GPON ndi chiyani?
Ukadaulo wa GPON (Gigabit-Capable PON) ndi m'badwo waposachedwa kwambiri wa burodibandi passive optical Integrated access standard based on ITU-TG.984.x standard. Zili ndi ubwino wambiri monga bandwidth yapamwamba, kuyendetsa bwino kwambiri, kufalikira kwakukulu, mawonekedwe ogwiritsira ntchito olemera, etc. Ogwiritsa ntchito ambiri amawona ngati luso lamakono lokwaniritsa burodibandi ndi kusintha kophatikizana kwa mautumiki a intaneti.
GPON idaperekedwa koyamba ndi bungwe la FSAN mu September 2002. Malingana ndi izi, ITU-T inamaliza chitukuko cha ITU-T G.984.1 ndi G.984.2 mu March 2003, ndipo inamaliza G. mu February ndi June 2004. Standardization of 984.3 . Chifukwa chake, banja lokhazikika la GPON pomaliza limapangidwa.
Mapangidwe oyambira a chipangizocho pogwiritsa ntchito ukadaulo wa GPON ndi wofanana ndi wa PON yomwe ilipo. Ilinso ndiOLT(optical line terminal) ya ofesi yapakati, ONT/ONUya kumapeto kwa wogwiritsa (optical network terminal kapena optical network unit), ndipo zida ziwiri zoyambirira zimalumikizidwa ndi njira imodzi. Optical fiber (SM fiber) ndi passive splitter (Splitter) amapangidwa ndi ODN (Optical Distribution Network) ndi dongosolo loyang'anira maukonde.
Pamiyezo ina ya PON, muyezo wa GPON umapereka chiwongolero chapamwamba chomwe sichinachitikepo ndi kutsika mpaka 2.5 Gbit/s, ndipo mawonekedwe ake asymmetric ndioyenera kwambiri pamsika wamtundu wa data wa Broadband. ndi/kapena mafelemu a GEM. Ili ndi mulingo wabwino wautumiki, chitsimikizo cha QoS komanso mwayi wopezeka ndiutumiki wathunthu. Mukanyamula mafelemu a GEM, ntchito za TDM zitha kujambulidwa kukhala mafelemu a GEM, ndipo mafelemu a 8 kHz (125 μs) amatha kuthandizira mwachindunji ntchito za TDM. Monga mulingo waukadaulo wonyamula, GPON imatchulanso njira zodzitetezera ndikumaliza ntchito za OAM pamlingo wolumikizira netiweki.
Muyeso wa GPON, mitundu ya mautumiki omwe amafunika kuthandizidwa amafotokozedwa momveka bwino: mautumiki a data (mautumiki a Ethernet, kuphatikizapo IP services ndi ma MPEG kanema mitsinje), ntchito za PSTN (POTS, ISDN services), ndi mizere yodzipereka (T1, E1, DS3, E3, ndi ntchito za ATM). ) ndi ntchito zamakanema (kanema wa digito). Ntchito zingapo mu GPON zimajambulidwa ku ma cell a ATM kapena mafelemu a GEM kuti atumizidwe, kupereka zitsimikizo zofananira za QoS zamitundu yosiyanasiyana yautumiki.