Naphezu kokusetshenziswa kabanzi kwamanethiwekhi e-Ethernet, ubuchwepheshe bokuxhumana obusekelwe ku-DSL buhlala bubalulekile nanamuhla. Kuze kube manje, i-DSL ingatholakala kumanethiwekhi okugcina amamayela okuxhuma imishini yokubhalisa kumanethiwekhi abahlinzeki be-inthanethi, futhi kamuva nje ubuchwepheshe busetshenziswa kakhulu ekwakhiweni kwamanethiwekhi endawo, ngokwesibonelo, kuzinhlelo zokusebenza zezimboni, lapho i-DSL isebenza njengokuhambisana ne-Ethernet. noma amanethiwekhi enkambu asekelwe ku-RS-232/422/485. Izixazululo ezifanayo zezimboni zisetshenziswa ngenkuthalo emazweni athuthukile aseYurophu nase-Asia.
I-DSL iwumndeni wezindinganiso ezakhelwa ukudlulisa idatha yedijithali ngezintambo zocingo. Ngokomlando, ibe ubuchwepheshe bokuqala bokufinyelela ku-inthanethi ye-broadband, ithatha indawo ye-DIAL UP ne-ISDN. Izinhlobonhlobo zezindinganiso ze-DSL ezikhona njengamanje kungenxa yokuthi izinkampani eziningi, kusukela ngeminyaka yawo-80s, zazama ukuthuthukisa nokuthengisa ubuchwepheshe bazo.
Konke lokhu kuthuthukiswa kungahlukaniswa ngezigaba ezimbili ezinkulu - ubuchwepheshe obungalingani (ADSL) kanye nobuchwepheshe be-symmetric (SDSL). I-asymmetric ibhekisela kulawo lapho isivinini soxhumano olungenayo sihluke kunesivinini sethrafikhi ephumayo. Nge-symmetric sisho ukuthi isivinini sokwamukela nokudlulisa siyalingana.
Amazinga asymmetric aziwa kakhulu futhi asabalele, empeleni, i-ADSL (enguqulweni yakamuva - ADSL2+) ne-VDSL (VDSL2), i-symmetric - HDSL (iphrofayili ephelelwe yisikhathi) kanye ne-SHDSL. Zonke ziyahlukahluka komunye nomunye ngokuthi zisebenza ngamaza ahlukene futhi zisebenzisa izindlela ezihlukene zokubhala amakhodi nokushintshashintsha emugqeni wokuxhumana ngokomzimba. Izindlela zokulungisa amaphutha nazo ziyahluka, okuholela emazingeni ahlukene okuvikela umsindo. Ngenxa yalokho, ubuchwepheshe obunye bunomkhawulo wabo ngesivinini kanye nebanga lokudluliswa kwedatha, kufaka phakathi kuye ngohlobo nekhwalithi yomqhubi.
Imikhawulo yamazinga ahlukahlukene e-DSL
Kunoma ibuphi ubuchwepheshe be-DSL, izinga lokudluliswa kwedatha liyehla njengoba ubude bekhebula bukhula. Ebangeni elibi kakhulu kungenzeka ukuthola isivinini samakhilobhithi angamakhulu amaningana, kodwa lapho udlulisela idatha ngaphezu kuka-200-300 m, isivinini esiphezulu esingenzeka siyatholakala.
Phakathi kwabo bonke ubuchwepheshe, i-SHDSL inenzuzo engathi sína eyenza kube nokwenzeka ukuyisebenzisa ezinhlelweni zezimboni - ukungavikeleki komsindo ophezulu kanye nekhono lokusebenzisa noma yiluphi uhlobo lomqhubi wokudlulisa idatha. Lokhu akunjalo ngezindinganiso ze-asymmetric, futhi ikhwalithi yokuxhumana incike kakhulu kukhwalithi yolayini osetshenziselwa ukudluliswa kwedatha. Ikakhulukazi, kunconywa ukusebenzisa ikhebula locingo elisontekile. Kulokhu, isisombululo esithembeke kakhulu ukusebenzisa ikhebula lokukhanya esikhundleni se-ADSL ne-VDSL.
Noma yimaphi ama-conductor ahlukanisiwe afanele i-SHDSL - ithusi, i-aluminium, insimbi, njll. I-transmission medium ingaba izintambo zikagesi ezindala, izintambo zocingo ezindala, ucingo oluhlabayo, njll.
Ukuncika kwesivinini sokudluliswa kwedatha ye-SHDSL ebangeni nakuhlobo lwekhondatha
Kusuka kugrafu yesivinini sokudluliswa kwedatha uma kuqhathaniswa nebanga kanye nohlobo lwekhondatha elinikezwe i-SHDSL, ungabona ukuthi amakhondatha anesiphambano esikhulu akuvumela ukuthi udlulise ulwazi ngebanga elikhulu. Ngenxa yobuchwepheshe, kungenzeka ukuhlela ukuxhumana ngebanga elingafika ku-20 km ngesivinini esiphezulu esingaba ngu-15.3 Mb/s ngekhebula lezintambo ezingu-2 noma i-30 Mb ngekhebula lezintambo ezingu-4. Kuzinhlelo zokusebenza zangempela, isivinini sokudlulisela singasethwa ngesandla, okudingekayo ezimeni zokuphazanyiswa okuqinile kozibuthe kagesi noma ikhwalithi yomugqa ongemuhle. Kulokhu, ukwandisa ibanga lokudlulisela, kuyadingeka ukunciphisa isivinini samadivayisi we-SHDSL. Ukubala ngokunembile isivinini kuye ngebanga kanye nohlobo lwekhondatha, ungasebenzisa isofthiwe yamahhala njenge .
Kungani i-SHDSL inokungavikeleki komsindo okuphezulu?
Isimiso sokusebenza se-transceiver ye-SHDSL singamelelwa ngendlela yomdwebo we-block, lapho ingxenye ethile nezimele (engaguquki) evela endaweni yokubuka yesicelo ihlukaniswa. Ingxenye ezimele iqukethe amabhlogo asebenzayo e-PMD (Physical Medium Dependent) kanye ne-PMS-TC (Physical Medium-Specific TC Layer), kuyilapho ingxenye ethile ihlanganisa ungqimba lwe-TPS-TC (Transmission Protocol-Specific TC Layer) kanye nezixhumi ezibonakalayo zedatha yomsebenzisi.
Isixhumanisi esibonakalayo phakathi kwama-transceivers (STUs) singaba khona njengepheya eyodwa noma izintambo ezingashadile eziningi. Endabeni yamapheya ekhebula amaningi, i-STU iqukethe ama-PMD amaningi azimele ahlotshaniswa ne-PMS-TC eyodwa.
Imodeli esebenzayo ye-SHDSL transceiver (STU)
Imojula ye-TPS-TC incike kuhlelo lokusebenza lapho idivayisi isetshenziswa khona (i-Ethernet, RS-232/422/485, njll.). Umsebenzi wayo ukuguqula idatha yomsebenzisi ibe ifomethi ye-SHDSL, ukwenza i-multiplexing/demultiplexing kanye nokulungiswa kwesikhathi kweziteshi ezimbalwa zedatha yomsebenzisi.
Ezingeni le-PMS-TC, amafreyimu e-SHDSL ayakhiwa futhi avumelaniswe, kanye nokuklwebha nokuhlehla.
Imojula ye-PMD yenza imisebenzi yokufaka ikhodi/ukukhipha amakhodi kolwazi, ukuguquguquka/ukwehlisa, ukukhansela i-echo, ukuxoxisana ngepharamitha emugqeni wokuxhumana nokusungula ukuxhumana phakathi kwama-transceivers. Kusezingeni le-PMD lapho imisebenzi eyinhloko yenziwa khona ukuze kuqinisekiswe ukungavikeleki komsindo okuphezulu kwe-SHDSL, okuhlanganisa ukufakwa kwekhodi kwe-TCPAM (i-Trellis coding ne-analog pulse modulation), indlela yokuhlanganisa yokuhlanganisa kanye nokushintshashintshashintshayo eyenza ngcono ukusebenza kahle kwesiginali uma kuqhathaniswa nesehlukile. indlela. Umgomo wokusebenza wemojula ye-PMD ungabuye umelwe ngendlela yomdwebo osebenzayo.
I-PMD Module Block Diagram
I-TC-PAM isuselwe ekusetshenzisweni kwesishumeki se-convolutional esikhiqiza ukulandelana okungadingekile kwamabhithi ohlangothini lwesidluliseli se-SHDSL. Emjikelezweni wewashi ngalinye, ibhithi ngalinye elifika kokokufaka kusishumeki linikezwa ibhithi eliphindwe kabili (i-dibit) ekukhishweni. Ngakho-ke, ngezindleko zokuphindaphinda okuncane, ukuvikeleka komsindo wokudlulisela kuyenyuka. Ukusetshenziswa kwe-Trellis modulation kukuvumela ukuthi wehlise umkhawulokudonsa wokudlulisa idatha osetshenzisiwe futhi wenze i-Hardware ibe lula ngenkathi ugcina isilinganiso esifanayo sesignali-to-noise.
Umgomo wokusebenza we-Trellis encoder (TC-PAM 16)
I-double bit yakhiwa ukusebenza okunengqondo kwe-modulo-2 (okukhethekile noma) okusekelwe kubhithi yokufaka ethi x1(tn) kanye nezingcezu x1(tn-1), x1(tn-2), njll. (kungaba nezingu-20 sezizonke), ezitholwe ngokokufaka kwesifaki khodi ngaphambilini futhi zahlala zigcinwe kumarejista ememori. Emjikelezweni wewashi olandelayo we-encoder tn+1, amabhithi azohanjiswa kumaseli enkumbulo ukuze enze umsebenzi onengqondo: i-bit x1(tn) izongena kumemori, iguqule lonke ukulandelana kwamabhithi agcinwe lapho.
I-algorithm ye-Convolutional yesifaki khodi
Amathebula eqiniso omsebenzi wokwengeza imodulo 2
Ukuze uthole ukucaca, kulula ukusebenzisa umdwebo wesimo wesishumeki se-convolutional, ongabona kuso ukuthi i-encoder ikusiphi isimo ngezinye izikhathi tn, tn+1, njll. kuye ngedatha yokufaka. Kulokhu, isimo sesishumeki sisho ipheya lamanani okokufaka kwebhithi x1(tn) kanye nebhithi kuseli yenkumbulo yokuqala x1(tn-1). Ukuze wakhe umdwebo, ungasebenzisa igrafu, kuma-vertices lapho kukhona izimo ezingaba khona zesifaki khodi, futhi ukuguquka ukusuka kwesinye isimo ukuya kwesinye kuboniswa amabhithi okufaka ahambisanayo x1(tn) kanye namabhithi okukhiphayo $inline$y ₀y ₁(t ₀)$inline$.
Umdwebo wesifunda kanye negrafu yoguquko yesishumeki se-transmitter convolutional
Ku-transmitter, ngokusekelwe kumabhithi amane atholiwe (izingcezu ezimbili zokukhiphayo ze-encoder nezingcezu ezimbili zedatha), kwakheka uphawu, ngalunye oluhambisana nobukhulu balo besignali yokumodulating ye-analog-pulse modulator.
Isimo se-16-bit AIM kuye ngevelu yohlamvu lwamabhithi amane
Ohlangothini lomamukeli wesignali, inqubo ehlehlayo iyenzeka - ukwehlisa nokukhethwa kukhodi engasasebenzi (amabhithi aphindwe kabili y0y1(tn)) wokulandelana okudingekayo kwamabhithi okokufaka kwesishumeki x1(tn). Lo msebenzi wenziwa i-Viterbi decoder.
I-algorithm yesikhiphi sisekelwe ekubaleni imethrikhi yephutha yazo zonke izifunda zesifaki khodi esilindelekile. Imethrikhi yephutha isho umehluko phakathi kwamabhithi atholiwe namabhithi alindelekile kundlela ngayinye engaba khona. Uma kungekho amaphutha okwamukela, khona-ke imethrikhi yephutha lendlela yeqiniso izoba ngu-0 ngenxa yokuthi akukho ukwehluka kancane. Ezindleleni zamanga, imethrikhi izohluka ku-zero, ikhule njalo, futhi ngemva kwesikhathi esithile isiqophi sizoyeka ukubala indlela eyiphutha, ishiye eyiqiniso kuphela.
Isifaki khodi somdwebo obalwa yisikhiphi se-Viterbi somamukeli
Kepha le algorithm iqinisekisa kanjani ukungavikeleki komsindo? Ngokucabangela ukuthi umamukeli uthole idatha ngephutha, idikhoda izoqhubeka nokubala izindlela ezimbili nge-metric yephutha engu-1. Indlela enemethrikhi yephutha engu-0 ngeke isaba khona. Kodwa i-algorithm izokwenza isiphetho mayelana nokuthi iyiphi indlela eyiqiniso kamuva ngokusekelwe kumabhithi aphindwe kabili atholakele.
Uma kwenzeka iphutha lesibili, kuzoba nemizila eminingi ene-metric 2, kodwa indlela elungile izokhonjwa ngokuhamba kwesikhathi ngokusekelwe endleleni enkulu yokungenzeka (okungukuthi, imethrikhi encane).
Umdwebo wesimo se-Encoder obalwa nge-Viterbi decoder lapho uthola idatha enamaphutha
Esimeni esichazwe ngenhla, njengesibonelo, sicabangele i-algorithm yesistimu ye-16-bit (TC-PAM16), eqinisekisa ukudluliswa kwezingcezu ezintathu zolwazi oluwusizo kanye nebhithi eyengeziwe yokuvikela iphutha kuphawu olulodwa. I-TC-PAM16 ifinyelela amanani edatha ukusuka ku-192 kuya ku-3840 kbps. Ngokwandisa ukujula kancane kuye ku-128 (amasistimu esimanje asebenza nge-TC-PAM128), amabhithi ayisithupha olwazi oluwusizo adluliselwa kuphawu ngalunye, futhi isivinini esifinyeleleka esiphezulu sisuka ku-5696 kbps siye ku-15,3 Mbps.
Ukusetshenziswa kwe-analog pulse modulation (PAM) kwenza i-SHDSL ifane nenani lamazinga e-Ethernet adumile, njenge-gigabit 1000BASE-T (PAM-5), 10-gigabit 10GBASE-T (PAM-16) noma i-industrial single-pair Ethernet 2020BASE -T10L, ethembisayo ngo-1 (PAM-3).
I-SHDSL ngamanethiwekhi e-Ethernet
Kunamamodemu e-SHDSL aphethwe nangalawulwa, kodwa lokhu kuhlukaniswa kuncane okufanayo nokuhlukaniswa okujwayelekile kumadivayisi aphethwe nangalawulwa akhona, ngokwesibonelo, amaswishi e-Ethernet. Umehluko ulele kumathuluzi okumisa nokuqapha. Amamodemu aphethwe alungiswa ngesixhumi esibonakalayo sewebhu futhi angaxilonga nge-SNMP, kuyilapho amamodemu angaphethwe angatholwa kusetshenziswa isofthiwe eyengeziwe ngembobo yekhonsoli (ku-Phoenix Contact lolu wuhlelo lwamahhala lwe-PSI-CONF kanye ne-mini-USB interface). Ngokungafani namaswishi, amamodemu angalawulwa angasebenza kunethiwekhi ene-ring topology.
Uma kungenjalo, amamodemu aphethwe nangaphethwe afana ngokuphelele, okuhlanganisa ukusebenza kanye nekhono lokusebenza kumgomo we-Plug&Play, okungukuthi, ngaphandle kwanoma yikuphi ukulungiselelwa kokuqala.
Ukwengeza, amamodemu angahlonyiswa ngemisebenzi yokuvikela ukuhlinza enekhono lokuyixilonga. Amanethiwekhi e-SHDSL angakha amasegimenti amade kakhulu, futhi amakhondaktha angasebenza ezindaweni lapho ama-voltage akhuphukayo (umehluko ongaba khona obangelwa ukuphuma kombani noma amasekhethi amafushane emigqeni yekhebula eseduze) kungenzeka. I-voltage ebangelwe ingabangela ukugeleza kwemisinga ye-kiloamperes. Ngakho-ke, ukuvikela imishini ezenzakalweni ezinjalo, ama-SPD akhiwe kumamodemu ngendlela yebhodi elikhiphekayo, elingashintshwa uma kunesidingo. Kukumatheminali aleli bhodi lapho kuxhunywe khona ulayini we-SHDSL.
Ama-Topologies
Usebenzisa i-SHDSL phezu kwe-Ethernet, kungenzeka ukwakha amanethiwekhi nganoma iyiphi i-topology: iphuzu-kuya-iphuzu, umugqa, inkanyezi nendandatho. Ngesikhathi esifanayo, kuye ngohlobo lwemodemu, ungasebenzisa imigqa yokuxhumana ye-2-wire kanye ne-4-wire ukuxhumana.
Ama-topology enethiwekhi ye-Ethernet asekelwe ku-SHDSL
Kungenzeka futhi ukwakha izinhlelo ezisabalalisiwe nge-topology ehlanganisiwe. Ingxenye ngayinye yenethiwekhi ye-SHDSL ingaba namamodemu angafika kwangu-50 futhi, kucatshangelwa amandla okusebenza obuchwepheshe (ibanga phakathi kwamamodemu lingama-20 km), ubude bengxenye bungafinyelela ku-1000 km.
Uma imodemu ephethwe ifakwe phezulu kwesegimenti enjalo, khona-ke ubuqotho besegimenti bungatholwa kusetshenziswa i-SNMP. Ngaphezu kwalokho, amamodemu aphethwe futhi angalawulwa asekela ubuchwepheshe be-VLAN, okungukuthi, akuvumela ukuthi uhlukanise inethiwekhi ibe ama-subnets anengqondo. Amadivayisi futhi ayakwazi ukusebenza nezinqubo zokudlulisa idatha ezisetshenziswa ezinhlelweni zesimanje ezishintshayo (i-Profinet, i-Ethernet/IP, i-Modbus TCP, njll.).
Ukubhukha iziteshi zokuxhumana kusetshenziswa i-SHDSL
I-SHDSL isetshenziselwa ukudala iziteshi zokuxhumana ezingasasebenzi kunethiwekhi ye-Ethernet, evamise ukubonwa ngamehlo.
I-SHDSL ne-serial interface
Amamodemu e-SHDSL anesixhumi esibonakalayo seserial anqoba imikhawulo ebangeni, i-topology kanye nekhwalithi ye-conductor ekhona kumasistimu anezintambo zendabuko asekelwe kuma-asynchronous transceivers (UART): RS-232 - 15 m, RS-422 kanye ne-RS-485 - 1200 m.
Kukhona amamodemu anezixhumanisi ze-serial (RS-232/422/485) kuzo zombili izinhlelo zokusebenza ezisebenza emhlabeni wonke nezikhethekile (isibonelo, ze-Profibus). Wonke amadivaysi anjalo ayingxenye "engaphethwe", ngakho-ke ayalungiswa futhi axilongwe kusetshenziswa isofthiwe ekhethekile.
Ama-Topologies
Kumanethiwekhi anesixhumi esibonakalayo seserial, kusetshenziswa i-SHDSL kungenzeka ukwakha amanethiwekhi anephoyinti-kuya-iphuzu, ulayini kanye nenkanyezi topology. Ngaphakathi kwe-linear topology, kungenzeka ukuhlanganisa ama-node angama-255 kunethiwekhi eyodwa (ye-Profibus - 30).
Kuzinhlelo ezakhiwe kusetshenziswa amadivaysi e-RS-485 kuphela, ayikho imikhawulo kuphrothokholi yokudluliswa kwedatha esetshenzisiwe, kodwa izihloko zezindaba zomugqa nenkanyezi azifaneli ku-RS-232 kanye ne-RS-422, ngakho-ke ukusebenza kwamadivayisi wokugcina kunethiwekhi ye-SHDSL enezihloko ezifanayo. kungenzeka kuphela ngemodi ye-half-duplex. Ngesikhathi esifanayo, kumasistimu ane-RS-232 kanye ne-RS-422, ikheli ledivayisi kufanele linikezwe ezingeni lephrothokholi, elingajwayelekile ezindaweni ezivame ukusetshenziswa kakhulu kumanethiwekhi ephoyinti nephoyinti.
Lapho uxhuma amadivaysi anezinhlobo ezahlukene zokusebenzelana nge-SHDSL, kubalulekile ukucabangela iqiniso lokuthi ayikho indlela eyodwa yokusungula uxhumano (ukuxhawula) phakathi kwamadivayisi. Nokho, kusengenzeka ukuhlela ukushintshana kuleli cala; kulokhu, kufanele kuhlangatshezwane nemibandela elandelayo:
- ukuxhumanisa ukuxhumana nokulawula ukudluliswa kwedatha kufanele kwenziwe ezingeni lephrothokholi ehlanganisiwe yokudlulisa imininingwane;
- wonke amadivaysi okuphela kufanele asebenze ngemodi ye-half-duplex, okufanele futhi isekelwe yiphrothokholi yolwazi.
Iphrothokholi ye-Modbus RTU, iphrothokholi evame kakhulu yezindawo zokusebenzelana ezingavumelaniyo, ikuvumela ukuthi ugweme yonke imikhawulo echaziwe futhi wakhe uhlelo olulodwa olunezinhlobo ezahlukene zokuhlangana.
Ama-topology enethiwekhi ye-serial asekelwe ku-SHDSL
Uma usebenzisa izintambo ezimbili i-RS-485 kumishini Ungakha izakhiwo eziyinkimbinkimbi ngokuhlanganisa amamodemu ngebhasi elilodwa kuloliwe we-DIN. Ukunikezwa kwamandla kungafakwa ebhasini elifanayo (kulokhu, wonke amadivaysi anikwa amandla ngebhasi) kanye neziguquli ezibonakalayo zochungechunge lwe-PSI-MOS ukuze kwakhiwe inethiwekhi ehlanganisiwe. Isimo esibalulekile sokusebenza kwesistimu enjalo yijubane elifanayo lawo wonke ama-transceivers.
Izici ezengeziwe ze-SHDSL kunethiwekhi ye-RS-485
Izibonelo zohlelo lokusebenza
Ubuchwepheshe be-SHDSL busetshenziswa kakhulu ezinsizeni zikamasipala eJalimane. Izinkampani ezingaphezu kuka-50 ezihlinzeka ngezinsiza zedolobha zisebenzisa izintambo zethusi ezindala ukuxhuma izinto ezisatshalaliswa kulo lonke idolobha ngenethiwekhi eyodwa. Amasistimu okulawula nokubalwa kwezimali kwamanzi, igesi namandla akhiwe ngokuyinhloko ku-SHDSL. Phakathi kwamadolobha anjalo kukhona i-Ulm, Magdeburg, Ingolstadt, Bielefeld, Frankfurt an der Oder namanye amaningi.
Uhlelo olukhulu kunazo zonke olusekelwe ku-SHDSL lwadalwa edolobheni laseLübeck. Isistimu inesakhiwo esihlanganisiwe esisekelwe ku-Ethernet optical kanye ne-SHDSL, ixhuma izinto ezingu-120 zikude ukusuka kwenye futhi isebenzisa amamodemu angaphezu kuka-50. . Yonke inethiwekhi itholwa kusetshenziswa i-SNMP. Ingxenye ende kunazo zonke ukusuka eKalkhorst ukuya e-Lübeck Airport ingamakhilomitha angama-39 ubude. Isizathu esenza inkampani yeklayenti ikhethe i-SHDSL ukuthi yayingasebenzi ngokwezomnotho ukusebenzisa iphrojekthi ngokuphelele ku-optics, uma kubhekwa ukutholakala kwezintambo zethusi ezindala.
Ukudluliswa kwedatha ngendandatho yesiliphu
Isibonelo esithakazelisayo ukudluliswa kwedatha phakathi kwezinto ezihambayo, njengokwenziwa ezinjinini zomoya noma emishinini emikhulu yokusonta yezimboni. Isistimu efanayo isetshenziselwa ukushintshaniswa kolwazi phakathi kwezilawuli ezitholakala ku-rotor kanye ne-stator yezitshalo. Kulokhu, othintana naye oslayidayo ngendandatho yesiliphu isetshenziselwa ukudlulisa idatha. Izibonelo ezinjengalezi zibonisa ukuthi akudingekile ukuba noxhumana naye omile ukuze udlulise idatha nge-SHDSL.
Ukuqhathanisa nobunye ubuchwepheshe
I-SHDSL vs GSM
Uma siqhathanisa i-SHDSL namasistimu okudlulisa idatha asekelwe ku-GSM (3G/4G), kusho ukuthi ukungabikho kwezindleko zokusebenza okuhlobene nezinkokhelo ezivamile ku-opharetha zokufinyelela kunethiwekhi yeselula kukhulumela i-DSL. Nge-SHDSL, sizimele endaweni ehlanganisayo, ikhwalithi nokuthembeka kwezokuxhumana eziphathwayo endaweni yezimboni, okuhlanganisa ukumelana nokuphazamiseka kazibuthe kagesi. Nge-SHDSL asikho isidingo sokumisa okokusebenza, okusheshisa ukuthunyelwa kwesikhungo. Amanethiwekhi angenantambo abonakala ngokubambezeleka okukhulu ekudluliselweni kwedatha nobunzima bokudlulisa idatha kusetshenziswa ithrafikhi yokusakaza okuningi (Profinet, Ethernet IP).
Ukuphepha kolwazi kukhulumela i-SHDSL ngenxa yokungabikho kwesidingo sokudlulisa idatha nge-inthanethi kanye nesidingo sokumisa ukuxhumana kwe-VPN kwalokhu.
I-SHDSL vs Wi-Fi
Okuningi osekushiwo nge-GSM kungasetshenziswa naku-Wi-Fi yezimboni. Ukungavikeleki komsindo ophansi, ibanga elilinganiselwe lokudluliswa kwedatha, ukuncika ku-topology yendawo, nokubambezeleka ekudlulisweni kwedatha kukhuluma ngokumelene ne-Wi-Fi. I-drawback ebaluleke kakhulu ukuphepha kolwazi lwamanethiwekhi e-Wi-Fi, ngoba noma ubani unokufinyelela ku-medium yokudlulisa idatha. Nge-Wi-Fi sekuvele kuyenzeka ukudlulisa idatha ye-Profinet noma ye-Ethernet IP, okungaba nzima ku-GSM.
I-SHDSL vs Optics
Ezimweni eziningi, i-Optics inenzuzo enkulu kune-SHDSL, kodwa eziningana zezinhlelo zokusebenza i-SHDSL ikuvumela ukuthi wonge isikhathi nemali ekubekeni nasekushiseleni izintambo ze-optical, ukunciphisa isikhathi esisithathayo ukuze kusetshenziswe indawo. I-SHDSL ayidingi izixhumi ezikhethekile, ngoba ikhebula lokuxhumana livele lixhumeke ku-terminal yemodemu. Ngenxa yezakhiwo zemishini yezintambo ze-optical, ukusetshenziswa kwazo kunqunyelwe ezinhlelweni ezibandakanya ukudluliswa kolwazi phakathi kwezinto ezihambayo, lapho ama-conductor ethusi avame kakhulu.
Source: www.habr.com