Ngokuthuthukiswa okuqhubekayo kokwakhiwa kwenethiwekhi yesivinini esikhulu kanye nesidingo sokwakha impilo ehlakaniphile yedijithali ngokusekelwe kumakhono enethiwekhi "ama-gigabit amathathu", opharetha badinga amabanga amade okudlulisela, ama-bandwidth aphezulu, ukwethembeka okunamandla kanye nezindleko eziphansi zokusebenza kwebhizinisi (OPEX), kanye I-GPON isekela imisebenzi eminingi ukuze ihlangabezane nezidingo zamakhasimende.
Iyini i-GPON?
I-GPON isifinyezo se-Gigabit Passive Optical Network, esichazwa uchungechunge lwezincomo ze-ITU-T G.984.1 kuya ku-G.984.6.I-GPON ayikwazi ukudlulisa hhayi i-Ethernet kuphela, kodwa futhi i-ATM ne-TDM (PSTN, ISDN, E1 ne-E3) ithrafikhi.Isici sawo esiyinhloko ukusetshenziswa kwezihlukanisi ezingenzi lutho kunethiwekhi yokusabalalisa i-fiber optical, enomshini wokufinyelela we-point-to-multipoint, ukusebenzisa i-fiber optical eyodwa engenayo kusukela endaweni emaphakathi yomhlinzeki wenethiwekhi ukuze kusetshenziswe imizi eminingi kanye nabasebenzisi bamabhizinisi amancane.
I-GPON, i-EPON ne-BPON
I-EPON (i-Ethernet Passive Optical Network) kanye ne-GPON anezincazelo ezifanayo kakhulu.Womabili amanethiwekhi e-PON futhi womabili asebenzisa izintambo zokubona kanye nemvamisa yokubona efanayo.Izinga lala manethiwekhi amabili endaweni ekhuphuka nomfula cishe li-1.25 Gbits/s.Futhi i-BPON (Broadband Passive Optical Network) ne-GPON nazo zifana kakhulu.Zombili zisebenzisa ama-optical fibers futhi zingahlinzeka ngezinsizakalo kubasebenzisi abangu-16 kuya kwabangu-32.Ukucaciswa kwe-BPON kulandela i-ITU-T G983.1, kanti i-GPON ilandela i-ITU-T G984.1.Lapho izicelo ze-PON ziqala ukwethulwa, i-BPON yayidume kakhulu.
I-GPON idume kakhulu emakethe ye-fiber optical.Ngaphezu kobuchwepheshe bayo obuthuthukisiwe, futhi inezinzuzo ezilandelayo:
1.Ububanzi: Ifayibha yemodi eyodwa ingadlulisa idatha ukusuka kumakhilomitha ayi-10 kuye kwangama-20, kuyilapho izintambo zethusi ezivamile ngokuvamile zilinganiselwe ebangeni lamamitha ayi-100.
2.Isivinini: Izinga lokudlulisa umfula ongezansi le-EPON liyafana nezinga layo elikhuphuka nomfula, elingu-1.25 Gbit/s, kuyilapho izinga lokudlulisela eliya phansi komfula le-GPON lingu-2.48 Gbit/s.
I-3.Ukuphepha: Ngenxa yokuhlukaniswa kwezibonakaliso ku-fiber optical, i-GPON iwuhlelo oluphephile.Ngenxa yokuthi zidluliselwa kumjikelezo ovaliwe futhi ziqukethe ukubethela, i-GPON ayikwazi ukugetshengwa noma ukuthepha.
4.Ukukwazi ukuthengeka: Izintambo ze-GPON fibre optic ishibhile kunezintambo ze-LAN zethusi, futhi zingagwema nokutshalwa kwezimali kuzintambo kanye nemishini kagesi ehlobene, ngaleyo ndlela yonga izindleko.
I-5.Ukonga amandla: Ngokuphambene nentambo yethusi evamile kumanethiwekhi amaningi, ukusebenza kahle kwamandla kwe-GPON kukhuphuke ngo-95%.Ngaphezu kokusebenza kahle, i-gigabit passive optical networks iphinde inikeze isisombululo esingabizi kakhulu esingandisa abasebenzisi ngokusebenzisa ama-splitters, adume kakhulu ezindaweni ezinabantu abaningi.