Inethiwekhi yomnxeba yemveli lilizwi ngokutshintshiselana kwesekethe, ibroadband efunekayo yothumelo lwe-64kbit/s.I-VoIP ebizwa ngokuba yi-IP yenethiwekhi yepakethi yokutshintshiselana njengeplatifomu yokuhambisa, ukunyanzeliswa kwelizwi elifanisiweyo, ukupakishwa kunye nochungechunge lwenkqubo ekhethekileyo, ukwenzela ukuba isebenzise i-protocol ye-UDP engaxhunywanga yokuhanjiswa.
Izinto ezininzi kunye nemisebenzi efunekayo ukuhambisa iimpawu zelizwi kwinethiwekhi ye-IP.Eyona ndlela ilula yothungelwano iqulethe izixhobo ezibini okanye ngaphezulu ezinezakhono zeVoIP ezidityaniswe ngenethiwekhi ye-IP.
1.Ukuguqulwa kweVoice-Data
Isignali yelizwi yi-analog waveform, nge-IP ukuhambisa ilizwi, nokuba ishishini lesicelo sexesha lokwenyani okanye ishishini lesicelo sexesha lokwenyani, okokuqala kwilizwi lokuguqulwa kwedatha ye-analog, oko kukuthi i-analog voice signal 8 okanye i-6 quantification, kwaye emva koko ithunyelwe kwindawo yokugcina i-buffer. , ubungakanani besikhuseli bunokukhethwa ngokweemfuno zokulibaziseka kunye nekhowudi.Iikhowudi ezininzi ezisezantsi zifakwe kwiikhowudi kwizakhelo.
Ubude besakhelo esiqhelekileyo busuka kwi-10 ukuya kwi-30 ms.Ukuqwalasela iindleko ngexesha lokudluliselwa, iipakethi zeelwimi eziqhelekileyo ziquka i-60, i-120, okanye i-240ms yedatha yentetho.I-Digitization ingaphunyezwa ngokusebenzisa izikimu zekhowudi ezahlukeneyo zelizwi, kwaye imigangatho yekhowudi yangoku yelizwi ikakhulu i-ITU-T G.711.I-encoder yelizwi kwindawo ekuyiwa kuyo kufuneka isebenzise i-algorithm efanayo ukuze isixhobo sokuthetha kwindawo ekusingise kuyo sibuyisele umqondiso wentetho ye-analog.
2.Original data-to-IP ukuguqulwa
Nje ukuba umqondiso wentetho ukhowudwe ngokwedijithali, inyathelo elilandelayo kukucinezela ikhowudi yepakethi yentetho enobude obuthile besakhelo.Uninzi lweekhowudi zinobude obuthile besakhelo.Ukuba i-encoder isebenzisa iifreyimu ze-15ms, iphakheji ye-60ms ukusuka kwindawo yokuqala yohlulwe ibe yizakhelo ezine kwaye ifakwe ngekhowudi ngokulandelelana.Isakhelo ngasinye sineesampulu zentetho ezili-120 (umlinganiselo wesampulu ye-8kHz).Emva kokufakwa kweekhowudi, iifreyimu ezine ezicinezelweyo zadityaniswa kwiphakheji yentetho ecinezelweyo kwaye yathunyelwa kwiprosesa yenethiwekhi.Iprosesa yenethiwekhi yongeza i-Baotou, isikali sexesha, kunye nolunye ulwazi kwilizwi kwaye idlulisele kwelinye isiphelo kwinethiwekhi.
Inethiwekhi yentetho ibeka nje uxhulumaniso lomzimba phakathi kwee-endpoints zonxibelelwano (umgca omnye) kwaye idlulisa imiqondiso ekhowudiweyo phakathi kwee-endpoints.Ngokungafaniyo neenethiwekhi zokutshintsha kweesekethe, iinethiwekhi ze-IP azenzi unxibelelwano.Ifuna ukuba idatha ibekwe kwiingxelo eziguquguqukayo zedatha ende okanye iipakethi, emva koko idilesi kunye nokulawula ulwazi kwidathagram nganye kwaye ithunyelwe ngenethiwekhi, idluliselwe kwindawo ekuyiwa kuyo.
3.Ukudluliselwa
Kweli jelo, inethiwekhi iyonke ijongwa njengepakethi yelizwi efunyenwe kwigalelo kwaye emva koko idluliselwe kwimveliso yenethiwekhi ngexesha elithile (t).I-t inokwahluka kuluhlu olupheleleyo, ebonisa i-jitter kuthumelo lwenethiwekhi.
I-node efanayo kuthungelwano ihlola ulwazi lwedilesi oluhambelana nedatha nganye ye-IP kwaye isebenzisa olu lwazi ukuhambisa loo datagram kwindawo elandelayo yokumisa kwindlela ekuyiwa kuyo.Ikhonkco yenethiwekhi ingaba nayiphi na i-topology okanye indlela yokufikelela exhasa imilambo yedatha ye-IP.
4.Iphakheji ye-IP- -ukuguqulwa kwedatha
Isixhobo seVoIP ekusingise kuso sifumana le datha ye-IP kwaye siqalise ukuqhubekeka.Umphakamo wothungelwano ubonelela ngobude obuguquguqukayo besithinteli esisetyenziselwa ukulawula ijita eyenziwe yinethiwekhi.Isithinteli sinokwamkela iipakethi ezininzi zelizwi, kwaye abasebenzisi banokukhetha ubungakanani bebuffer.Izithinteli ezincinci zivelisa ukulibaziseka okuncinci, kodwa aziyilawuli ijitha enkulu.Okwesibini, idikhowuda ayicinezeli ipakethi yentetho ekhowudiweyo ukuze ivelise iphakheji entsha yentetho, kwaye le modyuli ingasebenza ngesakhelo, kanye ngobude obufanayo nedekhowuda.
Ukuba ubude befreyimu yi-15ms, iipakethe zelizwi le-60ms zohlulwa zibe ziifreyimu ezi-4, kwaye emva koko zikhowudilwe zibuyele kwi-60ms yedatha yelizwi kwaye ithunyelwe kwi-decoding buffer.Ngethuba lokucubungula ingxelo yedatha, ulwazi lwedilesi kunye nokulawula luyasuswa, idatha yoqobo yoqobo igcinwa, kwaye le datha yangaphambili inikezelwa kwi-decoder.
Intetho ye-5.Digital yaguqulelwa kwintetho ye-analog
Idrayivu yokudlala isusa iisampulu zelizwi (480) kwi-buffer kwaye izithumele kwikhadi lesandi ngesithethi ngamaza amiselweyo (umz. 8kHz).Ngamafutshane, ukuhanjiswa kweempawu zezwi kwinethiwekhi ye-IP kuhamba ngokuguqulwa ukusuka kwisignali ye-analog ukuya kwisignali yedijithali, ukupakishwa kwezwi ledijithali kwipakethi ye-IP, ukuhanjiswa kwepakethi ye-IP ngenethiwekhi, ukukhupha ipakethi ye-IP kunye nokubuyiselwa kwezwi ledijithali kwi-analog. uphawu.
Okwesibini, imigangatho yobugcisa enxulumene neVoIP
Ukusetyenziswa kwemultimedia kuthungelwano olukhoyo lonxibelelwano, i-International Telecommunication Union (ITU-T) iphuhlise i-H.32x ye-Multimedia series protocol protocol, le migangatho ilandelayo yenkcazo elula:
H.320, Umgangatho wonxibelelwano lwe-multimedia kwi-narrowband yevidiyo inkqubo yefowuni kunye ne-terminal (N-ISDN);
H.321, Umgangatho wonxibelelwano lwemultimedia kwi-B-ISDN;
H.322.Umgangatho wonxibelelwano lwemultimedia kwi-LAN eqinisekiswe yiQoS;
H.323.Umgangatho wonxibelelwano lwemultimedia kwinethiwekhi yokutshintsha ipakethi ngaphandle kwesiqinisekiso seQoS;
I-H.324, umgangatho wonxibelelwano lwe-multimedia kwii-terminals zonxibelelwano lwe-bit ephantsi (PSTN kunye nenethiwekhi engenazintambo).
Phakathi kwezi migangatho zingentla, H. I-323 i-Standard-defined networks isetyenziswa kakhulu, njenge-Ethernet, i-Token Network, i-FDDI Network, njl. ngenxa ye-H.Ukusetyenziswa kwe-323 esemgangathweni kuye ngokwemvelo ibe yindawo eshushu kwimarike, ngoko ngezantsi siza kugxila kwi-H.323.H.323 Amacandelo amane aphambili achazwe kwisindululo: i-terminal, isango, i-software yokulawula isango (eyaziwa ngokuba yisango okanye isango), kunye neyunithi yokulawula amanqaku amaninzi.
1.Itheminali (Itheminali)
Zonke iitheminali kufuneka zixhase unxibelelwano lwelizwi, kunye nevidiyo kunye nedatha yonxibelelwano nekhono lokuzikhethela.yonke i-H.Itheminali ye-323 kufuneka kwakhona ixhase i-H.245 Standard, H.245 Umgangatho usetyenziselwa ukulawula ukusetyenziswa kwetshaneli kunye nokusebenza kwetshaneli.H .323 Iiparameters eziphambili zekhowudi yentetho kunxibelelwano lwezwi zichazwe ngolu hlobo lulandelayo: ITU ecetyiswayo yebhanwidth yelizwi / KHz transmission bit rate / Kb/s compression algorithm annotation G.711 3.4 56,64 PCM elula yokucinezela, esetyenziswa kwi-PSTN kwi-G .728 3.4 16 Umgangatho wezwi we-LD-CELP njenge-G.711, njengoko usetyenziswa kumlinganiselo ophantsi-bit-rate wothumelo G.722 7 48,56,64 ADPCM umgangatho welizwi uphezulu kune-G.711, isetyenziswe kumlinganiselo ophezulu wokuhambisa i-G. . G.723.1.
2.Isango (Isango)
Le yi-H.Inketho yenkqubo ye-323. Isango liyakwazi ukuguqula iiprothokholi, i-audio, i-algorithms yekhowudi yevidiyo kunye neempawu zokulawula ezisetyenziswa kwiinkqubo ezahlukeneyo ukulungiselela unxibelelwano lwe-terminal yenkqubo.Njenge-PSTN-based ye-H.324 System kunye ne-narrowband. I-ISDN-based H.The 320 System kunye ne-H.323 Ukunxibelelana kwenkqubo, kuyimfuneko ukuqwalasela isango;
3.Ukugcina izithethe (Umgcini-sango)
Eli licandelo le-H.Icandelo elikhethiweyo lenkqubo ye-323 yi-software yokugqiba umsebenzi wokulawula.Inemisebenzi emibini ephambili: eyokuqala kulawulo lweSicelo se-H.323;okwesibini kulawulo lonxibelelwano lwe-terminal ngesango (njengokusekwa kwefowuni, ukususwa, njl. njl.) Abaphathi banokwenza ukuguqulwa kwedilesi, ukulawulwa kwe-bandwidth, ukuqinisekiswa kwefowuni, ukurekhodwa kwefowuni, ukubhaliswa komsebenzisi, ulawulo lwesizinda sonxibelelwano kunye neminye imisebenzi ngokusebenzisa amasiko. ukugcina.enye H.323 Indawo yonxibelelwano ingaba namasango amaninzi, kodwa isango elinye kuphela elisebenzayo.
4.Iyunithi yolawulo lwamanqaku amaninzi (iYunithi yoLawulo lwamanqaku amaninzi)
I-MCU yenza unxibelelwano lwamanqaku amaninzi kwinethiwekhi ye-IP, kwaye unxibelelwano lwe-point-to-point alufunwa.Inkqubo yonke yenza i-topology yenkwenkwezi nge-MCU.I-MCU iqulethe izinto ezimbini eziphambili: umlawuli we-multipoint MC kunye ne-multipoint processor MP, okanye ngaphandle kwe-MP.H phakathi kwee-terminal zokusetyenzwa kwe-MC.245 Ulwazi lokulawula ukwakha igama elincinane likawonke-wonke ukwenzela ukusetyenzwa kwe-audio kunye nevidiyo.MC ayiqhubeki ngokuthe ngqo nayiphi na imidiya yolwazi, kodwa iyishiya kwiMP. , ividiyo, okanye ulwazi lwedatha.
Kwishishini kukho izakhiwo ezimbini ezihambelanayo, enye yi-ITU-T H esungulwe ngasentla.323 Protocol yi-SIP protocol (RFC2543) ecetywayo yi-Internet Engineering Task Force (IETF), kwaye i-SIP protocol ifaneleke ngakumbi kwii-terminals ezihlakaniphile.
Okwesithathu, Impembelelo yophuhliso lweVoIP
Ukusetyenziswa ngokubanzi kweVoIP kuya kuzaliseka ngokukhawuleza ngenxa ye-hardware eninzi, isofthiwe, uphuhliso oluhambelanayo kunye nokuphumelela kwezobuchwepheshe kwiprotocol kunye nemigangatho.Inkqubela phambili yezobuchwepheshe kunye nophuhliso kule mimandla idlala indima yokuqhubela phambili ekudaleni inethiwekhi yeVoIP esebenza ngakumbi, esebenzayo kunye nesebenzisanayo. Imiba yobugcisa ekhuthaza uphuhliso olukhawulezayo kunye nosetyenziso olunabileyo lweVoIP lungashwankathelwa kwezi nkalo zilandelayo.
1.Digital Signal Processor
Iiprosesa zeempawu zedijithali ezikwizinga eliphezulu (Iprosesa yeDijithali yoMqondiso, iDSP) yenza amacandelo anzima okubalwa afunekayo ukuze izwi kunye nohlanganiso lwedatha.I-DSP iqhuba imiqondiso yedijithali ikakhulu ukwenza izibalo ezintsokothileyo ezinokuthi ngenye indlela zenziwe yi-CPU yendalo iphela. amandla okusebenza ngexabiso eliphantsi lenza i-DSP ifaneleke kakuhle ukwenza imisebenzi yokwenziwa komqondiso kwinkqubo yeVoIP.
Umjelo wezwi elinye kwi-G.729 Ixabiso le-computing yoxinzelelo lwezwi lidla ngokuba likhulu, lifuna i-20MIPS.Ukuba i-CPU esembindini iyafuneka ukwenza umzila kunye nolawulo lwenkqubo imisebenzi ngelixa kusetyenzwa imijelo yelizwi emininzi, oku akukho ngqiqweni.Ngoko ke, ukusebenzisa i-DSP enye okanye ngaphezulu kunokukhipha umsebenzi wekhompyutheni ye-algorithm yoxinzelelo lwezwi olunzima ukusuka kwi-CPU ephakathi.Ukongezelela, i-DSP ifanelekile ukufumanisa umsebenzi wezwi kunye nokucinywa kwe-echo, okubavumela ukuba baqhubele phambili imijelo yedatha yezwi ngexesha langempela kwaye bafikelele ngokukhawuleza. kwimemori yebhodi, ke.Kweli candelo, sichaza indlela yokuphumeza ikhowudi yelizwi kunye nokucinywa kwe-echo kwiqonga le-TMS320C6201DSP.
Iprotokholi kunye nesoftware esemgangathweni kunye nehardware H.323 Ilinganiswe ngendlela efanelekileyo yokufola iDSP MPLS ithegi yotshintshiselwano ilinganiswe ngokungalindelekanga ukubhaqwa kwangaphambili kwe-ASIC RTP, i-RTCP ifunnel ephindwe kabini ifaneli yomgangatho weseli jikelele algorithm DWDM RSVP ukale ukufikelela ngokukhawuleza izinga SONET Diffserv, CAR Cisco ugqithiso olukhawulezayo CPU processing amandla G. 729, G.729a: I-CS-ACELP iTheyibhile yoFikelelo oloNgezelelweyo ye-ADSL, iRADSL, i-SDSL FRF.11/FRF.12 i-algorithm ye-Token barrel algorithm ye-Multilink PPP Isakhelo soRelay Data ye-SIP esekelwe ekudityanisweni okuphambili kwe-CoS Packet phezu kwe-SONET IP kunye ne-ATM QoS / CoS
2.Iisekethe ezidityanisiweyo ezizinikezeleyo eziphambili
Uphuhliso lwe-Application-Specific Integrated Circait (ASIC) luvelise i-ASIC.ASIC ekhawulezayo, eyinkimbinkimbi, kwaye isebenze ngakumbi i-chip yesicelo esikhethekileyo esenza isicelo esisodwa okanye isethi encinci yemisebenzi.Ngenxa yokuba bagxininisa kwiinjongo zesicelo ezincinci kakhulu, zinokwandiswa kakhulu kwimisebenzi ethile, ngesiqhelo nge-CPU eneenjongo ezimbini enye okanye iiodolo ezininzi zobukhulu ngokukhawuleza.
Kanye njengokuba i-Thin Instruction iseti i-Computer (RSIC) chip igxile ekuqhutyweni ngokukhawuleza kwamanani alinganiselweyo, i-ASIC icwangciswe kwangaphambili ukuba yenze inani eliqingqiweyo lemisebenzi ngokukhawuleza.Xa uphuhliso lugqityiwe, iindleko ze-ASIC zemveliso ziphantsi, kwaye zisetyenziswa. kwizixhobo zenethiwekhi ezibandakanya ii-routers kunye nokutshintsha, ukwenza imisebenzi efana nokujonga itafile yomzila, ukuhanjiswa kweqela, ukuhlenga iqela kunye nokukhangela, kunye nokufola.Ukusetyenziswa kwe-ASIC kunika isixhobo ukusebenza okuphezulu kunye neendleko ezincinci.Babonelela nge-broadband eyandisiweyo kunye nenkxaso engcono ye-QoS womnatha, ngoko badlala indima enkulu ekukhuthazeni uphuhliso VoIP.
3.IP iteknoloji yokudlulisa
Uninzi lweenethiwekhi zosasazo lwe-telecom zisebenzisa ulwahlulo lwexesha lokuphindaphinda, ngelixa i-Intanethi kufuneka yamkele ukusetyenziswa kwakhona kwamanani kunye notshintshiselwano olude lwepakethi.Xa kuthelekiswa, le yokugqibela inezinga eliphezulu lokusetyenziswa kwemithombo yenethiwekhi, uqhagamshelwano olulula kunye olusebenzayo, kwaye lusebenza kakhulu kwiinkonzo zedatha, enye yezizathu ezibalulekileyo zokuphuhliswa ngokukhawuleza kwe-Intanethi.Nangona kunjalo, unxibelelwano lwenethiwekhi ye-broadband ye-IP ifuna i-QoS kunye neempawu zokulibaziseka. , ngoko uphuhliso lweenkcukacha-manani zokutshintshiselana ngepakethe yokuphindaphinda luye lwatsala umdla.Okwangoku, ukongeza kwisizukulwana esitsha se-IP protocol-IPV6, iqela lehlabathi lobunjineli be-Intanethi ye-Intanethi (IETF) licebise ngetekhnoloji yotshintshiselwano yethegi ye-multi-protocol (MPLS), le luhlobo lokukhetha umaleko wothungelwano olusekelwe kwiithegi ezahlukeneyo / utshintshiselwano lwelebhile, lunokuphucula ukuguquguquka kokhetho lwendlela, ukwandisa isakhono sokukhetha umaleko womnatha, lula umzila kunye nokudibanisa utshintshiselwano lwejelo, ukuphucula ukusebenza kwenethiwekhi.MPLS inokusebenza njengeprothokholi yomzila ozimeleyo, kwaye iyahambelana neprotocol yomzila wothungelwano ekhoyo, inkxaso yokusebenza eyahlukeneyo, ulawulo kunye nokugcinwa kwemisebenzi ye-IP network, yenza i-QoS, i-routing, i-signing performance iphuculwe kakhulu, ukufikelela okanye kufuphi nenqanaba lokusetyenziswa kwakhona kwe-statistical length fixed packet exchange (ATM), kwaye ilula, isebenzayo, iphantsi kwaye iyasebenza kune-ATM.
I-IETF ikwabambela ekuhlaleni iteknoloji entsha yeqela, ukuze kuphunyezwe ukhetho lwendlela yeQoS. “Itekhnoloji yetonela” iyaphononongwa ukuze kuphunyezwe ukuhanjiswa kwebroadband yendlela enye. Ukongeza, indlela yokukhetha iqonga lothumelo lwenethiwekhi ye-IP nayo intsimi ebalulekileyo yophando kwiminyaka yamuva, kunye ne-IP phezu kwe-ATM, i-IP phezu kwe-SDH, i-IP phezu kwe-DWDM kunye nobunye ubuchwepheshe buvele ngokulandelelana.
Uluhlu lwe-IP lubonelela abasebenzisi be-IP ngeenkonzo zokufikelela kwi-IP ezikumgangatho ophezulu kunye neziqinisekiso zenkonzo ethile.Uluhlu lomsebenzisi lubonelela ngefom yokufikelela (ukufikelela kwe-IP kunye nokufikelela kwi-broadband) kunye nefom yomxholo wenkonzo.Kwisiseko esisisiseko, i-Ethernet, njengomgangatho womzimba inethiwekhi ye-IP, yinto ekhoyo, kodwa i-IP overDWDM inobuchwepheshe bamva nje, kwaye inamandla amakhulu ophuhliso.
I-Dense Wave Division MultipLexing (DWDM) ifaka ubomi obutsha kuthungelwano lwefayibha kwaye inikezela nge-bandwidth emangalisayo kwiinkampani ze-telecom ezibeka i-fiber backbone entsha.I-teknoloji ye-DWDM isebenzisa izakhono ze-optical fibers kunye nezixhobo zokuhambisa umbane ophezulu. i-wavelengths yokukhanya (i-LASER) ukusuka kumlambo omnye we-fiber optical.Iinkqubo zangoku zingathumela kwaye ziqaphele i-16 wavelengths, ngelixa iinkqubo zexesha elizayo zingaxhasa i-40 ukuya kwi-96 i-wavelengths epheleleyo.Oku kubalulekile kuba i-wavelength nganye eyongezelelweyo yongeza ukuhamba okongezelelweyo kolwazi.Unako ngoko ke ukwandisa inethiwekhi ye-2.6 Gbit / s (OC-48) ngamaxesha e-16 ngaphandle kokubeka iifayili ezintsha.
Uninzi lwamanethiwekhi amatsha amatsha aqhuba i-OC-192 kwi-(9.6 Gbit / s), amandla okuvelisa ngaphezu kwe-150 Gbit / s kwi-pair of fibers xa zidibaniswe ne-DWDM.Ukongezelela, i-DWDM ibonelela ngeprotocol ye-interface kunye neempawu ezizimeleyo ezikhawulezayo, kwaye ixhasa zombini i-ATM. , I-SDH kunye ne-Gigabit Ethernet ukuhanjiswa kwesignali kwi-fiber enye, enokuthi ihambelane nothungelwano olukhoyo, ngoko i-DWDM inokukhusela iimpahla ezikhoyo, kodwa ibonelele i-ISP kunye neenkampani ze-telecom ezinomqolo onamandla, kwaye zenze i-broadband ingabizi kwaye ifikeleleke ngakumbi, ebonelela. inkxaso eyomeleleyo kwiimfuno zebhanwidth yezisombululo zeVoIP.
Isantya sothumelo esongeziweyo asikwazi nje ukubonelela ngombhobho orhabaxa onethuba elincinane lokuthintela, kodwa nokunciphisa ukulibaziseka ngobuninzi, kwaye ngoko kunokunciphisa kakhulu iimfuno ze-QoS kwiinethiwekhi ze-IP.
4.Iteknoloji yokufikelela kwiBroadband
Ukufikelela komsebenzisi kwinethiwekhi ye-IP kuye kwaba ngumqobo othintela ukuphuhliswa kwenethiwekhi yonke.K kunye nenethiwekhi ye-passive optical.Iyangaphambili ininzi e-United States, idibene nomlomo ovulekileyo we-V5.1 / V5.2, ihambisa inkqubo yayo edibeneyo kwi-fiber optical, ebonisa amandla amakhulu.
Le yokugqibela ikakhulu ngomyalelo kunye eJamani.Ngaphezu kweminyaka elishumi, Japan uye wathatha uluhlu lwamanyathelo ukunciphisa iindleko womnatha optical passiv ukuya kwinqanaba elifana neentambo zobhedu kunye nentsimbi ephothiweyo iperi, kwaye wayisebenzisa use.Ingakumbi. Kwiminyaka yakutshanje, i-ITU iphakamise i-ATM-based passive optical network (APON), encedisana ne-ATM kunye ne-passive optical network.Izinga lokufikelela linokufikelela kwi-622 M bit / s, enenzuzo kakhulu ekuphuhlisweni kwenkonzo ye-multimedia ye-IP ye-broadband, kwaye inokunciphisa izinga lokungaphumeleli kunye nenani leendawo, kunye nokwandisa ukugubungela.Okwangoku, i-ITU igqibe umsebenzi wokulinganisa. , abavelisi baphuhlisa ngenkuthalo, kuya kubakho iimpahla kwimarike, iya kuba yikhokelo yophuhliso oluphambili lweteknoloji yokufikelela kwi-broadband kwinkulungwane yama-21.
Okwangoku, ubugcisa obuphambili bokufikelela bubu: PSTN, IADN, ADSL, CM, DDN, X.25 kunye ne-Ethernet kunye nekholamu yenkqubo yokufikelela kwi-wireless ye-broadband, njl.Obu buchwephesha bokufikelela buneempawu zabo, kubandakanywa ne-ADSL ekhula ngokukhawuleza kunye ne-CM;I-CM (iModem yeCable) isebenzisa intambo ye-coaxial, izinga eliphezulu lokudluliselwa, amandla anamandla okuchasana nokuphazamiseka;kodwa hayi indlela ezimbini zothumelo, akukho mgangatho ufanayo.I-ADSL (i-Asymmetrical Digital Loop) inokufikelela kuphela kwi-broadband, isebenzisa ngokupheleleyo inethiwekhi yefowuni ekhoyo kunye nokubonelela ngezinga lokudluliselwa kwe-asymmetric.Izinga lokukhuphela kwicala lomsebenzisi linokufikelela kwi-8 Mbit / s, kwaye izinga lokulayisha kwicala lomsebenzisi linokufikelela kwi-1M bit / s.ADSL inikezela nge-broadband efunekayo kumashishini kunye nabo bonke abasebenzisi, kwaye iyanciphisa kakhulu iindleko.Ukusebenzisa i-ADSL yexabiso eliphantsi. iisekethe zengingqi, iinkampani ngoku zifikelela kwi-Intanethi kunye ne-Intanethi esekwe kwi-VPN ngesantya esiphezulu, evumela umthamo ophezulu wokufowuna weVoIP.
5.Ubuchwephesha beyunithi yokucubungula ephakathi
Iiyunithi zokucwangcisa ezisembindini (CPU) ziyaqhubeka nokuvela kumsebenzi, amandla, kunye nesantya.Oku kuvumela ukusetyenziswa ngokubanzi kwe-PC yemultimedia kunye nokuphucula ukusebenza kwemisebenzi yenkqubo ekhawulelwe yi-CPU amandla.Ikhono lePC lokucwangcisa idatha yomsindo kunye nevidiyo kudala ilindelwe. ngabasebenzisi, ngoko ukuhambisa iifowuni zelizwi kuthungelwano lwedatha ngokwemvelo yinjongo elandelayo.Olu phawu lwekhompuyutha luvumela zombini usetyenziso oluphezulu lwe-desktop yemultimedia kunye neempawu eziphambili kumacandelo enethiwekhi ukuxhasa izicelo zelizwi.