Iyini i-GPON?
Ubuchwepheshe be-GPON (Gigabit-Capable PON) yisizukulwane sakamuva se-broadband passive optical integrated access standard based on the ITU-TG.984.x standard. Inezinzuzo eziningi ezifana nomkhawulokudonsa ophezulu, ukusebenza kahle okuphezulu, ukumbozwa okukhulu, nokuxhumana okucebile komsebenzisi. Iningi lama-opharetha likuthatha njengobuchwepheshe obufanele ukubona i-broadband kanye noshintsho oluphelele lwezinsiza zenethiwekhi.
I-GPON yahlongozwa okokuqala yinhlangano ye-FSAN ngoSepthemba 2002. Ngalesi sisekelo, i-ITU-T yaqeda ukwakhiwa kwe-ITU-T G.984.1 kanye ne-G.984.2 ngo-March 2003, futhi yaqeda i-G.984.1 kanye ne-G.984.2 ngoFebhuwari nangoJuni. 2004. 984.3 ukumiswa. Ngakho ekugcineni wakha umndeni ojwayelekile we-GPON.
Isakhiwo esiyisisekelo semishini esekelwe kubuchwepheshe be-GPON sifana ne-PON ekhona. Iphinde yakhiweOLT(itheminali ye-optical line) ehhovisi elimaphakathi kanye ne-ONT/I-ONU(itheminali yenethiwekhi yokubona noma ebizwa ngeyunithi yenethiwekhi ebonakalayo) ohlangothini lomsebenzisi. I-ODN (Optical Distribution Network) yenziwe nge-SM fiber kanye ne-passive splitter (Splitter) kanye nohlelo lokuphatha inethiwekhi.
Kwezinye izindinganiso ze-PON, izinga le-GPON lihlinzeka ngomkhawulokudonsa ophezulu ongakaze ubonwe ngaphambili, ngezinga eliphansi lomfula elifika ku-2.5Gbit/s, futhi izici zalo ezingalingani zingavumelana kangcono nemakethe yesevisi yedatha ye-broadband. Ihlinzeka ngesiqinisekiso sesevisi esigcwele se-QoS, futhi iphatha amaseli e-ATM kanye (noma) namafreyimu e-GEM ngesikhathi esifanayo. Inekhono elihle lokuhlinzeka ngamazinga wesevisi, isiqinisekiso sokusekela i-QoS nokufinyelela kwesevisi okugcwele. Uma uphethe amafreyimu e-GEM, amasevisi e-TDM angenziwa imephu kumafreyimu e-GEM, futhi ozimele abajwayelekile abangu-8kHz (125μs) bangasekela ngokuqondile amasevisi e-TDM. Njengezinga lobuchwepheshe lezinga lokuxhumana ngocingo, i-GPON iphinda icacise indlela yokuvikela futhi iqedele imisebenzi ye-OAM ezingeni lenethiwekhi yokufinyelela.
Ezingeni le-GPON, izinhlobo zezinsizakalo ezidinga ukusekelwa zihlanganisa izinsizakalo zedatha (amasevisi e-Ethernet, afaka amasevisi e-IP kanye nokusakaza kwevidiyo ye-MPEG), amasevisi e-PSTN (i-POTS, amasevisi e-ISDN), imigqa ezinikele (T1, E1, DS3, E3, kanye nezinsiza ze-ATM). ) Nezinsizakalo zevidiyo (ividiyo yedijithali). Izinsiza eziningi ku-GPON zifakwe kumephu kumaseli e-ATM noma amafreyimu e-GEM ukuze adluliselwe, anganikeza iziqinisekiso ezihambisanayo ze-QoS zezinhlobo zesevisi ezihlukahlukene.