwala ndikuchisintha kukhala mtundu wofunidwa ndi wogwiritsa ntchito (Efaneti, IP kuwulutsa, foni, T1/E1, etc.).Zida za OLT zimalumikizidwa ndi netiweki ya IP core kudzera mu fiber optical.Kumayambiriro kwa netiweki ya kuwala kofikira kumakhala ndi malo ofikira mpaka 20km, zomwe zimawonetsetsa kuti OLT ikhoza kusinthidwa kukhala njira yolumikizirana yamtundu wamtundu kuyambira pagawo loyambira la zomangamanga zolumikizira maukonde, motero kufewetsa mawonekedwe a maukonde a netiweki. convergence layer ndikusunga kuchuluka kwa maofesi omaliza.Kuphatikiza apo, mawonekedwe a kuchuluka kwa netiweki yofikira, kuchuluka kwa bandwidth, kudalirika kwakukulu, komanso kuthekera kothandizira kwamagawo angapo a QoS apangitsanso kusinthika kwa netiweki kupita ku nsanja yolumikizana, yophatikizika, komanso yogwira bwino ntchito.

2.Mfundo Zazikulu za EPON Network

Dongosolo la EPON limagwiritsa ntchito teknoloji ya WDM kuti ikwaniritse maulendo amtundu umodzi wa fiber bidirectional transmission, pogwiritsa ntchito 1310nm kumtunda ndi kumtunda kwa 1490nm wavelengths kuti atumize deta ndi mawu, ndipo ntchito za CATV zimagwiritsa ntchito 1550nm wavelength kunyamula. kugwirizana, ndipo ili ndi ntchito zowunikira nthawi yeniyeni, kasamalidwe ndi kukonza.ONU imayikidwa kumbali ya wogwiritsa ntchito, ndipo OLT ndi ONU zimagwirizanitsidwa mu 1:16 / 1:32 njira kudzera mu network yogawa yogawa.

Pofuna kulekanitsa zizindikiro kuchokera kwa ogwiritsa ntchito angapo pamtundu womwewo, njira ziwiri zotsatirazi zochulukitsa zingagwiritsidwe ntchito.

1) Kutsikira kwa data kumatengera ukadaulo wowulutsa.

Mu EPON, njira yotumizira deta yotsika kuchokera ku OLT kupita ku ma ONU angapo imatumizidwa ndi kuwulutsa kwa data.Deta imawulutsidwa pansi kuchokera ku OLT kupita ku ma ONU angapo monga mapaketi akutali-kutalika.EPONmutu wa paketi, womwe umazindikiritsa mwapadera ngati paketi yazidziwitso imatumizidwa ku ONU-1, ONU-2 kapena ONU-3.Itha kudziwikanso ngati paketi yowulutsa yomwe imatumizidwa ku ma ONU onse kapena ku gulu linalake la ONU (paketi ya multicast).Deta ikafika ku ONU, ONU imalandira ndikuzindikiritsa mapaketi azidziwitso omwe amatumizidwa kwa iyo kudzera pakufananiza ma adilesi, ndikutaya mapaketi azidziwitso omwe amatumizidwa ku ma ONU ena.LLID yapadera imaperekedwa pambuyo polembetsa ONU;OLT imafanizira mndandanda wa zolembera za LLID polandira deta, ndipo ONU ikalandira deta, imangolandira mafelemu kapena mafelemu owulutsa omwe amafanana ndi LLID yake.

2) Kuthamanga kwa data kumtunda kumatengera luso la TDMA.

OLT ikufanizira mndandanda wolembetsa wa LLID musanalandire deta;aliyense ONU amatumiza chimango deta mu nthawi kagawo uniformly kuperekedwa ndi chapakati ofesi zida OLT;nthawi yomwe yaperekedwa (kudzera muukadaulo wosiyanasiyana) imalipira kusiyana kwa mtunda pakati pa ONU iliyonse ndikupewa Kugundana kulikonse kwa ONU pakati.