Ngokuthuthukiswa kwamadolobha esimanje maqondana nemisebenzi eminingi, ukwakheka kwedolobha kuya ngokuya kuba nzima, futhi kukhona amakhulu, amakhulu, noma izinkulungwane zamaphoyinti okuqapha aphansi. Ukuqinisekisa ukuthi iminyango esebenzayo iyakwazi ukubamba izithombe zevidiyo zesikhathi sangempela, ezicacile nezisezingeni eliphezulu ngokushesha okukhulu, Gqamisa ukungezwani kwezinsiza ze-fiber optic. Ngaphezu kwalokho, emisebenzini yanamuhla yasemadolobheni ekhula ngamandla futhi eyinkimbinkimbi, ukuphinda kubekwe izintambo ze-fiber-optic akubizi nje kuphela, kodwa ukuxhumana phakathi kwazo zonke izinhlangothi kunzima nakakhulu. Ngokubheka lokhu, indlela yokuxazulula izinkinga ezingenhla?
Eqinisweni, inkinga efanayo kwahlangatshezwana nayo ekwakhiweni kwe-FTTH (Fiber to the Home) ngabaqhubi bezokuxhumana. Ukuze uxazulule le nkinga, nikeza ukudlala okugcwele kuzinzuzo zomkhawulokudonsa we-fiber optical, ukuxazulula ukushoda kwezinsiza ze-fiber optical, futhi uthuthukise ukuthembeka kwenethiwekhi, opharetha bezokuxhumana bakhethe ubuchwepheshe be-PON (i-passive optical network). Lobu buchwepheshe bungasetshenziswa ekuqaphelweni kwenethiwekhi yokuphepha.
I-PON (PassiveOpticalNetwork) iyinethiwekhi yokubona engenzi lutho. Inethiwekhi ye-passive optical ihlanganisa itheminali yomugqa obonakalayo (OLT) efakwe esiteshini sokulawula esimaphakathi, kanye nesethi yamayunithi enethiwekhi optical (ONU) afanayo afakwe ezakhiweni zomsebenzisi. Inethiwekhi yokusabalalisa ebonakalayo (ODN) phakathi kwe-OLTfuthi i-ONU iqukethe imicu yokubona kanye nezihlukanisi ze-passive optical noma ama-couplers.
Inethiwekhi yokubona yokwenziwa ayinawo amadivaysi asebenzayo ukusuka phakathi nendawo kuya kunethiwekhi yendawo. Esikhundleni salokho, amadivaysi e-optical optical afakwa kunethiwekhi futhi ithrafikhi edlulisiwe iqondiswa ngokuhlukanisa amandla we-wavelength optical kuyo yonke indlela. Lokhu kushintsha kuqeda isidingo sokuthi abasebenzisi banikeze futhi bagcine amadivaysi asebenzayo ku-loop yokudlulisela, okusindisa kakhulu izindleko zomsebenzisi. Izihlukanisi ze-Passive optical kanye nama-couplers adlala indima kuphela yokudlulisa nokukhawulela ukukhanya, akudingi ukuhlinzekwa kwamandla kagesi nokucutshungulwa kolwazi, futhi anesikhathi esimaphakathi esingakhawulelwe phakathi kokuhluleka, okunganciphisa izindleko zokunakekela ngendlela eyindilinga.
Izinzuzo zobuchwepheshe be-PON zibonakala ikakhulukazi kulezi zici ezilandelayo:
1. Inethiwekhi yokufinyelela i-Optical fiber iyisixazululo esifaneleka kakhulu sokuthuthukiswa kwesikhathi esizayo, ikakhulukazi ubuchwepheshe be-PON buye bafakazelwa ukuthi buyindlela engabizi kakhulu ekufinyeleleni kwamanje okuhlanganisiwe kwe-broadband.
2. Ngenxa yokusetshenziswa kobuchwepheshe be-PON, yonke inethiwekhi yokusabalalisa i-optical ayisebenzi, futhi inethiwekhi ye-passive optical incane ngosayizi futhi ilula emishinini. Uma kuqhathaniswa namanethiwekhi ezintambo zethusi, i-PON inganciphisa izindleko zokulungisa nokusebenza, futhi igweme ngokuphelele ukuphazamiseka kazibuthe nokuphazanyiswa kombani.
3. Isenzo sokwenziwaI-ONU(iyunithi yenethiwekhi ye-optical) ye-PON ayidingi ukunikezwa kwamandla kagesi, okungagcini nje ngokuqeda uchungechunge lwezinkinga zokunikezwa kwamandla, kodwa futhi kunokwethenjelwa okungcono kunemishini esebenzayo.
4. Ngenxa yokuthi izingxenye ze-passive zisetshenziswa futhi i-optical fiber transmission medium yabiwe, izindleko zokutshala izimali zayo yonke inethiwekhi ye-optical ziphansi.
5. I-PON isobala ohlelweni lokudlulisa olusetshenziswa ngezinga elithile, futhi kulula ukuyithuthukisa.
Ubuchwepheshe be-PON sebuyikhethelo lokuqala lemboni le-fiber-to-the-home (FTTH). Ubuchwepheshe be-PON busebenzisa i-point-to-multipoint topology, futhi i-downlink ne-uplink idlulisa idatha nge-TDM ne-TDMA ngokulandelanayo. Ibanga phakathi kwe-OLT ne-I-ONUingaba ngu-20km, izinga lokudlulisela liyi-1Gbps ehambisanayo kabili, futhi isilinganiso esiphezulu sokuhlukanisa ngokuvamile sisekela u-1:32 noma ngaphezulu. Ingahlukaniswa ileveli eyodwa noma izihlukanisi eziningi ku-cascade.
Ukusetshenziswa kobuchwepheshe be-PON kungaxazulula ngempumelelo umkhawulokudonsa wokuqapha inethiwekhi kanye nemikhawulo yebanga. IOLTizinto zokusebenza ohlangothini lwehhovisi zisatshalaliswa egumbini lehhovisi ohlangothini lwehhovisi. Ukuhlukaniswa kwe-Multi-level Optical kusetshenziselwa ukubona ukuthunyelwa okuvumelana nezimo kwamaphoyinti. II-ONU+ ikhamera yenethiwekhi isetshenziswa njengenhlanganisela yokugcina. II-ONUkungaba PoEshintshangomsebenzi we-PON. Egunjini lokuqapha lekhasimende neseva yesitoreji. Ingabhekwa ekamelweni lokuqapha ngesikhathi sangempela, futhi idatha yevidiyo ithunyelwa kuseva yesitoreji ngesikhathi esifanayo, okusiza ukuqoqwa kobufakazi ngemva kweqiniso.
Namuhla, "intuthuko ye-optical kanye nokuhoxiswa kwethusi", ukusetshenziswa okubanzi kobuchwepheshe be-PON kubaluleke kakhulu. I-Fengrunda iqalileOLTfuthiI-ONUimishini, kanye nokusekela izixazululo zokuphepha ze-PON, futhi okokuqala wethula i-PoEshintshangomsebenzi we-PON, owakha igebe leI-ONUngaphandle kwe-PoE emakethe yamanje. Uhlelo lokuqapha ividiyo olukude lisebenzisa ubuchwepheshe be-PON luxazulula izinkinga zamaphuzu okuqapha aminyene futhi ayinkimbinkimbi kanye nezinsiza ze-fiber eziqinile emadolobheni anamuhla. Inezinzuzo ezingenakuqhathaniswa ezicini eziningi ezifana nokucushwa kwenethiwekhi, izinsiza zefiber, ikhwalithi yevidiyo, nokuthembeka. Ukuthuthukiswa kwezinsizakalo zokugada amavidiyo akude kunikeza izixazululo ezingcono kakhulu zenethiwekhi.