Uthungelwano lwe-EPON lusebenzisa indlela ye-FTTB ukwenza uthungelwano, kunye neeyunithi zayo zenethiwekhi ezisisisekoOLTkunye ne-ONU.I-OLT ibonelela ngamazibuko e-PON amaninzi kwizixhobo ze-ofisi ephakathi ukuqhagamshela kwizixhobo ze-ONU;I-ONU sisixhobo somsebenzisi ukubonelela ngedatha ehambelanayo kunye nojongano lwelizwi ukuqonda ukufikelela kwenkonzo yomsebenzisi.Ukuqonda ukufikelela kwiinkonzo ezahlukeneyo ikakhulu kukusebenzisa iithegi ezahlukeneyo zeVLAN abasebenzisi abahlukeneyo kunye neenkonzo ezahlukeneyo ukuhambisa ngokuphandle kwiseva yokufikelela kwinkonzo ehambelanayo, kwaye uthumele iithegi zeVLAN ezihambelanayo kuthungelwano lomthwali we-IP ukuhanjiswa.

1.Intshayelelo kwi-EPON Network

I-EPON (i-Ethernet Passive Optical Network) yiteknoloji ye-fiber ephumayo yokufikelela kwi-fiber network, eyamkela i-point-to-multipoint structure, i-passive optical fiber transmission mode, esekelwe kwi-platform ye-Ethernet ye-high-speed kunye ne-TDM ixesha lokwahlula i-MAC (MediaAccessControl) indlela yokulawula ukufikelela kwimidiya. , Ukubonelela ngeteknoloji yokufikelela kwi-broadband kwiinkonzo ezahlukeneyo ezidibeneyo.Okubizwa ngokuthi "i-passive" ithetha ukuba i-ODN ayinayo nayiphi na i-electronic device esebenzayo kunye nezixhobo zombane, kwaye iqulethwe ngokupheleleyo izixhobo ezingabonakaliyo ezifana ne-optical splitters (Splitter).Isebenzisa itekhnoloji ye-PON kumaleko womzimba, iprotocol ye-Ethernet kumaleko wekhonkco, kwaye isebenzisa i-PON topology ukufikelela kwi-Ethernet.Ngoko ke, idibanisa iingenelo zeteknoloji ye-PON kunye nobuchwepheshe be-Ethernet: ixabiso eliphantsi, i-bandwidth ephakamileyo, i-scalability enamandla, ukulungelelaniswa okuguquguqukayo kunye nokukhawuleza kwenkonzo, ukuhambelana ne-Ethernet ekhoyo, ulawulo olufanelekileyo, njalo njalo.

I-EPON inokuqonda ukudityaniswa kwelizwi, idatha, ividiyo, kunye neenkonzo zeselfowuni.Inkqubo ye-EPON iqulunqwe ikakhuluOLT(i-terminal ye-optical line), i-ONU (iyunithi yenethiwekhi ye-optical), i-ONT (i-terminal network ye-optical network) kunye ne-ODN (inethiwekhi yokusabalalisa i-optical), Ikwinqanaba lenethiwekhi yokufikelela kwinethiwekhi kwaye ifaneleka kakhulu ukufikelela kwi-fiber optical kwiinkonzo ze-broadband.

Izixhobo zenethiwekhi ezisebenzayo ziquka izixhobo zokubeka i-ofisi ephakathi (OLT) kunye neyunithi yenethiwekhi ye-optical (ONU).Iyunithi yenethiwekhi ye-optical network (ONU) ibonelela abasebenzisi nge-interface phakathi kwedatha, ividiyo, kunye neenethiwekhi zefowuni kunye nePON.Indima yokuqala yeI-ONUkukufumana umqondiso we-optical kwaye emva koko uyiguqule kwifomathi efunwa ngumsebenzisi (i-Ethernet, ukusasazwa kwe-IP, umnxeba, i-T1 / E1, njl.).Izixhobo ze-OLT ziqhagamshelwe kwinethiwekhi engundoqo ye-IP ngefiber optical.Ukwaziswa kothungelwano lwe-optical access inendawo yokufikelela ukuya kuthi ga kwi-20km, eqinisekisa ukuba iOLT inokuphuculwa ukuya kwindawo yesiqhelo ye-metropolitan convergence node ukusuka kwinqanaba lokuqala lolwakhiwo lwe-optical access network, ngaloo ndlela yenza lula ubume bothungelwano lokufikelela kuthungelwano. convergence layer kunye nokugcina inani leeofisi zokuphela.Ukongeza, iimpawu zenethiwekhi yokufikelela kumandla amakhulu, i-bandwidth ephezulu yokufikelela, ukuthembeka okuphezulu, kunye neenkonzo ezininzi ze-QoS zenkxaso yezakhono ziye zenza ukuvela kothungelwano lokufikelela kwiqonga elidibeneyo, elidibeneyo, nelisebenzayo.

2.Imigaqo esisiseko ye-EPON Network

Inkqubo ye-EPON isebenzisa iteknoloji ye-WDM ukufezekisa i-fiber-fiber bidirectional transmission, isebenzisa i-1310nm ephezulu kunye ne-1490nm ye-wavelengths esezantsi yokuhambisa idatha kunye nezwi, kunye neenkonzo ze-CATV zisebenzisa i-1550nm ubude be-wavelength. uqhagamshelo, kwaye inokubekwa kweliso kwexesha lokwenyani, ulawulo nokugcinwa kwemisebenzi.I-ONU ibekwe kwicala lomsebenzisi, kwaye i-OLT kunye ne-ONU zidityaniswe ngendlela ye-1:16/1:32 ngokusebenzisa inethiwekhi yokusabalalisa i-passive optical.

Ukuze ukwahlula imiqondiso kubasebenzisi abaninzi kwifayibha enye, ezi ndlela zimbini zilandelayo zokuphindaphinda zinokusetyenziswa.

1) Umjelo wedatha osezantsi wamkela iteknoloji yosasazo.

Kwi-EPON, inkqubo yokuhanjiswa kwedatha esezantsi ukusuka kwi-OLT ukuya kwii-ONU ezininzi ithunyelwa ngokusasazwa kwedatha.Idatha isasazwa ezantsi ukusuka kwiOLT ukuya kwii-ONU ezininzi ngohlobo lweepakethi zobude obuguquguqukayo.Ipakethi nganye yolwazi ineEPONiheader yepakethe, echonga ngokukodwa ukuba ipakethi yolwazi ithunyelwe kwi ONU-1, ONU-2 okanye ONU-3.Isenokuchongwa njengepakethi yosasazo ethunyelwe kuzo zonke ii-ONU okanye kwiqela elithile le-ONU (iipakethi ezininzi).Xa idatha ifika kwi-ONU, i-ONU ifumana kwaye ichonge iipakethe zolwazi ezithunyelwe kuyo ngokudibana kwedilesi, kwaye ilahle iipakethi zolwazi ezithunyelwe kwezinye ii-ONU.I-LLID eyodwa yabelwa emva kokuba i-ONU ibhalisiwe;i-OLT ithelekisa uluhlu lobhaliso lwe-LLID xa ifumana idatha, kwaye xa i-ONU ifumana idatha, ifumana kuphela izakhelo okanye izakhelo zokusasaza ezihambelana ne-LLID yayo.

I-2) Ukuhamba kwedatha ephezulu kwamkela iteknoloji ye-TDMA.

I-OLT ithelekisa uluhlu lobhaliso lwe-LLID ngaphambi kokufumana idatha;i-ONU nganye ithumela isakhelo sedatha kwixesha elibekiweyo ngokulinganayo elabelwe izixhobo zeofisi ephakathi OLT;ixesha elabelwe ixesha elibekiweyo (ngokusebenzisa itekhnoloji eqalayo) ihlawulela umgama womgama phakathi kwe-ONU nganye kwaye inqanda ukungqubana kwe-ONU nganye phakathi.