Vim muaj ntau yam kev txhim kho thiab kev ua haujlwm thev naus laus zis hauv cov khoom siv sib xws, software, cov txheej txheem thiab cov qauv, kev siv VoIP dav yuav dhau los ua qhov tseeb. Kev txhim kho thev naus laus zis thiab kev txhim kho hauv cov cheeb tsam no tau pab tsim kom muaj txiaj ntsig zoo dua, ua haujlwm tau zoo, thiab sib cuam tshuam VoIP network. Cov txheej txheem kev tshaj lij uas txhawb txoj kev loj hlob sai thiab txawm tias daim ntawv thov dav dav ntawm VoIP tuaj yeem raug sau tseg rau hauv cov hauv qab no.
1, Digital Signal Processor
Advanced Digital Signal processors (DSPS) ua cov kev ua haujlwm hnyav uas yuav tsum tau ua rau lub suab thiab cov ntaub ntawv sib koom ua ke.DSP kev ua haujlwm ntawm cov teeb liab digital feem ntau yog siv los ua cov kev suav tsis yooj yim uas yuav tsum tau ua los ntawm lub hom phiaj dav dav CPU. Lawv lub zog ua haujlwm tshwj xeeb ua ke nrog tus nqi qis ua rau DSPS zoo haum rau kev ua cov teeb liab ua haujlwm hauv VoIP systems.
Kev suav nyiaj siv ua haujlwm ntawm G.729 hais lus compression ntawm ib lub suab kwj feem ntau yog loj, uas yuav tsum tau 20MIPS. Yog hais tias lub hauv paus CPU yuav tsum tau ua ntau lub suab kwj, ua routing thiab system tswj kev ua haujlwm tib lub sijhawm, nws tsis muaj tseeb. Yog li, kev siv ib lossis ntau dua DSPS tuaj yeem tshem tawm cov haujlwm ua haujlwm ntawm kev hais lus nyuaj compression algorithm nyob rau hauv nws los ntawm lub hauv paus CPU. Tsis tas li ntawd, DSPS kuj tsim nyog rau lub suab ua haujlwm nrhiav thiab ncha tshem tawm haujlwm, yog li lawv tuaj yeem ua cov ntaub ntawv suab. kwj hauv lub sijhawm tiag tiag thiab muaj kev nkag tau sai rau lub cim xeeb ntawm lub nkoj .Yog li, Hauv tshooj no, yuav ua li cas siv cov lus coding thiab ncha tshem tawm ntawm TMS320C6201DSP platform yog qhia kom ntxaws.
Cov txheej txheem thiab cov qauv Software thiab kho vajtse H.323 Qhov hnyav ncaj ncees queuing txoj kev DSP MPLS daim ntawv lo hloov qhov hnyav random thaum ntxov tshawb pom Advanced ASIC RTP, RTCP Ob Chav Funnel Universal Cell rate algorithm DWDM RSVP rated nkag Rate SONET Diffserv, CAR Cisco Fast Forwarding CPU Processing fais fab G.729 , G.729a:CS-ACELP Extended Access Table ADSL, RADSL, SDSL FRF.11/FRF.12 token thoob algorithm Multilink PPP Ncej Relay cov ntaub ntawv rectification SIP Kev koom ua ke ntawm qhov tseem ceeb-raws li CoS Pob ntawv hla SONET IP thiab ATM QoS/CoS
2 、 Advanced integrated circuits
Txoj kev loj hlob ntawm Application-Specific Integrated Circait (ASIC) tau ua kom nrawm dua, nyuaj dua thiab ua haujlwm zoo dua ASIC. Asics yog tshwj xeeb daim ntawv thov chips uas ua tiav ib daim ntawv thov lossis ib pawg me me ntawm kev ua haujlwm. Los ntawm kev tsom mus rau lub hom phiaj ntawm daim ntawv thov nqaim, lawv tuaj yeem ua kom zoo rau ib qho kev ua haujlwm tshwj xeeb thiab feem ntau yog ib lossis ob peb qhov kev txiav txim siab sai dua Ib yam li cov lus qhia txo qis (RSIC) chips tsom mus rau kev ua haujlwm tsawg tsawg, ASICS yog preprogrammed. txhawm rau ua kom muaj tsawg tsawg ntawm kev ua haujlwm sai dua. Ib zaug tsim, ASIC loj ntau lawm tsis kim thiab yog siv rau network li xws liroutersthiab keyboards, ua routing table checking, grouping forwarding, grouping sorting and checking, thiab queuing. Kev siv ASIC muab cov cuab yeej ua haujlwm siab dua thiab tus nqi qis dua. Lawv muab kev nthuav dav ntxiv thiab kev txhawb nqa QoS zoo dua rau lub network, yog li lawv ua lub luag haujlwm zoo hauv kev txhawb nqa VoIP txoj kev loj hlob.
3, IP kis tau tus mob technology
Feem ntau ntawm kev sib txuas lus hauv xov tooj sib txuas siv lub sij hawm faib ua ntau hom, thaum Is Taws Nem yuav tsum tau txais cov ntaub ntawv rov siv dua thiab ntev pob ntawv pauv hom. Piv nrog rau ob, tom kawg muaj kev siv ntau ntawm kev siv network, kev sib txuas lus yooj yim thiab siv tau zoo thiab kev sib txuas lus, thiab yog qhov tsim nyog rau cov ntaub ntawv cov kev pabcuam, uas yog ib qho tseem ceeb rau kev loj hlob sai ntawm Internet. Txawm li cas los xij, broadband IP network kev sib txuas lus muab tso rau qhov yuav tsum tau ua rau QoS thiab ncua cov yam ntxwv, yog li kev txhim kho ntawm cov ntaub ntawv sib txawv ntawm qhov sib txawv ntawm qhov ntev ntawm pob ntawv hloov tshuab tau nyiam cov neeg nyiam. Tam sim no, ntxiv rau tiam tshiab ntawm IP raws tu qauv-ipv6, Lub Ntiaj Teb Internet Engineering Task Force (IETF) tau tshaj tawm Multi-protocol Label Switching thev naus laus zis (MPLS), uas yog hom ntawv cim npe hloov tshuab raws li txheej txheej network. routing, uas tuaj yeem txhim kho qhov hloov pauv ntawm kev sib txuas, txuas ntxiv lub network txheej routing muaj peev xwm, ua kom yooj yim rau kev sib koom ua ke ntawmroutersthiab hloov cell. Txhim kho Network Performance. MPLS tuaj yeem tsis tsuas yog ua haujlwm raws li tus txheej txheem kev ua haujlwm ywj pheej, tab sis kuj tseem ua tau zoo nrog cov txheej txheem kev sib txuas uas twb muaj lawm. Nws txhawb ntau yam kev ua haujlwm, kev tswj hwm thiab kev saib xyuas kev ua haujlwm ntawm IP network, thiab txhim kho QoS, routing thiab signaling kev ua tau zoo ntawm IP network kev sib txuas lus, mus txog los yog nce qib ntawm statistical multiplexed Fixed Length packet switching (ATM). Nws yooj yim dua, ua tau zoo dua, pheej yig dua thiab siv tau ntau dua li ATM.
IETF tseem tab tom ua haujlwm ntawm cov txheej txheem tswj cov pob ntawv tshiab nyob rau hauv qhov chaw kom pab QoS routing. Tunneling thev naus laus zis tau kawm txhawm rau txhawm rau ua tiav kev sib kis dav dav hla kev sib txuas unidirectional. Tsis tas li ntawd, yuav ua li cas xaiv tus IP network kis tau tus mob platform kuj yog ib qho tseem ceeb ntawm kev tshawb fawb nyob rau hauv xyoo tas los no, thiab IP tshaj ATM, IP dhau SDH, IP dhau DWDM thiab lwm yam technologies tau tshwm sim successively.
IP txheej muab cov kev pabcuam zoo IP nkag nrog qee qhov kev pabcuam lav rau cov neeg siv IP. Cov neeg siv txheej muab daim ntawv nkag mus (IP nkag mus thiab nkag mus siv dav dav) thiab cov ntsiab lus kev pabcuam.Nyob hauv txheej txheej, Ethernet yog lub cev txheej ntawm IP network, nws yog ib qho teeb meem ntawm chav kawm, tab sis IP overDWDM yog cov thev naus laus zis tshiab, thiab muaj txiaj ntsig zoo. kev loj hlob muaj peev xwm.
Dense Wave Division MultipLexing (DWDM) tau ua pa lub neej tshiab rau hauv cov tes hauj lwm fiber ntau thiab muab cov bandwidth zoo kawg nkaus hauv cov tuam txhab xov tooj 'cov xov tooj tshiab tshiab. DWDM thev naus laus zis siv lub peev xwm ntawm optical fibers thiab cov khoom siv kho qhov muag kis tau zoo. Lub npe ntawm yoj division multiplexing yog muab los ntawm kev sib kis ntawm ntau lub wavelengths ntawm lub teeb (LASER) los ntawm ib txoj hlua ntawm ib qho fiber ntau optical. Cov tshuab tam sim no muaj peev xwm xa thiab txheeb xyuas 16 wavelengths, thaum lub tshuab yav tom ntej tuaj yeem txhawb nqa 40 txog 96 tag nrho wavelengths. Qhov no yog qhov tseem ceeb vim tias txhua qhov wavelength ntxiv ntxiv cov ntaub ntawv ntws ntxiv. Yog li 2.6 Gbit / s (OC-48) network tuaj yeem nthuav dav 16 zaug yam tsis tas yuav nteg cov fibers tshiab.
Feem ntau cov xov tooj tshiab fiber ntau khiav OC-192 ntawm (9.6 Gbit / s), ua kom muaj peev xwm tshaj 150 Gbit / s ntawm ib khub ntawm fibers thaum ua ke nrog DWDM. Tsis tas li ntawd, DWDM muab cov txheej txheem sib txuas thiab ceev cov yam ntxwv ywj pheej, hauv fiber ntau tau txhawb nqa ATM, SDH thiab Gigabit Ethernet teeb liab kis tau tus mob tib lub sijhawm, yog li nws tuaj yeem sib haum nrog ntau lub network uas tau tsim tam sim no, yog li DWDM tuaj yeem tsis tsuas yog tiv thaiv cov txheej txheem uas twb muaj lawm, tab sis kuj tuaj yeem muab cov pob txha muaj zog dua rau ISP. thiab tuam txhab lag luam telecom nrog nws cov bandwidth loj. Thiab ua kom broadband pheej yig dua thiab siv tau ntau dua, uas muab kev txhawb nqa muaj zog rau cov kev cai bandwidth ntawm VoIP cov kev daws teeb meem.
Qhov kev sib kis tau nce ntxiv tuaj yeem tsis tsuas yog muab cov kav dej tuab dua uas muaj feem tsawg ntawm kev thaiv, tab sis kuj tseem ua rau qhov ncua sij hawm qis dua, thiab yog li ntawd tuaj yeem txo qis QoS cov cai ntawm IP tes hauj lwm mus rau qhov loj.
4. Kev siv tshuab dav dav
Cov neeg siv kev nkag mus ntawm IP network tau dhau los ua ib qho kev txwv tsis pub muaj kev loj hlob ntawm tag nrho lub network. Nyob rau hauv lub sij hawm ntev, lub hom phiaj ntawm qhov kawg ntawm cov neeg siv yog fiber-to-the-tsev (FTTH). Hais lus dav dav, optical access network suav nrog optical digital loop carrier system thiab passive optical network. Lub qub yog nyob rau hauv lub tebchaws United States, ua ke nrog qhib lub qhov ncauj V5.1/V5.2, kis tau nws cov kev koom ua ke system ntawm optical fiber, uas qhia tau hais tias tseem ceeb heev. Cov tom kawg yog nyob rau hauv Nyiv thiab lub teb chaws Yelemees. Nyiv tau mob siab rau hauv kev tshawb fawb rau ntau tshaj kaum xyoo, thiab tau ua ntau yam kev ntsuas los txo tus nqi ntawm kev sib txuas lus kho qhov muag mus rau qib zoo sib xws nrog cov tooj liab cables thiab hlau sib tw-pair xov hlau, thiab siv ntau yam. Tshwj xeeb tshaj yog nyob rau hauv xyoo tas los no, ITU tau npaj ATM raws li Passive optical Network (APON), uas sib txuas qhov zoo ntawm ATM thiab passive optical network. Tus nqi nkag tuaj yeem ncav cuag 622M ntsis / s, uas muaj txiaj ntsig zoo rau kev txhim kho cov kev pabcuam broadband IP multimedia, thiab tuaj yeem txo qis tus nqi tsis ua haujlwm thiab tus naj npawb ntawm cov nodes, thiab nthuav dav qhov kev pabcuam. Tam sim no, ITU tau ua tiav cov txheej txheem kev ua haujlwm, thiab ntau lub tuam txhab tsim khoom tsim tawm. Tsis ntev tom ntej no yuav muaj cov khoom lag luam hauv kev lag luam, thiab nws yuav dhau los ua txoj kev loj hlob tseem ceeb ntawm kev siv broadband nkag mus rau hauv lub xyoo pua 21st.
Tam sim no, cov cuab yeej siv tseem ceeb yog: PSTN, IADN, ADSL, CM, DDN, X.25, Ethernet thiab broadband wireless access system. Cov kev siv thev naus laus zis no muaj lawv tus kheej cov yam ntxwv, cov kev txhim kho sai tshaj plaws yog ADSL thiab CM; CM (Cable Modem) txais yuav coaxial cable nrog kev sib kis tau zoo thiab muaj zog tiv thaiv kev cuam tshuam; tab sis tsis yog ob txoj kev sib kis, tsis muaj kev sib koom ua ke.
ADSL (Asymmetrical Digital Loop) muab tshwj xeeb rau kev nkag mus rau broadband, siv tag nrho cov xov tooj uas twb muaj lawm, thiab muab tus nqi sib kis asymmetric. Tus nqi rub tawm ntawm tus neeg siv sab tuaj yeem ncav cuag 8 Mbit / s, thiab tus nqi upload ntawm tus neeg siv tuaj yeem ncav cuag 1M ntsis / s. ADSL muab qhov tsim nyog broadband rau cov lag luam thiab cov neeg siv ib leeg, thiab txo cov nqi ntau heev. Siv cov nqi qis ADSL hauv cheeb tsam, cov tuam txhab tam sim no tuaj yeem nkag mus rau Is Taws Nem thiab Is Taws Nem muab kev pabcuam raws li VPN ntawm qhov nrawm dua, ua rau muaj peev xwm hu VoIP ntau dua.
5. Central processing unit technology
Central processing units (cpus) txuas ntxiv mus rau hauv cov nqe lus ntawm kev ua haujlwm, lub zog, thiab ceev. Qhov no ua rau multimedia PCS tau siv dav thiab txhim kho kev ua haujlwm ntawm cov haujlwm uas raug txwv los ntawm CPU lub zog. Lub peev xwm ntawm PCS los tswj streaming audio thiab video cov ntaub ntawv tau ntev lawm xav tau los ntawm cov neeg siv, yog li xa lub suab hu rau cov ntaub ntawv sib txuas yog qhov laj thawj tom ntej. Qhov kev muaj peev xwm ntawm kev suav no ua rau ob qho tib si cov ntawv thov multimedia desktop siab heev thiab cov yam ntxwv siab heev hauv cov khoom siv hauv network los txhawb cov ntawv thov suab.
VOIP belongs rau pebONUseries network cov khoom lag luam hauv kev lag luam, thiab cov khoom lag luam kub network ntawm peb lub tuam txhab npog ntau homONUseries, suav nrog ACONU/ kev sib txuas lusONU/ ntseONU/ lub thawvONU/ ob lub PON chaw nres nkojONU, lwm.
Cov saum toj noONUseries cov khoom siv tuaj yeem siv rau cov kev cai network ntawm ntau yam xwm txheej. Txais tos kom muaj kev nkag siab ntau ntxiv txog cov khoom.
