Traditional nhare network izwi nedunhu kuchinjana, inodiwa yekufambisa Broadband ye64kbit/s.Iyo inodaidzwa kuti VoIP ndiyo IP packet exchange network senzvimbo yekutapurirana, iyo yakateedzerwa yezwi chiratidzo compression, kurongedza uye nhevedzano yeakakosha kugadzirisa, kuitira kuti ishandise isina kubatana UDP protocol yekutumira.
Zvinhu zvakati wandei uye mabasa anodiwa kufambisa masaini ezwi pane IP network.Iyo yakapfava fomu yetiweki ine maviri kana anopfuura maturusi ane VoIP hunyanzvi akabatana kuburikidza neIP network.
1.Voice-Data Shanduko
Chiratidzo chezwi isanalog waveform, kuburikidza neIP kuendesa izwi, ingave chaiyo-nguva application bhizinesi kana chaiyo-nguva application bhizinesi, kutanga kune izwi remasaini analog data shanduko, kureva iyo analog izwi chiratidzo 8 kana 6 quantification, yozotumirwa kune buffer kuchengetedza. , saizi yebhafa inogona kusarudzwa zvinoenderana nezvinodiwa zvekunonoka uye kukodha.Mazhinji akaderera bit rate encoder akaiswa encoded mumafuremu.
Yakajairika furemu kureba kubva pa10 kusvika ku30 ms.Tichifunga nezvemitengo panguva yekufambisa, mapaketi emitauro yakawanda anowanzo kuve ne60, 120, kana 240ms yedata rekutaura.Digitization inogona kuitwa pachishandiswa nzira dzakasiyana-siyana dzekodha yezwi, uye maitiro ekodha yezwi azvino ari kunyanya ITU-T G.711.Iyo encoder yezwi panzvimbo yainoenda inofanira kushandisa algorithm yakafanana kuitira kuti mudziyo wekutaura panzvimbo yaunoenda ugone kudzoreredza matauriro eanalogi.
2.Original data-to-IP kutendeuka
Kana chiratidzo chekutaura chaiswa kodhi, nhanho inotevera ndeyekumanikidza encode yekutaura pakiti ine yakatarwa furemu kureba.Mazhinji encoders ane chaiyo furemu kureba.Kana encoder ikashandisa 15ms mafuremu, iyo 60ms package kubva pekutanga inokamurwa kuita mana mafuremu uye encoded mukutevedzana.Imwe neimwe furemu ine zana nemakumi maviri ekutaura samples (sampling rate ye8kHz).Mushure me encoding, iwo mana akamisikidzwa mafuremu akagadzirwa kuita akamanikidzwa kutaura pasuru uye akatumirwa kune network processor.Iyo network processor inowedzera Baotou, chiyero chenguva, uye rumwe ruzivo kune izwi uye inopfuudza kune imwe magumo kuburikidza netiweki.
Iyo yekutaura network inongogadzira kubatana kwemuviri pakati penzvimbo dzekutaurirana (mutsetse mumwe) uye inotumira masaini encoded pakati pemagumo.Kusiyana nedunhu switching network, IP network haiumbe kubatana.Zvinoda kuti data iiswe mune akasiyana-siyana data data mishumo kana mapaketi, ipapo kero uye kutonga ruzivo kune yega yega datagiramu uye inotumirwa pamusoro petiweki, ichiendeswa kune kwainoenda.
3.Transfer
Muchiteshi ichi, network yese inoonekwa sepaketi yezwi inogamuchirwa kubva kune yekuisa uye yobva yaendeswa kune network inobuda mukati meimwe nguva (t).Iyo t inogona kusiyanisa muhuwandu hwakazara, ichiratidza jitter mune network kutapurirana.
Iyo imwechete node munetiweki inotarisa ruzivo rwekero rwakabatana neiyo yega IP data uye inoshandisa iyi ruzivo kuendesa iyo datagraph kune inotevera inomira munzira yekuenda.A network link inogona kuve chero topology kana nzira yekuwana inotsigira IP data hova.
4.I IP package- -shanduko yedata
Iyo yekuenda yeVoIP mudziyo inogamuchira iyi IP data uye inotanga kugadzirisa.Iyo network level inopa hurefu hwakasiyana buffer inoshandiswa kugadzirisa jitter inogadzirwa netiweki.Iyo buffer inogona kugarisa akawanda mazwi mapaketi, uye vashandisi vanogona kusarudza saizi yebuffer.Madiki mabhafa anoburitsa mashoma latency, asi haadzore hombe jitter.Chechipiri, iyo decoder inosunungura encoded yekutaura packet kuti ibudise nyowani yekutaura package, uye iyi module inogona zvakare kushanda nefuremu, yakanyatso hurefu hwakafanana neiyo decoder.
Kana iyo furemu kureba iri 15ms, iwo 60ms mapeketi ezwi anokamurwa kuita 4 mafuremu, uye anobva adzoserwa kumashure kune 60ms izwi rekuyerera kwedata uye anotumirwa kune decoding buffer.Munguva yekugadziriswa kweiyo data data, iyo kero uye yekudzora ruzivo inobviswa, iyo yepakutanga data inochengetwa, uye iyi yekutanga data inobva yapihwa kune decoder.
5.Digital kutaura kwakashandurwa kuita analog kutaura
Iyo yekuridza dhiraivha inobvisa masamples ezwi (480) mubuffer uye yoatumira kune kadhi rekurira kuburikidza nemutauri panguva yakatarwa (semuenzaniso 8kHz).Muchidimbu, kufambisa kwemasaini ezwi pa IP network kunopinda kuburikidza nekutendeuka kubva kuchiratidzo cheanalog kuenda kudhijitari, dhijitari izwi kurongedza muIP packet, IP packet transmission kuburikidza netiweki, IP packet unpacking uye kudzoreredzwa kwezwi redhijitari kune analog. chiratidzo.
Chechipiri, VoIP-inoenderana nehunyanzvi zviyero
Kumaapplications emultimedia pamanetiweki ekutaurirana aripo, International Telecommunication Union (ITU-T) yakagadzira H.32x Multimedia communication series protocol, zvinotevera mipimo mikuru yetsananguro iri nyore:
H.320, Standard for multimedia communication pane narrowband video phone system uye terminal (N-ISDN);
H.321, Chiyero chemultimedia kutaurirana paB-ISDN;
H.322.Yakajairwa kutaurirana kwemultimedia paLAN yakavimbiswa neQoS;
H.323.Yakajairwa yemultimedia kutaurirana pane packet switching network pasina QoS vimbiso;
H.324, chiyero chemultimedia kutaurirana pane yakaderera bit rate yekutaurirana zviteshi (PSTN uye network isina waya).
Pakati pezviyero zviri pamusoro apa, H. The 323 Standard-defined networks ndiyo inonyanya kushandiswa, yakadai seEthernet, Token Network, FDDI Network, etc.nekuda kweH.Kushandiswa kwe323 chiyero chave chave chave chiri kupisa nzvimbo pamusika, saka pazasi tichatarisa paH.323。H.323 Zvikamu zvina zvikuru zvinotsanangurwa muchikumbiro: terminal, gedhi, gedhi manejimendi software (inozivikanwawo segedhi kana gedhi), uye multi-point control unit.
1.Terminal (Terminal)
Zvose zviteshi zvinofanirwa kutsigira kutaurirana kwezwi, uye mavhidhiyo nedata zvekutaura zvinogoneka ndezvekusarudza.Zvose H.The 323 terminal inofanirawo kutsigira H.245 Standard, H.245 Chiyero chinoshandiswa kudzora mashandisirwo echiteshi uye kuita kwechiteshi.H .323 Mitemo mikuru yekodheki yekutaura mukukurukurirana kwezwi inotsanangurwa sezvinotevera: ITU inokurudzirwa inzwi bandwidth / KHz transmission bit rate / Kb/s compression algorithm annotation G.711 3.4 56,64 PCM nyore kudzvanya, inoshandiswa kuPSTN muG .728 3.4 16 LD-CELP inzwi remhando yeG.711, sekushandiswa kune yakaderera-bit-rate kutapurirana G.722 7 48,56,64 ADPCM inzwi remhando yepamusoro kupfuura G.711, rinoiswa kuhigh bit rate transmission G. . G.723.1.
2.Gateway (Gateway)
Iyi iH.An sarudzo ye 323 system. Gedhi rinogona kushandura maprotocol, audio, video coding algorithms uye zviratidzo zvekutonga zvinoshandiswa nemaitiro akasiyana-siyana kuti agadzirire hurongwa hwehutano hwekukurukurirana.Sezvakaita PSTN-based of H.324 System uye narrowband ISDN-based H.The 320 System uye H.323 Pakukurukurirana kwehurongwa, zvakakosha kugadzirisa gedhi;
3.Kuchengeta tsika (Muchengeti wegedhi)
Ichi ndicho H.An optional component ye 323 system ndiyo software yekupedzisa basa rekutungamirira.Iine mabasa maviri makuru: yekutanga ndeye H.323 Application management;chechipiri ndiyo hutungamiri hwekutaurirana kwekupedzisira kuburikidza negedhi (zvakadai sekusikwa kwefoni, kubvisa, nezvimwewo) .Vatungamiri vanogona kuita shanduko yekero, bandwidth control, call authentication, call recording, user registration, communication domain management uye mamwe mabasa kuburikidza netsika. kuchengeta.one H.323 Nzvimbo yekukurukurirana inogona kuva nemasuwo akawanda, asi gedhi rimwe chete rinoshanda.
4.Multipoint control unit (Multipoint Control Unit)
Iyo MCU inogonesa kutaurirana kwakasiyana-siyana pane IP network, uye kunongedzera-ku-point kutaurirana hakudiwi.Sitimu yese inoumba nyeredzi topology kuburikidza neMCU.The MCU ine zvikamu zviviri zvikuru: multipoint controller MC uye multipoint processor MP, kana pasina M.H pakati pe MC processing terminals.245 Chengetedza ruzivo kuti uvake zita shoma reruzhinji kuti rigadziriswe odhiyo nemavhidhiyo.MC haigadzirise zvakananga chero chero nhepfenyuro yenhau, asi inoisiya kuMP. MP inosanganisa, inochinja, uye kugadzirisa odhiyo. , vhidhiyo, kana ruzivo rwedata.
Muindasitiri mune zvivakwa zviviri zvakafanana, imwe iITU-T H yakaunzwa pamusoro.323 Protocol ndiyo SIP protocol (RFC2543) inokurudzirwa neInternet Engineering Task Force (IETF), uye SIP protocol inonyanya kufanirwa kune materminal akangwara.
Chechitatu, Kukurudzira kweVoIP budiriro
Kushandiswa kwakapararira kweVoIP kuchakurumidza kuzadzikiswa nekuda kwezvizhinji zvehardware, software, zvinechekuita nebudiriro uye tekinoroji muprotocol uye zviyero.Kufambira mberi kwehunyanzvi uye kusimukira mundima idzi kunoita basa rekufambisa mukugadzira network yeVoIP inoshanda zvakanyanya, inoshanda uye inobatanidza. Iyo tekinoroji zvinhu zvinosimudzira kukurumidza kusimudzira uye kunyangwe kupararira kushandiswa kweVoIP kunogona kupfupikiswa mune zvinotevera zvinhu.
1.Digital Signal processor
Advanced digital signal processors (Digital Signal Processor, DSP) inoita computation-intensive computation inodiwa pakubatanidza izwi nedata.DSP inoshandisa masignal signals kuti iite zviverengero zvakaoma dzingangofanira kuitwa neCPU yepasirese.Kusanganiswa kwehunyanzvi hwavo. kushandiswa kwesimba nemutengo wakaderera kunoita kuti DSP inyatsokodzera kuita masaini ekugadzirisa mabasa muVoIP system.
Single voice stream paG.729 The computing cost of voice compression inowanzokura, inoda 20MIPS.Kana iyo yepakati CPU ichidikanwa kuita routing uye system manejimendi mabasa uchigadzira akawanda manzwi enzizi, izvi hazvigoneke.Naizvozvo, kushandisa imwe kana kupfuura DSP inogona kusunungura komputa basa reiyo yakaoma izwi compression algorithm kubva pakati peCPU.Mukuwedzera, DSP yakakodzera kuona chiitiko chezwi uye kudzima echo, ichivabvumira kugadzirisa dhata re data munguva chaiyo uye nekukurumidza kuwana. pa-board memory, so.Muchikamu chino, tinodonongodza maitiro ekuita voice coding uye echo kudzima paTMS320C6201DSP platform.
Protocol and standard software and hardware H.323 Weighted fair queuing method DSP MPLS tag kuchinjana kuyerwa zvisina tsarukano kukurumidza kuonekwa advanced ASIC RTP, RTCP dual funnel general cell rate algorithm DWDM RSVP rated access fast rate SONET Diffserv, CAR Cisco fast forwarding CPU processing power G. 729, G.729a: CS-ACELP Yakawedzerwa Access Table ADSL, RADSL, SDSL FRF.11/FRF.12 Token barrel algorithm Multilink PPP Frame Relay Data rectifier SIP inobva pakubatanidzwa kwekutanga kweCoS Packet pamusoro peSONET IP uye ATM QoS / CoS
2.Advanced yakatsaurirwa matunhu akabatanidzwa
Iyo Application-Specific Integrated Circait (ASIC) budiriro yakagadzira inokurumidza, yakanyanya kuomarara, uye inoshanda zvakanyanya ASIC.ASIC inyanzvi yekushandisa chip inoita imwechete application kana seti diki yemabasa. anogona kuve akagadziridzwa zvakanyanya kune chaiwo mabasa, kazhinji aine mbiri-chinangwa CPU imwe kana akati wandei maodha ehukuru nekukurumidza.
Sezvakangoita Thin Instruction set Computer (RSIC) chip inotarisa pakukurumidza kuurayiwa kwenhamba dzemuganhu, ASIC inofanorongwa kuti iite nhamba inogumira yemabasa nokukurumidza.Kana kubudirira kwapera, mutengo weASIC kugadzirwa kwehuwandu hwakaderera, uye inoshandiswa. kune network network zvinosanganisira ma routers uye switch, kuita mabasa akadai sekutarisa tafura yekutarisa, kutumira kweboka, kuronga boka uye kutarisa, uye queuing.Kushandiswa kweASIC kunopa chigadziriso chepamusoro uye mari shoma.Vanopa yakawedzera Broadband uye nani QoS rutsigiro rweiyo network, saka vanoita basa guru mukusimudzira budiriro yeVoIP.
3.IP tekinoroji yekutumira
Mazhinji ekutepfenyura telecom network anoshandisa nguva-kupatsanura kuwanda, nepo iyo Internet inofanirwa kutora nhamba yekushandisa zvakare uye refu packet exchange.Zvichienzaniswa, iyo yekupedzisira ine yakakwirira yekushandiswa kwehuwandu hwemambure ezviwanikwa, nyore uye inobudirira kubatanidza, uye inoshanda zvakanyanya kune data masevhisi, chinova chimwe chezvikonzero zvakakosha zvekukurumidza kukura kweInternet.Zvisinei, Broadband IP network network inoda QoS uye kunonoka maitiro. Parizvino, kuwedzera kuchizvarwa chitsva che IP protocol-IPV6, boka repasi rose reInternet engineering task group (IETF) rakaronga multi-protocol tag exchange technology (MPLS), iyi. imhando yetiweki layer yekusarudza yakavakirwa akasiyana tag / label exchange, inogona kuvandudza kuchinjika kwekusarudzwa kwemugwagwa, kuwedzera network layer yekusarudza kugona, kurerutsa iyo router uye chiteshi chekuchinjana kusanganisa, kunatsiridza mashandiro etiweki.MPLS inogona kushanda seyakazvimirira routing protocol, uye inoenderana neiyo iripo network routing protocol, inotsigira akasiyana mashandiro, manejimendi uye kugadzirisa mabasa eIP network, ita iyo QoS, routing, kusaina kuita kwakagadziridzwa zvakanyanya, kusvika kana pedyo nedanho rekushandisazve nhamba yakatarwa kureba packet exchange (ATM), uye iri nyore, inoshanda, yakachipa uye inoshanda pane ATM.
IETF zvakare iri munharaunda kubata tekinoroji yemapoka matsva, kuitira kuti iwane kusarudzwa kwenzira yeQoS. "Tekinoroji yetunnel" iri kudzidzwa kuti iwane kufambiswa kwebroadband yenzira imwe chete. Uyezve, nzira yekusarudza IP network network transmission platform zvakare nzvimbo inokosha yekutsvakurudza mumakore achangopfuura, uye IP pamusoro peATM, IP pamusoro peSDH, IP pamusoro peDWDM nemamwe matekinoroji akaonekwa achitevedzana.
Iyo IP layer inopa vashandisi veIP yepamusoro-mhando ye IP yekuwana masevhisi ane mamwe masevhisi anovimbisa.Mushandisi layer inopa fomu rekupinda (IP access uye Broadband access) uye fomu remukati sevhisi.Muchikamu chekutanga, Ethernet, sechikamu chemuviri iyo IP network, inyaya yechokwadi, asi IP overDWDM ine tekinoroji yazvino, uye ine mukana mukuru webudiriro.
Dense Wave Division MultipLexing (DWDM) inopinza hupenyu hutsva mumafiber network uye inopa bandwidth inoshamisa mumakambani efoni anoisa fiber itsva backbone.DWDM teknolojia inoshandisa kukwanisa kweoptical fibers uye advanced optical transmission equipment.Zita rekuti wave division multiplexing rinotorwa pakutumira akawanda wavelengths yechiedza (LASER) kubva kune imwe rwizi rwefiber optical.Masisitimu emazuva ano anogona kutumira uye kuziva 16 wavelengths, nepo zvirongwa zveramangwana zvinogona kutsigira 40 kusvika 96 yakazara wavelengths.Izvi zvakakosha nekuti imwe neimwe yavelength inowedzera inowedzera kuwedzera kweruzivo. saka wedzera iyo 2.6 Gbit / s (OC-48) network ne16 nguva pasina kuisa ma fiber matsva.
Mazhinji mafiber network matsva anomhanyisa OC-192 pa (9.6 Gbit / s), achigadzira simba pamusoro pe150 Gbit / s pane peya yefiber kana yasanganiswa neDWDM.Pakuwedzera, DWDM inopa interface protocol uye nekukurumidza-yakazvimirira maitiro, uye inotsigira ese maATM. , SDH uye Gigabit Ethernet chiratidzo chekufambisa pane imwe fiber, iyo inogona kuwirirana nemagetsi aripo, saka DWDM inogona kuchengetedza zvinhu zviripo, asiwo inopa ISP uye makambani efoni ane simba remusana, uye kuita kuti Broadband isingadhuri uye inowanikwa, iyo inopa rutsigiro rwakasimba kune bandwidth zvinodiwa zveVoIP mhinduro.
Iyo yakawedzera yekufambisa mwero haingogone kupa pombi yakaomarara ine mukana mudiki wekuvharira, asi zvakare kuderedza kunonoka nekuwanda, uye nekudaro kunogona kuderedza zvakanyanya zvinodikanwa zveQoS paIP network.
4.Broadband kuwana teknolojia
Kusvika kwemushandisi weIP network kwave kuvharisa kuvharidzira kukudziridzwa kwese network.Munguva refu, chinangwa chekupedzisira chekusvika kwemushandisi ndeye fiber-to-home (FTTH) .Pakutaura, optical access network inosanganisira optical digital loop carrier system. uye passive optical network.Iyo yekare inonyanya kuUnited States, yakasanganiswa nemuromo wakashama V5.1 / V5.2, inotumira maitiro ayo akabatanidzwa pane optical fiber, ichiratidza simba guru.
Iyo yekupedzisira inonyanya kurongeka uye muGermany.Kweanopfuura makore gumi, Japan yakatora matanho ekuderedza mutengo we passive optical network kusvika pamwero wakafanana netambo dzemhangura nesimbi yakamonyoroka peya, uye yakaishandisa kushandisa.Kunyanya mumakore achangopfuura, ITU yakaronga iyo ATM-based passive optical network (APON), iyo inozadzisa zvakanakira ATM uye passive optical network.Chiyero chekuwana chinogona kusvika 622 M bit / s, iyo inobatsira zvikuru mukugadzirwa kwebroadband IP multimedia service, uye inogona kuderedza kukundikana kwehuwandu uye nhamba yemanodhi, uye kuwedzera kuvharidzirwa.Parizvino, ITU yakapedza basa rekuenzanisa. , vagadziri vari kushingaira kusimudzira, pachava nezvinhu pamusika, ichave iyo huru yekusimudzira nzira yebroadband yekuwana tekinoroji yezana ramakore re21.
Parizvino, iyo huru yekuwana matekinoroji ndeiyi: PSTN, IADN, ADSL, CM, DDN, X.25 uye Ethernet uye Broadband wireless access system column, etc.Idzi tekinoroji dzekuwana dzine maitiro avo, kusanganisira inokurumidza kukura ADSL neCM;CM (Cable Modem) inoshandisa coaxial cable, high transmission rate, simba rinopesana nekupindira;asi kwete nzira mbiri, hapana yunifomu mwero.ADSL (Asymmetrical Digital Loop) ine mukana wakasarudzika kune Broadband, ichishandisa zvizere network iripo yefoni uye kupa asymmetric transmission rate.Nhamba yekurodha padivi remushandisi inogona kusvika 8 Mbit / s, uye chiyero chekukwirisa padivi remushandisi chinogona kusvika 1M bit / s.ADSL inopa Broadband inodiwa yebhizinesi nevashandisi vese, uye inoderedza zvakanyanya mutengo.Kushandisa yakaderera-mutengo ADSL matunhu ematunhu, makambani ave kuwana Internet uye Internet-yakavakirwa VPN nekumhanya kwepamusoro, ichibvumira yakakwira VoIP yekufona.
5.Central processing unit teknolojia
Central processing units (CPU) inoramba ichishanduka mukushanda, simba, uye kukurumidza.Izvi zvinogonesa kushandiswa kwakapararira kwemultimedia PC uye inovandudza mashandiro ehurongwa hwemabasa akaganhurirwa neCPU simba.Kugona kwePC kugadzira dhata redhidhiyo nevhidhiyo yakamirirwa kwenguva refu. nevashandisi, saka kuendesa kufona kwezwi pamanetiweki edata ndiyo inongove chinangwa chinotevera.Ichi chimiro chekombuta chinogonesa ese ari maviri epamusoro multimedia desktop desktop uye maficha epamusoro muzvikamu zvetiweki kutsigira maapplication ezwi.