Niaj hnub no, Internet yog ib feem tseem ceeb ntawm peb lub neej niaj hnub. Qhov tseeb, muaj ob txoj hauv kev tseem ceeb uas peb siv Is Taws Nem: ib qho yog los ntawm lub xov tooj ntawm tes cov ntaub ntawv kev pabcuam; lwm yam, feem ntau, yog los ntawm broadband tom tsev lossis ua haujlwm.
Los ntawm kev pom kev tshaj lij, kev siv wireless yog wireless nkag. Los ntawm wired, nws yog wired access.
Obviously, cov kev pabcuam cov ntaub ntawv mobile yuav tsum yog wireless. Broadband nyob rau hauv tsev los yog ua hauj lwm yog wired.
Wired access kuj feem ntau hu ua "taw network access" (taw network: tsau xov tooj network). Broadband nkag thiab IPTV nkag mus yog tag nrho "cable."
Qhov kuv xav qhia hnub no yog kev siv broadband.
Kev txhim kho keeb kwm ntawm kev siv internet broadband
Cia peb pib los ntawm qhov pib.
Koj puas tseem nco qab thaum koj thawj zaug pib online?
Lub sijhawm ntxov tshaj plaws los pib nthwv dej hauv Internet yog nyob hauv tsev kawm qib siab. Muaj ib tug xov tooj nyob rau hauv lub tsev so. Thaum koj xav nkag mus rau Is Taws Nem, ntsaws rau hauv koj lub khoos phis tawj daim npav modem, thiab tom qab ntawd teeb tsa tus lej xov tooj hauv koj lub computer.
Tom qab cov kev teeb tsa tiav lawm, pib hu.
Tom qab ib tug creak ntawm "mob siab", nws qhia tau hais tias hu tau zoo, uas yog mus txuas rau hauv Internet.
Qhov ceev ntawm dial-up Internet yog dab tsi? 56Kbps … Tom qab lub suab nrov ntawm "Lub Plawv Tsis Txaus Siab", nws qhia tau tias kev hu xov tooj tau ua tiav, uas yog, kev sib txuas hauv Is Taws Nem.
Qhov ceev ntawm dial-up Internet yog dab tsi? 56 Kbps…
Yog lawm, koj nyeem qhov ntawd, nws qeeb heev. Thaum pib, peb lub tsev so tag nrho tso siab rau lub xov tooj no los hu xov tooj thiab txuas rau lub tsev kawm ntawv kom xaiv cov chav kawm. Lub sijhawm ntawd, thov koj xav txog koj tus kheej. . .
Ntxiv mus, nrog rau txoj kev qub no, thaum koj hu rau Is Taws Nem, lub xov tooj tsis tuaj yeem txuas tau thiab nyob rau hauv lub xeev "tsis khoom". Tsis tas li ntawd xwb, tus nqi kuj tseem kim heev, thiab kev siv Is Taws Nem yog them rau ib feeb ntawm ib feeb, ib yam li kev hu xov tooj. Qhov ceev twb qeeb lawm. Pom cov nyiaj maj nrawm tuaj yeem tua koj tam sim ntawd.
Tom qab ntawd, tom qab ob peb xyoos, ADSL pib muaj. Ib lub gadget zoo li cov duab hauv qab no tshwm sim, hu ua ADSL miv (Modem), cov kab xov tooj tau ntsaws rau hauv ADSL miv, thiab tom qab ntawd tus miv ADSL txuas nrog lub computer los ntawm lub network cable.
Tom qab siv ADSL, lub network ceev kuj tau txhim kho zoo, los ntawm 512Kbps rau 1Mbps, thiab tom qab ntawd mus rau 2Mbps.
Txawm hais tias tus nqi tseem qis, nws nrawm dua li 56K. Lub hauv paus ntawm kev nkag mus rau cov nplooj ntawv web yog du, thiab QQ sib tham sai dua, thiab txhua tus neeg siv Internet tau txhim kho zoo heev.
Qhov ADSL no, uas yog Asymmetric Digital Subscriber Line, yog hom DSL thev naus laus zis. DSL thev naus laus zis tau tsim nyob rau xyoo 1989 los ntawm Bell Communications Research Institute.
Thaum ADSL thawj zaug tshwm sim, kuv xav paub. Nws kuj yog ib lub xov tooj nyias nyias, tsis yog ib khub ntawm lub network cable. Vim li cas qhov nrawm nrawm tuaj?
Nws muab tawm tias thawj kab xov tooj, uas peb tau siv los hu, tsuas yog coj mus rau qhov tsawg zaus ntawm cov xov tooj tooj liab (qhov qis dua 4KHz) thiab tsis paub txog nws qhov peev xwm tag nrho.
ADSL thev naus laus zis siv ntau zaus division multiplexing los faib cov xov tooj zoo tib yam rau hauv peb txoj kev ywj pheej ntawm xov tooj, uplink thiab downlink, uas tsis tsuas yog zam kev cuam tshuam tab sis kuj nce tus nqi.
Tshwj xeeb, ADSL siv DMT (Discrete Multi-Tone) thev naus laus zis los faib cov xov tooj qub los ntawm 4KHz mus rau 1.1MHz zaus band rau 256 subbands nrog bandwidth ntawm 4.3125KHz. Ntawm lawv, cov zaus band hauv qab 4KHz tseem siv los xa POTS (cov kev pabcuam xovtooj ib txwm siv), cov zaus band ntawm 20KHz txog 138KHz yog siv los xa cov teeb liab uplink, thiab zaus band ntawm 138KHz txog 1.1MHZ yog siv los xa cov teeb liab downlink.
Piv nrog rau cov qauv qub, ADSL tsis tsuas yog ua kom nrawm nrawm, tab sis tus nqi kuj poob qis. Thaum koj mus online, koj tsis tas yuav sib tw nrog lub sijhawm. Dab tsi ntxiv, Internet thiab kev hu xov tooj tsis muaj teeb meem ntxiv lawm, thiab tuaj yeem ua tiav ib txhij.
Tom qab ntawd, raws li ADSL, ADSL2 thiab ADSL2 + tau hloov kho dua tshiab, thiab tus nqi tau nce mus txog 20Mbps.
Ntxiv rau ADSL, xov tooj cua thiab TV broadband (cable kev sib txuas lus), ISDN nplooj siab kab thiab lwm yam kev siv Internet tau tshwm sim nyob ib ncig ntawm peb.
Xov tooj cua thiab TV broadband, kuv ntseeg hais tias cov neeg uas tau siv nws yog impressed. Qhov tseeb, nws yog ib txoj hauv kev los muab kev siv dav dav los ntawm coaxial cable ntawm cable TV (CATV).
ISDN sawv cev rau Integrated Services Digital Network. Tus nqi kuj yog siab heev, thiab lub network ceev tsis ceev.
Txawm li cas los xij, txawm hais tias ADSL tau nce lub network ceev heev, qhov kev sib kis ntawm cov xov tooj tooj liab yog qhov kawg txwv. Yog li, nws yog qhov ceev kom nrhiav tau lwm txoj hauv kev.
Yog li ntawd, cov fibers kho qhov muag tau tshwm sim nyob ib puag ncig peb, thiab "kev sib txuas lus kho qhov muag" tau los.
Optical kev sib txuas lus era
Txhua tus yuav tsum tau hnov txog "lub teeb ua ntej tooj liab rov qab". Lub npe hu ua "kev kho qhov muag ua ntej tooj liab thim rov qab" yog, nyob rau hauv cov ntsiab lus nrov, hloov maj mam hloov ntawm tooj liab xov hlau (xov tooj xov tooj, coaxial cables, twisted khub) nrog optical fibers kom ua tiav qhov kev hloov ntawm nqaim-band tooj liab cable tes hauj lwm rau fiber-optic. broadband networks.
Qhov laj thawj rau qhov no yog ib feem yog vim qhov kev thov kom nrawm nrawm, thiab ib feem yog vim tus nqi.
Nrog rau txoj kev loj hlob ntawm lub sij hawm, tus nqi ntawm cov hlau tooj liab tau nce ntau, thaum lub sij hawm tus nqi ntawm optical fiber cables thiab optical transceiver modules tau poob ib xyoos ib zaug. Raws li tus neeg teb xov tooj, tau kawg kuv nyiam pheej yig thiab siv tau yooj yim!
OK, cia peb saib seb qhov fiber ntau no yog dab tsi.
Ua ntej, cia saib tag nrho cov qauv ntawm tus neeg teb xov tooj kev sib txuas lus network:
Nyob rau sab saum toj yog IP nraub qaum network, uas tsuas yog qhov tseem ceeb ntawm tus neeg teb xov tooj. Lub nraub qaum network txuas nrog rau lwm tus neeg ua haujlwm. Cov pob txha caj qaum ntawm cov neeg ua haujlwm sib txawv tsim cov pob txha hauv Internet.
Ntxiv mus, nws tseem txuas nrog rau lwm cov kev pabcuam, xws li PSTN network (xov tooj network) thiab IPTV network, muab cov neeg siv ntau yam kev pabcuam.
Nyob rau hauv lub teb chaws qaum teb network, nws yog lub xeev qaum teb network. Tsis tas li ntawd hauv qab no yog Metropolitan Area Network. Raws li lub npe qhia, nws yog kev sib txuas lus hauv lub nroog.
Tus txiv neej tau muab faib ua peb txheej: txheej txheej, txheej txheej, thiab txheej nkag.
Cov txheej txheem nkag yog txheej ze tshaj plaws rau peb cov neeg siv khoom. Ib feem ntawm kev nkag mus rau lub network no tseem hu ua kev nkag network. Lub hom phiaj thiab qhov nyuaj ntawm "lub teeb ua ntej tooj liab thim rov qab" nyob rau hauv cov txheej txheem nkag.
Tam sim no, qhov tseem ceeb tshaj plaws ntawm kev siv tshuab fiber ntau yog PON.
PON yog Passive Optical Network, passive optical network.
Passive yog dab tsi?
Qhov "qhov chaw" no hais txog lub zog, lub zog, thiab lub zog.
Yuav kom muab tso ncaj, ib qho khoom siv hluav taws xob tsis muaj "qhov chaw" hu ua passive device. Txhawm rau ua kom yooj yim dua, hauv lub network passive, yam koj muab yog qhov koj muaj, tsis muaj lub zog los ua kom zoom lossis hloov pauv.
Piv nrog active optical network, qhov loj tshaj kom zoo dua ntawm passive optical network yog tias nws txo qhov tsis ua hauj lwm tus nqi. Active Cheebtsam yog feem ntau ua rau cov ntsiab lus tsis ua hauj lwm.
Lub network architecture ntawm PON yog raws li nram no:
PON yog tsim los ntawm cov hauv qab no:
OLT(Optical Line Terminal)
Ntawm qhov tod tes, cov teeb liab nqa ntau yam kev pabcuam raug muab sib sau ua ke ntawm lub chaw haujlwm hauv nruab nrab, thiab xa mus rau lub network nkag mus raws li qee yam teeb liab hom kev xa mus rau cov neeg siv kawg. Ntawm qhov tod tes, cov teeb liab los ntawm cov neeg siv kawg raug xa mus rau ntau qhov kev pabcuam sib txuas raws li hom kev pabcuam. hauv.
POS (passive optical splitter)
Qhov no yooj yim to taub, uas yog faib cov ntaub ntawv downlink thiab sau cov ntaub ntawv uplink.
ONU(Optical Network Unit) / ONT (Khoom kho qhov muag Network Terminal)
Ntaus ze tshaj rau tus neeg siv. Ntau tus neeg tsis tuaj yeem paub qhov txawv ntawmONUthiab ONT. Qhov tseeb, qhov sib txawv yooj yim yog tias ONT yog homONU. ONT tsuas muaj ib qho chaw nres nkoj thiab ua haujlwm rau ib tus neeg siv.ONUpab ntau tus neeg siv. Lub teeb miv hauv peb tsev neeg yog ONT.
PON siv WDM (Wavelength Division Multiplexing, uas yog qhov sib faib ntau zaus, wavelength × zaus = ceev ntawm lub teeb) thev naus laus zis kom ua tiav ib leeg-fiber bidirectional kis tau tus mob nrog ib qho hluav taws xob nruab nrab ntawm 1310nm thiab downstream wavelength ntawm 1490nm.
PON muaj ntau yam zoo xws li kev siv bandwidth siab, kev ua haujlwm siab, kev pabcuam loj, thiab cov neeg siv khoom siv nplua nuj. Nws yog tam sim no nrov tshaj plaws optical access technology.
Raws li cov ntsiab lus ntawm tus tuav, PON feem ntau muab faib ua cov hauv qab no:
- ATM-raws li Passive Optical Network (APON)
- Ethernet (EPON) raws li Ethernet passive optical network (EPON)
- Gigabit Passive Optical Network (GPON) raws li GFP (General Framing Procedure)
Qhov tseeb, koj tsis tas yuav nco ntau npaum li ntawd. Txawm li cas los xij, nco ntsoov tias GPON yog qhov zoo tshaj plaws thiab qhov zoo tshaj plaws. Tam sim no txhua tus neeg ua haujlwm loj tau ua haujlwm hnyav los tsim GPON.
Graphical fiber-optic Internet txheej txheem
Tom qab hais lus ntev ntev, txhua tus yuav xav tias kiv taub hau me ntsis, cia peb siv cov xwm txheej tiag tiag thiab cov duab los piav qhia nws.
Peb pib los ntawm tus IP qaum network, los ntawm sab saum toj mus rau hauv qab, ib tug los ntawm ib tug.
Ua ntej tshaj plaws, lub npe hu ua Internet yog kom txaus siab rau cov kev pabcuam uas muab los ntawm cov neeg muab kev pabcuam network. Piv txwv li, siv WeChat kev pabcuam muab los ntawm Tencent, Taobao kev pabcuam muab los ntawm Ali, thiab kev pabcuam video muab los ntawm Youku.
Cov kev pabcuam no yog nyob ntawm cov tuam txhab cov servers hauv cov ntaub ntawv chaw.
Yog tias nws yog ib qho chaw ua lag luam cov ntaub ntawv, yuav muaj cov kab sib txuas los ntawm cov neeg ua haujlwm sib txawv. Los ntawm cov kab no, txuas mus rau lub teb chaws IP qaum network ntawm tus neeg teb xov tooj.
Lub teb chaws qaum teb network txuas nrog rau lub xeev qaum teb network. Lub xeev qaum teb network, thiab tom qab ntawd txuas mus rau lub nroog cheeb tsam network ntawm lub nroog. Tom qab cov kev xa mus los ntawm cov neeg nqa khoom network, thaum kawg tuaj rau hauv lub network nkag. Nov yog peb PON.
Tom qab tuaj txog ntawm PON, thawj kauj ruam yog nkag mus rauOLT.
CovOLTyog lub luag haujlwm rau ib cheeb tsam, ib lub tsev lossis thaj chaw nyob. Qhov no yog nyob ntawm tus naj npawb thiab qhov loj ntawm cov neeg siv. Rau thaj chaw muaj neeg coob coob xws li cov tsev ua haujlwm lossis tsev kawm ntawv, nws tseem tuaj yeem muab tso ncaj qha rau hauv lub tsev.
Optical fibers los ntawm cov khoomOLTcov khoom siv txuas nrog ntau lub tsev nyob hauv zej zog los ntawm ODF racks thiab optical xa thawv.
Nyob rau hauv lub tsev nyob elv zoo, zoo li yuav muaj lub teeb kais lub thawv, nyob rau hauv lub beam splitter.
Lub optical splitter tuaj yeem faib cov fiber ntau rau hauv ntau txoj hauv kev raws li qhov sib piv ntawm 1: 16 lossis 1: 32, npog cov neeg siv hauv pem teb sib xws (los yog ntau lub plag tsev).
Cov fibers optical los ntawm lub splitter nkag mus rau hauv cov tsev ntawm cov neeg nyob hauv.
Tom qab cov fiber ntau nkag mus, nws yuav txuas nrog lub thawv tsis muaj zog tam sim no hauv tsev.
Yuav muaj "lub teeb miv" hauv lub thawv uas tsis muaj hluav taws xob. Cov miv kho qhov muag no, raws li tau hais ua ntej, yog qhov tseeb ONT, tus neeg siv khoom siv fiber ntau nkag mus siv.
Ntu tom ntej yog paub zoo rau txhua tus, txhua tsev neeg yuav yuav lub wirelessrouter(uas yog, Wi-Firouter). Los ntawmrouter, txuas lub tshuab kho qhov muag kom hu xov tooj, thiab hloov cov teeb liab optical fiber ntau rau hauv koj lub tsev lub wireless network teeb liab, kom cov xov tooj ntawm tes, khoos phis tawj, iPads thiab lwm yam khoom siv nkag tau hauv Internet.
Cov saum toj no yog cov feem ntau raug kho qhov muag fiber broadband txoj kev nkag.
Txhua tus neeg pom tias nyob rau hauv cov ntaub ntawv saum toj no, cov fiber ntau optical txuas ncaj qha rau hauv tsev, qhov no yog hu ua FTTH (Fiber To The Home).
Txawm li cas los xij, rau ntau lub zej zog qub, cov cuab yeej siv hauv network tsis txaus kom ua tau raws li cov xwm txheej ntawm FTTH. Yog tias cov fiber ntau tsis tuaj yeem ncav cuag lub tsev, FTTB lossis FTTC yuav raug saws.
FTTB: Fiber rau Lub Tsev
FTTC: Fiber rau qhov Curb
Noj FTTB ua piv txwv, thaum cov fiber ntau optical los ntawmOLTdhau los ntawm ODF optical faib thav duab thiab splitter, thaum nws tuaj txog hauv lub tsev, nws ncaj qha nkag mus rau hauvONUhauv chav tsis muaj zog tam sim no ntawm lub tsev.
ONUmuaj ntau txoj kev nkag. Cias muab, nws yog hloov txoj kev kho qhov muag fiber ntau rau ADSL txoj kev, POTS txoj kev, thiab LAN txoj kev.
