Cov xov tooj qub network yog lub suab los ntawm kev sib pauv hauv Circuit Court, qhov yuav tsum tau muaj kev sib kis broadband ntawm 64kbit / s. Lub npe hu ua VoIP yog IP pob ntawv sib pauv network raws li lub platform kis tau tus mob, simulated lub suab teeb liab compression, ntim thiab ua haujlwm tshwj xeeb, kom nws tuaj yeem siv tsis txuas UDP raws tu qauv rau kev sib kis.
Ntau lub ntsiab lus thiab kev ua haujlwm yuav tsum tau xa cov suab paj nruag ntawm IP network. Daim ntawv yooj yim tshaj plaws ntawm lub network muaj ob lossis ntau yam khoom siv nrog VoIP peev xwm uas txuas nrog ntawm IP network.
1.Voice-Data Transformation
Lub suab teeb liab yog analog waveform, los ntawm IP los xa lub suab, txawm tias lub sijhawm ua lag luam lossis kev lag luam hauv lub sijhawm tiag tiag, ua ntej rau lub suab teeb liab analog cov ntaub ntawv hloov dua siab tshiab, uas yog lub suab analog teeb liab 8 lossis 6 kom muaj nuj nqis, thiab tom qab ntawd xa mus rau qhov chaw cia khoom. , qhov loj ntawm qhov tsis tuaj yeem xaiv raws li qhov xav tau ntawm kev ncua sijhawm thiab coding. Ntau tus lej qis qis qis yog encoded hauv thav ntawv.
Qhov ntev ntawm tus ncej yog li ntawm 10 mus rau 30 ms. Xav txog cov nqi thaum sib kis, cov pob ntawv sib txuas feem ntau muaj 60, 120, lossis 240ms ntawm cov ntaub ntawv hais lus. Digitization tuaj yeem siv tau siv ntau lub suab coding schemes, thiab tam sim no lub suab coding qauv feem ntau yog ITU-T G.711. Lub suab encoder ntawm qhov chaw lo lus uas peb yuav tsum siv tib lub algorithm kom lub suab hais lus ntawm qhov chaw tuaj yeem rov qab tau cov teeb liab hais lus analog.
2.Original data-rau-IP conversion
Thaum lub teeb liab hais lus yog digitally coded, cov kauj ruam tom ntej yog compress encode lub pob ntawv hais lus nrog ib lub sijhawm ntev. Feem ntau ntawm cov encoders muaj ib tug tshwj xeeb ncej ntev. Yog tias tus encoder siv 15ms thav ntawv, 60ms pob los ntawm thawj qhov chaw muab faib ua plaub thav ntawv thiab encoded ua ntu zus. Txhua tus ncej muaj 120 tus qauv hais lus (sampling tus nqi ntawm 8kHz). Tom qab encoding, plaub compressed thav duab tau muab tso rau hauv ib lub pob hais lus compressed thiab xa mus rau lub network processor. Lub network processor ntxiv Baotou, lub sijhawm teev, thiab lwm yam ntaub ntawv rau lub suab thiab kis mus rau lwm qhov kawg ntawm lub network.
Lub network hais lus tsuas yog tsim kom muaj kev sib txuas ntawm lub cev ntawm qhov kawg ntawm kev sib txuas lus (ib kab) thiab xa cov teeb liab encoded ntawm qhov kawg. Tsis zoo li kev sib txuas hauv Circuit Court, IP tes hauj lwm tsis tsim kev sib txuas. Nws yuav tsum tau muab cov ntaub ntawv muab tso rau hauv cov ntaub ntawv sib txawv ntev los yog pob ntawv, tom qab ntawd chaw nyob thiab tswj cov ntaub ntawv rau txhua tus datagram thiab xa mus rau lub network, xa mus rau qhov chaw.
3. Hloov
Nyob rau hauv cov channel no, tag nrho lub network tau saib raws li lub suab pob ntawv tau txais los ntawm cov tswv yim thiab tom qab ntawd xa mus rau lub network tso tawm hauv ib lub sijhawm (t). Lub t tuaj yeem sib txawv hauv ntau yam, qhia txog qhov jitters hauv kev sib kis hauv lub network.
Tib lub node hauv network xyuas cov ntaub ntawv chaw nyob uas cuam tshuam nrog txhua tus IP cov ntaub ntawv thiab siv cov ntaub ntawv no los xa cov datagram mus rau qhov chaw nres tsheb tom ntej ntawm txoj hauv kev. Ib qho kev sib txuas hauv lub network tuaj yeem yog ib qho topology lossis kev nkag mus uas txhawb nqa IP cov ntaub ntawv ntws.
4.The IP pob- -kev hloov pauv ntawm cov ntaub ntawv
Lub hom phiaj VoIP ntaus ntawv tau txais cov ntaub ntawv IP no thiab pib ua haujlwm. Lub network theem muab qhov sib txawv ntawm qhov ntev tsis siv los tswj cov jitter tsim los ntawm lub network. Lub tsis tuaj yeem ua raws li ntau lub suab ntim, thiab cov neeg siv tuaj yeem xaiv qhov loj ntawm qhov tsis. Cov buffers me me tsim cov latency tsawg, tab sis tsis tswj cov jitters loj. Qhov thib ob, tus decoder uncompresses lub encoded hais lus pob ntawv los tsim ib tug tshiab hais lus pob, thiab cov module no kuj muaj peev xwm ua hauj lwm los ntawm thav duab, raws nraim tib ntev li lub decoder.
Yog hais tias tus ncej ntev yog 15ms, 60ms lub suab ntim tau muab faib ua 4 thav ntawv, thiab tom qab ntawd lawv tau txiav txim siab rov qab mus rau 60ms lub suab cov ntaub ntawv ntws thiab xa mus rau qhov kev txiav txim siab tsis. Thaum lub sijhawm ua cov ntaub ntawv tshaj tawm, qhov chaw nyob thiab tswj cov ntaub ntawv raug tshem tawm, cov ntaub ntawv qub qub raug khaws cia, thiab cov ntaub ntawv qub no yog muab rau tus decoder.
5.Digital hais lus tau hloov mus rau kev hais lus analog
Lub playback tsav tshem tawm cov qauv suab (480) hauv qhov tsis thiab xa lawv mus rau daim npav suab los ntawm tus neeg hais lus ntawm qhov zaus tau txiav txim siab (xws li 8kHz). Nyob rau hauv luv luv, kev sib kis ntawm lub suab teeb liab ntawm tus IP network mus los ntawm kev hloov dua siab tshiab los ntawm analog teeb liab mus rau cov teeb liab digital, digital suab ntim rau hauv ib pob ntawv IP, IP pob ntawv kis tau tus mob los ntawm lub network, IP pob ntawv unpacking thiab kho dua lub suab digital mus rau analog. teeb liab.
Thib ob, VoIP-txog cov qauv kev qhia
Rau cov ntawv thov multimedia ntawm kev sib txuas lus uas twb muaj lawm, International Telecommunication Union (ITU-T) tau tsim H.32x Multimedia kev sib txuas lus series raws tu qauv, cov qauv hauv qab no rau cov lus piav qhia yooj yim:
H.320, Txuj rau kev sib txuas lus multimedia ntawm lub kaw lus kaw lus video thiab lub davhlau ya nyob twg (N-ISDN);
H.321, Txuj rau kev sib txuas lus multimedia ntawm B-ISDN;
H.322. Txuj kev sib txuas lus multimedia ntawm LAN tau lees paub los ntawm QoS;
H.323. Tus qauv rau kev sib txuas lus multimedia ntawm pob ntawv hloov pauv tsis muaj QoS lav;
H.324, tus qauv rau kev sib txuas lus multimedia ntawm cov chaw sib txuas lus qis qis (PSTN thiab wireless network).
Ntawm cov qauv saum toj no, H. Cov 323 Standard-txhais tes hauj lwm yog cov siv dav tshaj plaws, xws li Ethernet, Token Network, FDDI Network, thiab lwm yam.vim H.Qhov kev thov ntawm 323 tus qauv tau dhau los ua qhov chaw kub hauv khw, yog li hauv qab no peb yuav tsom mus rau H.323.H.323 Plaub lub ntsiab lus tau hais tseg hauv daim ntawv thov: davhlau ya nyob twg, rooj vag, rooj vag tswj software (tseem hu ua rooj vag lossis rooj vag), thiab chav tswj ntau qhov chaw.
1. Terminal (Terminal)
Txhua lub davhlau ya nyob twg yuav tsum txhawb lub suab sib txuas lus, thiab lub peev xwm video thiab cov ntaub ntawv sib txuas lus yog xaiv tau.Txhua H.The 323 lub davhlau ya nyob twg yuav tsum txhawb nqa H.245 Standard, H.245 tus qauv siv los tswj kev siv channel thiab kev ua haujlwm ntawm channel.H .323 Qhov tseem ceeb ntawm kev hais lus codec hauv lub suab sib txuas lus tau teev tseg raws li nram no: ITU pom zoo lub suab bandwidth / KHz kis me ntsis tus nqi / Kb / s compression algorithm annotation G.711 3.4 56,64 PCM yooj yim compression, thov rau PSTN hauv G .728 3.4 16 LD-CELP lub suab zoo li G.711, raws li siv rau qhov qis-ntsis-tus kis tau tus mob G.722 7 48,56,64 ADPCM lub suab zoo yog siab dua G.711, siv rau kev sib kis tus nqi siab G. .723.1G.723.0 3.4 6.35.3 LP-MLQ Lub suab zoo tau txais, G.723.1 Txais ib G rau lub rooj sib tham VOIP.729G.729A 3.4 8 CS-ACELP ncua qis dua G.723.1, Lub suab zoo dua g 723.1.
2. Rooj vag (Gateway)
Qhov no yog H.An kev xaiv rau 323 system.Lub rooj vag muaj peev xwm hloov tau cov kev cai, suab, video coding algorithms thiab tswj cov cim siv los ntawm cov tshuab sib txawv kom haum rau qhov system davhlau ya nyob twg kev sib txuas lus.Xws li PSTN-raws li H.324 System thiab nqaim band. ISDN-raws li H.The 320 System thiab H.323 Rau kev sib txuas lus system, nws yog ib qho tsim nyog los teeb tsa lub rooj vag;
3. Kev lis kev cai (Gatekeeper)
Qhov no yog H.Ib qho kev xaiv ntawm 323 system yog software ua kom tiav cov kev tswj hwm kev ua haujlwm.Nws muaj ob lub luag haujlwm tseem ceeb: thawj zaug yog rau H.323 Daim Ntawv Thov Kev Tswj Xyuas; Qhov thib ob yog kev tswj hwm lub davhlau ya nyob twg kev sib txuas lus los ntawm lub rooj vag (xws li kev tsim kev hu xov tooj, tshem tawm, thiab lwm yam). Cov thawj coj tuaj yeem ua qhov chaw nyob hloov dua siab tshiab, tswj bandwidth, hu rau authentication, hu rau cov ntaub ntawv sau npe, cov neeg siv sau npe, kev sib txuas lus tswj hwm thiab lwm yam haujlwm los ntawm kev lis kev cai. keeping.one H.323 Lub chaw sib txuas lus tuaj yeem muaj ntau lub rooj vag, tab sis tsuas yog ib lub rooj vag ua haujlwm xwb.
4.Multipoint control unit (Multipoint Control Unit)
MCU tso cai rau kev sib txuas lus ntau ntawm IP network, thiab tsis tas yuav tsum muaj kev sib txuas lus taw tes rau-taw tes.Txhua lub kaw lus tsim lub hnub qub topology los ntawm MCU.Lub MCU muaj ob lub ntsiab lus tseem ceeb: multipoint controller MC thiab multipoint processor MP, lossis yam tsis muaj MP.H ntawm MC ua terminals.245 Tswj cov ntaub ntawv los tsim kom muaj lub npe me me rau kev ua suab thiab video.MC tsis ncaj qha cov ntaub ntawv xov xwm kwj, tab sis tawm mus rau MP.The MP sib tov, hloov, thiab ua cov suab. , video, lossis cov ntaub ntawv xov xwm.
Hauv kev lag luam muaj ob qhov kev sib txuas ua ke, ib qho yog ITU-T H qhia saum toj no.323 raws tu qauv yog SIP raws tu qauv (RFC2543) tau npaj los ntawm Internet Engineering Task Force (IETF), thiab SIP raws tu qauv yog tsim nyog rau cov ntse terminals.
Thib peb, Lub zog rau kev txhim kho VoIP
Kev siv VoIP thoob plaws yuav tshwm sim sai sai vim muaj ntau yam khoom kho vajtse, software, cuam tshuam txog kev txhim kho thiab kev siv thev naus laus zis hauv cov txheej txheem thiab cov qauv. Cov yam ntxwv tseem ceeb uas txhawb txoj kev loj hlob sai thiab txawm tias siv dav dav ntawm VoIP tuaj yeem raug sau tseg rau hauv cov hauv qab no.
1.Digital Signal Processor
Advanced digital signal processors (Digital Signal Processor, DSP) ua cov khoom siv suav nrog cov khoom siv rau lub suab thiab cov ntaub ntawv sib xyaw.DSP ua cov cim digital feem ntau los ua cov kev suav nyuaj uas tej zaum yuav tsum tau ua los ntawm universal CPU.Cov kev sib txuas ntawm lawv qhov tshwj xeeb. ua lub zog nrog tus nqi qis ua rau DSP zoo haum rau kev ua cov teeb liab ua haujlwm hauv VoIP system.
Ib lub suab kwj ntawm G.729 Kev suav nqi ntawm lub suab compression feem ntau loj, xav tau 20MIPS. Yog hais tias lub hauv paus CPU yuav tsum tau ua routing thiab system tswj kev ua haujlwm thaum ua ntau lub suab ntws, qhov no tsis muaj tseeb. Yog li ntawd, siv ib lossis ntau dua DSP tuaj yeem tshem tawm cov haujlwm ua haujlwm ntawm lub suab nrov compression algorithm los ntawm lub hauv paus CPU. Tsis tas li ntawd, DSP yog qhov tsim nyog rau kev tshawb nrhiav lub suab thiab ncha tshem tawm, tso cai rau lawv ua cov ntaub ntawv suab hauv lub sijhawm thiab nkag mus sai. on-board nco, yog li.Nyob rau hauv seem no, peb nthuav dav yuav ua li cas siv lub suab coding thiab ncha tshem tawm ntawm TMS320C6201DSP platform.
Cov txheej txheem thiab cov txheej txheem software thiab kho vajtse H.323 Qhov hnyav ncaj ncees queuing txoj kev DSP MPLS tag pauv hnyav random thaum ntxov tshawb pom siab heev ASIC RTP, RTCP dual funnel general cell rate algorithm DWDM RSVP rated nkag ceev tus nqi SONET Diffserv, CAR Cisco ceev forwarding CPU ua fais fab G. 729, G.729a: CS-ACELP Extended Access Table ADSL, RADSL, SDSL FRF.11/FRF.12 Token chim algorithm Multilink PPP Ncej Relay Cov Ntaub Ntawv Rectifier SIP raws li qhov tseem ceeb ntawm kev koom ua ke ntawm CoS Pob ntawv hla SONET IP thiab ATM QoS / CoS
2.Advanced integrated circuits
Daim ntawv thov-Specific Integrated Circait (ASIC) txoj kev loj hlob tau ua kom sai dua, nyuaj, thiab ua haujlwm tau zoo dua ASIC.ASIC yog ib daim ntawv thov tshwj xeeb nti uas ua tau ib daim ntawv thov lossis ib pawg me me ntawm kev ua haujlwm.Vim lawv tsom rau cov hom phiaj ntawm daim ntawv thov nqaim heev, lawv tuaj yeem ua tau zoo heev rau cov haujlwm tshwj xeeb, feem ntau yog siv ob lub hom phiaj CPU ib lossis ntau qhov kev txiav txim ntawm qhov loj dua.
Ib yam li Thin Instruction set Computer (RSIC) nti tsom rau kev ua kom ceev ntawm cov lej txwv, ASIC tau npaj ua ntej kom ua tiav cov haujlwm nrawm dua.Thaum kev txhim kho tiav, tus nqi ntawm ASIC pawg ntau lawm yog tsawg, thiab nws yog siv. rau cov khoom siv network suav nrogroutersthiab cov keyboards, ua haujlwm xws li routing table checking, pab pawg xa mus, pab pawg sorting thiab checking, thiab queuing.Qhov kev siv ASIC muab cov cuab yeej ua haujlwm tau zoo dua thiab tsis muaj nqi.Lawv muab ntau dua broadband thiab zoo dua QoS kev txhawb nqa rau lub network, yog li lawv ua si. lub luag haujlwm tseem ceeb hauv kev txhawb nqa kev txhim kho VoIP.
3.IP kis tau tus mob technology
Feem ntau cov kev sib txuas lus sib txuas lus siv sijhawm sib faib sib faib, thaum Is Taws Nem yuav tsum tau txais cov ntaub ntawv rov qab siv dua thiab kev sib pauv pob ntawv ntev. Piv txwv li, tom kawg muaj kev siv siab ntawm cov peev txheej hauv network, kev sib txuas yooj yim thiab siv tau zoo, thiab siv tau rau cov ntaub ntawv 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 xav tau QoS thiab ncua cov yam ntxwv. Tam sim no, ntxiv rau lub cim tshiab ntawm IP raws tu qauv-IPV6, lub ntiaj teb Internet engineering pab pawg (IETF) tau thov kom muaj ntau txoj kev sib pauv pauv tshuab (MPLS), qhov no. yog ib hom network txheej xaiv raws li ntau yam cim / daim ntawv sib pauv, tuaj yeem txhim kho qhov yooj yim ntawm txoj kev xaiv, nthuav dav network txheej xaiv muaj peev xwm, ua kom yooj yim raurouterthiab kev sib pauv kev sib koom ua ke, txhim kho network kev ua tau zoo.MPLS tuaj yeem ua haujlwm raws li kev ywj pheej routing raws tu qauv, thiab sib haum nrog lub network routing raws tu qauv, txhawb ntau yam kev ua haujlwm, kev tswj hwm thiab kev saib xyuas ntawm IP network, ua rau QoS, routing, signaling kev ua tau zoo heev, kom ncav cuag lossis ze rau qib ntawm cov ntaub ntawv txheeb xyuas rov qab siv lub sijhawm ntev pob ntawv pauv (ATM), thiab yooj yim, siv tau, pheej yig thiab siv tau dua li ATM.
IETF tseem nyob hauv cheeb tsam tuav cov pab pawg tshiab thev naus laus zis, txhawm rau ua tiav QoS txoj kev xaiv.The "tunnel thev naus laus zis" tab tom kawm kom ua tiav kev sib kis ntawm kev sib txuas ntawm ib txoj kev sib txuas. Kev tshawb fawb tseem ceeb hauv xyoo tas los no, thiab IP dhau ATM, IP dhau SDH, IP dhau DWDM thiab lwm yam thev naus laus zis tau tshwm sim ua tiav.
Cov txheej txheem IP muab cov neeg siv IP nrog cov kev pabcuam zoo IP nkag tau nrog qee qhov kev pabcuam lav.Cov neeg siv txheej muab daim ntawv nkag (IP nkag mus thiab kev siv dav dav) thiab cov ntsiab lus kev pabcuam.Nyob hauv txheej txheej, Ethernet, raws li txheej txheej ntawm lub cev. IP network, yog ib qho teeb meem, tab sis IP overDWDM muaj cov thev naus laus zis tshiab, thiab muaj peev xwm loj hlob.
Dense Wave Division MultipLexing (DWDM) txhaj lub neej tshiab rau hauv fiber ntau tes hauj lwm thiab muab amazing bandwidth nyob rau hauv telecom tuam txhab uas muag nteg tshiab fiber backbone.DWDM technology siv lub peev xwm ntawm optical fibers thiab advanced optical kis khoom siv.Lub npe ntawm yoj division multiplexing yog muab los rau kis ntau yam. wavelengths ntawm lub teeb (LASER) los ntawm ib qho kwj ntawm fiber ntau optical.Tam sim no cov tshuab tuaj yeem xa thiab paub txog 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 ntxiv.Koj tuaj yeem ua tau Yog li nthuav dav 2.6 Gbit / s (OC-48) network los ntawm 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 nrawm nrawm, thiab txhawb nqa ob lub ATM. , SDH thiab Gigabit Ethernet teeb liab kis tau tus mob ntawm ib qho fiber ntau, uas tuaj yeem sib haum nrog cov tes hauj lwm uas twb muaj lawm, yog li DWDM tuaj yeem tiv thaiv cov cuab tam uas twb muaj lawm, tab sis kuj muab cov tuam txhab ISP thiab cov tuam txhab xov tooj nrog cov pob txha muaj zog, thiab ua kom broadband tsis tshua muaj nqi thiab siv tau ntau dua, uas muab muaj zog txhawb rau cov kev cai bandwidth ntawm VoIP kev daws teeb meem.
Qhov kev sib kis tau nce ntxiv tuaj yeem tsis tsuas yog muab cov raj xa dej sib txuas nrog tsawg dua ntawm kev thaiv, tab sis kuj txo qhov ncua sij hawm ntau, thiab yog li tuaj yeem txo qis QoS cov cai ntawm IP tes hauj lwm.
4.Broadband nkag tshuab
Tus neeg siv kev nkag mus rau IP network tau dhau los ua ib qho kev txwv tsis pub muaj kev loj hlob ntawm tag nrho cov network.Nyob rau hauv lub sij hawm ntev, lub hom phiaj ntawm cov neeg siv kev nkag mus rau lub tsev yog fiber-to-home (FTTH). thiab passive optical network.Tus qub yog tsuas yog nyob rau hauv Teb Chaws Asmeskas, ua ke nrog qhib qhov ncauj V5.1/V5.2, kis nws cov kev sib xyaw ua ke ntawm optical fiber, uas qhia qhov tseem ceeb heev.
Lub tom kawg yog feem ntau nyob rau hauv kev txiav txim thiab nyob rau hauv lub teb chaws Yelemees.Rau ntau tshaj ib xyoo caum, Nyiv tau coj ib tug series ntawm kev ntsuas los txo tus nqi ntawm passive optical network mus rau ib theem zoo li tooj liab cables thiab hlau twisted khub, thiab siv nws siv.Tshwj xeeb tshaj yog Nyob rau hauv xyoo tas los no, ITU tau tshaj tawm ATM-based passive optical network (APON), uas ua kom tiav qhov zoo ntawm ATM thiab passive optical network. Tus nqi nkag tuaj yeem ncav cuag 622 M 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 cov kev pabcuam.Tam sim no, ITU tau ua tiav cov qauv kev ua haujlwm. , manufacturers yog nquag tsim, yuav muaj cov khoom nyob rau hauv kev ua lag luam, yuav dhau los ua lub ntsiab txoj kev loj hlob ntawm broadband access technology rau lub xyoo pua 21st.
Tam sim no, cov cuab yeej siv tseem ceeb yog: PSTN, IADN, ADSL, CM, DDN, X.25 thiab Ethernet thiab broadband wireless access system kem, thiab lwm yam.Cov cuab yeej siv no muaj lawv tus kheej cov yam ntxwv, suav nrog kev txhim kho sai tshaj plaws ADSL thiab CM; CM (Cable Modem) siv coaxial cable, siab kis tus nqi, muaj zog tiv thaiv kev cuam tshuam; tab sis tsis yog ob txoj kev sib kis, tsis muaj tus qauv zoo ib yam. ADSL (Asymmetrical Digital Loop) muaj kev nkag mus rau broadband nkaus xwb, 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 tuaj yeem ncav cuag 8 Mbit / s, thiab tus nqi upload ntawm tus neeg siv sab tuaj yeem ncav cuag 1M ntsis / s.ADSL muab qhov tsim nyog broadband rau cov lag luam thiab txhua tus neeg siv, thiab txo cov nqi zoo heev.Siv cov nqi qis dua ADSL. cov cheeb tsam hauv cheeb tsam, cov tuam txhab tam sim no nkag mus rau Is Taws Nem thiab Internet-based VPN ntawm qhov nrawm dua, tso cai rau VoIP hu ntau dua.
5.Central processing unit technology
Central processing units (CPU) txuas ntxiv txhim kho hauv kev ua haujlwm, lub zog, thiab kev nrawm.Qhov no ua rau muaj kev siv ntau ntawm PC multimedia thiab txhim kho kev ua haujlwm ntawm lub cev muaj zog txwv los ntawm CPU zog.Lub PC lub peev xwm los ua cov ntaub ntawv suab thiab video tau ntev tos. los ntawm cov neeg siv, yog li xa lub suab hu rau ntawm cov ntaub ntawv tes hauj lwm yog ib txwm lub hom phiaj tom ntej.Qhov kev suav no ua rau ob qho tib si cov ntawv thov multimedia desktop thiab cov yam ntxwv siab heev hauv cov khoom siv network los txhawb cov ntawv thov suab.