Siyakwamukela kubalandeli besizindalwazi samathikithi
Namuhla sethula kuwe imigomo ejwayelekile ebaluleke kakhulu emigomeni ye
CCNA
Ngesibusiso sikaNkulunkulu, ake siqale
(((Izisekelo Zenethiwekhi))
I-VPN: Inethiwekhi yangasese yangasese
o Indlela yokubethela iphuzu ukukhomba isiphambano inethiwekhi yomphakathi
I-VOIP: I-Voice over Internet Protocol
o Ukulethwa kokuxhumana ngezwi ngenethiwekhi ye-IP
o isevisi iguqula izwi lakho libe yisiginali yedijithali ehamba nge-inthanethi
SAM: Umphathi we-Akhawunti Yezokuphepha
o Isizindalwazi esiqukethe i-akhawunti yomsebenzisi nezincazelo zokuphepha eqenjini lomsebenzi
I-LAN: Inethiwekhi Yendawo Yasendaweni
o Ukuxhumanisa i-pc emibili noma ngaphezulu namadivayisi ahlobene ngaphakathi kwendawo enomkhawulo
INDODA: Inethiwekhi Yesizinda SeMetropolitan
Okukhulu kune-LAN futhi kuncane kune-WAN
I-WAN: Inethiwekhi Ebanzi Yendawo
o Kusetshenziselwe ukuxhuma ama-LAN ndawonye
I-MAC: Ukulawulwa kokufinyelela kwemidiya
o Ubhekele ikheli le-hardware
Igama Lesizinda:
Igama lewebhusayithi nje ex: www.tedata.net ebizwa ngegama lesizinda.
Igama Sebenza:
o Iseva equkethe amafayela we-Zone wesizinda sekhasimende afaka imininingwane ebalulekile yesizinda njenge (Amarekhodi e-A & MX).
Iseva Yokubamba:
o Iseva equkethe amafayela we-FTP wesizinda samakhasimende futhi angabiwa noma atholakale.
Iseva yemeyili:
o Yiseva okufanele ikhasimende libe nayo uma lifuna ukwakha ama-E-mail ngaphansi kwesizinda salo esidala. ([i-imeyili ivikelwe])
I-HTML: I-HypertextUlimi Lwemakhaphu
Ikhodi elula yokudala amakhasi e-web wonke amaseva noma ngabe isayithi lenziwe lithumela idatha kusiphequluli ngefomethi ye-html
I-NAT: ukuhumusha kwekheli lenethiwekhi
o Ingabe ukuhunyushwa kwekheli lephrothokholi ye-inthanethiIkheli le-IP) esetshenziswa ngaphakathi kwenethiwekhi eyodwa kuya kukheli elihlukile le-IP elaziwa ngaphakathi kwenye inethiwekhi, Inethiwekhi eyodwa ibekwa njengenethiwekhi yangaphakathi kanti enye ingaphandle. Imvamisa, inkampani ibalaza amakheli angaphakathi enethiwekhi kukheli elilodwa noma amaningi angaphandle kwamakheli e-IP bese ihambisa amakheli we-IP womhlaba wonke kumaphakethe angenayo abuyele kumakheli we-IP endawo. Lokhu kusiza ukuqinisekisa ukuphepha njengoba isicelo ngasinye esiphumayo noma esingenayo kufanele sidlule kwinqubo yokuhumusha enikeza nethuba lokuthola noma lokuqinisekisa isicelo noma sokusiqondanisa nesicelo sangaphambilini. I-NAT ibuye igcine nenombolo yamakheli we-IP womhlaba wonke adingwa yinkampani futhi ivumela inkampani ukuthi isebenzise ikheli elilodwa le-IP ekuxhumaneni kwayo nezwe.
Umehluko phakathi kwesigamu se-duplex ne-duplex ephelele
o Duplex
Indlela yokushintshaniswa kwedatha yamamodemu: i-duplex yesigamu noma i-duplex ephelele. Ngokudluliswa kwe-duplex uhhafu, imodemu eyodwa kuphela engathumela idatha ngasikhathi. Ukuthunyelwa okugcwele okungu-duplex kuvumela womabili amamodemu ukuthi athumele idatha ngasikhathi sinye.
o Isigamu esiyimpinda
Imodi inika amandla amadivayisi okuxhumana ukuthumela idatha ngendlela eyodwa ngasikhathi, kusho ukuthi womabili amadivayisi enethiwekhi awakwazi ukuthumela idatha ngasikhathi sinye. Kufana ne-walkie-talkie, munye kuphela umuntu ongakhuluma ngesikhathi.
o I-duplex ephelele
Inika amandla amadivayisi amabili enethiwekhi ukuthumela idatha ngasikhathi sinye futhi ithuthukisa ukusebenza kwenethiwekhi. Kufana nokushayela umngani wakho ucingo ngocingo noma ngomakhalekhukhwini, nobabili niyakwazi ukukhuluma nokulalela ngasikhathi sinye.
Umehluko phakathi kwezimpawu ze-analog nezedijithali.
o Izimpawu ze-Analog
Sebenzisa imisinga kagesi eguquguqukayo eqhubekayo eguquguqukayo ukukhiqiza idatha edluliswayo. Njengoba idatha ithunyelwa kusetshenziswa imisinga eguquguqukayo ohlelweni lwe-analog, kunzima kakhulu ukususa ukuhlanekezelwa komsindo namagagasi ngesikhathi sokudlulisa. Ngalesi sizathu, amasiginali we-analog awakwazi ukwenza ukudluliswa kwedatha esezingeni eliphakeme.
o Izimpawu ezidijithali
Sebenzisa izintambo zedatha kanambambili (0 no-1) ukukhiqiza kabusha idatha edluliswayo. Umsindo nokuhlanekezelwa akunamthelela omncane, okwenza ukudluliswa kwedatha esezingeni eliphakeme kwenzeke. Ukudluliswa kwedatha yedijithali esezingeni eliphakeme le-INS-Net ngesivinini esikhulu kuzuzisa kakhulu ekudluliseni kusetshenziswa amakhompyutha kwazise amakhompyutha ngokwawo asebenzisa amasiginali edijithali ukucubungula ulwazi.
Umehluko phakathi kwe-Firewalls ne-Proxy
o I-Firewall
Ingxenye yohlelo lwekhompyutha noma inethiwekhi evikela uhlelo ngokuvimbela ukufinyelela okungagunyaziwe kwi-inthanethi. Iseva elibamba luhlobo olulodwa lwe-firewall.
Umsebenzi we-Basic Firewall
I-firewall isebenza ngokuhlola iphakethe ngalinye lemininingwane ethunyelwe phakathi kwekhompyutha evikelwe namakhompyutha ngaphandle kwenethiwekhi yendawo. Amaphakethe angahlangabezani nemithetho ethile avinjiwe.
o Ezinye Izinhlobo ze-Firewall
Izicishamlilo eziningi yizinhlelo zesoftware esikhundleni samakhompyutha ahlukile njengeseva elibamba. Uhlelo luqapha ithrafikhi ye-inthanethi yekhompyutha futhi luvumela noma luphike ukufinyelela ngokuya ngemithetho ebekwe ngumsebenzisi.
o Iseva Yommeleli
Iseva elibamba yikhompyutha ehleli phakathi kwenethiwekhi yendawo nayo yonke i-inthanethi. Konke ukufinyelela kwangaphandle kunethiwekhi kumele kudlule kule seva.
o Izinzuzo Zommeleli
Ngoba wonke umgwaqo oya kumakhompiyutha avikelwe kumele udlule kuseva elibamba, abasebenzisi bangaphandle abakwazi ukuthola amakheli wenethiwekhi athile wamakhompiyutha kunethiwekhi yendawo, engeza isendlalelo esingeziwe sokuphepha.
o Ububi bommeleli
Umnikazi we-proxy server angabona wonke umgwaqo ophakathi kwenethiwekhi ne-inthanethi engaphandle, engakhawulela ubumfihlo babasebenzisi ngabodwa ngaphakathi kommeleli. Futhi, amaseva we-proxy adinga ukusethwa okukhulu futhi ngenxa yalokho awasebenzi kumakhompyutha awodwa.
Isilinganiso sokuya kumsindo
o (Imvamisa efushanisiwe i-SNR noma i-S / N) isilinganiso sokulinganisa ukuthi isignali yonakaliswe kangakanani umsindo. Kuchazwa njengokulinganisa kwamandla esignali emandleni omsindo okonakalisa isignali.
o Isilinganiso sivame ukukalwa ngama-decibel (dB).
Yini lokhu: SNR Margin and Line Attenuation? Ngabe kuyasiza ukwazi ikhwalithi yami yomugqa?
o SNR
I-SNR isho iSignal to Noise Ratio. Mane ubeke i-value Signal nge-Noise Value bese uthola i-SNR. Udinga i-SNR ephezulu ngokuxhumeka okuzinzile. Ngokuvamile, isignali ephakeme kunani lomsindo lizoholela emaphutheni amancane.
• 6bB. noma ngezansi = Kubi futhi ngeke kutholakale ukuvumelanisa komugqa nokunqanyulwa okuvamile
• 7dB-10dB. = Kulungile kepha akushiyi indawo eningi yokungafani kwezimo.
• 11dB-20dB. = Kuhle ngezinkinga zokunqamula okuncane noma cha
• 20dB-28dB. = Kuhle kakhulu
• 29dB. noma ngaphezulu = Okuvelele
Qaphela ukuthi amamodemu amaningi abonisa inani njenge-SNR Margin hhayi i-SNR emsulwa.
o I-SNR Margin
ungacabanga ngomugqa we-SNR njengesilinganiso sekhwalithi yesevisi; ichaza amandla esevisi okusebenza ngaphandle kwephutha ngesikhathi sokuqhuma komsindo.
Lesi isilinganiso somehluko phakathi kwe-SNR yakho yamanje ne-SNR okudingeka ukugcina insizakalo ethembekile ngejubane lakho lokuxhuma. Uma i-SNR yakho isondele kakhulu kubuncane obudingekayo be-SNR, kungenzeka ukuthi ubhekane nezinkinga zokuxhuma ngezikhathi ezithile, noma ukwehla. Udinga umkhawulo ophakeme ukuze uqinisekise ukuthi ukuqhuma kokuphazamiseka akubangeli ukunqanyulwa okungapheli.
Nge-broadband yendabuko, iphakama i-SNR Margin, iba ngcono. NgeMaxDSL isivinini esisheshayo sitholakala kuphela njengokuhweba ngalokho umugqa wakho ongakusekela ngokuthembekile. I-Target SNR Margin icishe ibe yi-6dB. Uma i-broadband yakho inikezwa ngenethiwekhi ye-LLU (Local Loop Unbundled), le Margin target le-SNR ingaba phezulu njenge-12dB.
Ukuncishiswa komugqa
Ngokuvamile, ukunciphisa umzimba ukulahleka kwesiginali ngebanga. Ngeshwa, ukulahleka kwe-dB akuxhomekile nje ebangeni. Futhi kuya ngohlobo lwentambo negeji (engahluka kubude bekhebuli), inombolo nendawo amaphuzu okuxhuma kukhebula.
o 20bB. Futhi ngezansi = Okuvelele
o 20dB-30dB. = Kuhle kakhulu
o 30dB-40dB. = Kuhle kakhulu
o 40dB-50dB. = Kuhle
o 50dB-60dB. = Kubi futhi kungahle kube nezinkinga zokuxhuma
o 60dB. Futhi ngaphezulu = Kubi futhi kuzobhekana nezinkinga zokuxhuma
Ukuncishiswa komugqa nakho kuthinta isivinini sakho.
o 75 dB +: Iphuma ebangeni le-broadband
o 60-75 dB: max ishesha ifike ku-512kbps
o 43-60dB: max ishesha ifike ku-1Mbps
o 0-42dB: shesha ufike ku-2Mbps +
Uma ucabanga ukuthi i-SNR yakho iphansi, ungenza okulandelayo ukukhulisa i-SNR yakho yilokhu okulandelayo:
Thola ukuthi ucingo lwefoni lungena kuphi ekhaya lakho
Yilandele yonke indlela ubuyele ebhokisini lokuhlangana
Bheka ukuthi ikhebula lisesimweni esihle yini - alikho ngokweqile, alinazinsimbi, ucingo aludluli kunoma yiziphi izintambo zikagesi noma izintambo zesathelayithi njll.
Ebhokisini lokuhlangana, hlola ukuxhumana. Ingabe i-corroded, i-oxidized? Uma kunjalo, kubhale phansi.
Umehluko phakathi kwe-RJ11 ne-RJ45
o RJ
Ijack ebhalisiwe ingumzimba omisiwe isikhombikubona senethiwekhi- womabili ukwakhiwa kwejack nephethini yezintambo - yokuxhuma ezokuxhumana ngocingo noma okokusebenza kwedatha kusevisi enikezwe yi inkampani yenethiwekhi yendawo or othwala ibanga elide.
o RJ11
Uhlobo lwejack olujwayele ukusetshenziselwa ukuxhuma izingcingo ze-analogue, amamodemu nemishini yefeksi kulayini wezokuxhumana.
o RJ45
Ingabe uhlobo olujwayelekile lokuxhuma lwezintambo zenethiwekhi. Izixhumi ze-RJ45 zivame ukubonwa nge- Ethernetizintambo namanethiwekhi.
Izixhumi ze-RJ45 zinezikhonkwane eziyisishiyagalombili lapho izintambo zocingo zesixhumi esibonakalayo se-cable zisebenza khona ngogesi. Ama-pinouts ajwayelekile we-RJ-45 achaza ukuhlelwa kwezintambo ngazinye ezidingekayo lapho kufakwa izixhumi kukhebula.
Ikhebula le-Ethernet - Umdwebo Wokufaka Amakhodi Umbala
o Imidwebo elula yokukhipha izinhlobo ezimbili zezintambo ze-UTP Ethernet futhi ubuke ukuthi amakomidi angenza kanjani ikani lezikelemu ngawo. Nayi imidwebo:
Qaphela ukuthi izikhonkwane ze-TX (transmitter) zixhunywe kuzikhonkwane ze-RX (receiver) ezihambisanayo, kanye nokuhlanganisa nokukhipha ku-minus. Futhi ukuthi kufanele usebenzise ikhebula le-crossover ukuxhuma amayunithi ane-interface efanayo. Uma usebenzisa ikhebula eliqonde ngqo, enye yamayunithi amabili kufanele, empeleni, yenze umsebenzi wokuwela.
o Kusebenza izindinganiso ezimbili zekhodi yombala: i-EIA / TIA 568A ne-EIA / TIA 568B. Amakhodi akhonjiswa kakhulu ngama-RJ-45 jacks ngokulandelayo (ukubuka kuvela ngaphambili kwamajeke):
o Uma sisebenzisa ikhodi yombala engu-568A futhi sikhombisa zonke izintambo eziyisishiyagalombili, ukuphuma kwethu kubukeka kanjena:
o Qaphela ukuthi izikhonkwane ezingu-4, 5, 7, no-8 namabhangqa aluhlaza okwesibhakabhaka nansundu awasetshenziswa kunoma yiliphi izinga. Ngokuphambene nalokho ongakufunda kwenye indawo, lezi zikhonkwane nezintambo akusetshenziswanga noma akudingeki ukuthi kusetshenziswe ukuphindaphindeka okungu-100BASE-TX — kumosheke kalula nje.
o Nokho, izintambo zangempela azilula kangako ngokomzimba. Emidwebeni, izintambo eziwolintshi azikho eduze. Umbhangqwana oluhlaza okwesibhakabhaka ubheke phansi. Iziphetho ezingakwesokudla zifana namajack we-RJ-45 kanti ama-left amaphethelo awahambisani. Isibonelo, uma siguqulela ohlangothini lwesobunxele lwentambo “eqondile” engu-568A ukufanisa u-568A jack – faka i-180 ° twist kuyo yonke ikhebula kusukela ekugcineni kuze kube sekupheleni – bese sijija ndawonye bese sihlela kabusha amabhangqa afanele, sithola ama-can-of-worms alandelayo:
Lokhu kuqhubeka kugcizelela, ngiyethemba, ukubaluleka kwegama elithi “twist” ekwenzeni izintambo zenethiwekhi ezizosebenza. Awukwazi ukusebenzisa ikhebula locingo olungasonteki olucijile ngekhebula lenethiwekhi. Ngaphezu kwalokho, kufanele usebenzise izintambo ezimbili ezisontekile ukuxhuma iqoqo lezikhonkwane zokudlulisela kuzikhonkwane zazo ezihambelana nazo. Awukwazi ukusebenzisa ucingo kusuka kubhangqa elilodwa nolunye ucingo oluvela kokunye okuhlukile.
o Ukugcina le migomo engenhla engqondweni, singenza lula umdwebo wekhebula eliqondile le-568A ngokungavuleki izintambo, ngaphandle kwe-180 ° twist kuyo yonke ikhebula, futhi sigobise imikhawulo phezulu. Ngokunjalo, uma sishintshanisa ngababili abahlaza kanye nabolintshi kumdwebo we-568A sizothola umdwebo owenziwe lula wekhebula le-568B eliqonde ngqo. Uma siwela ngazimbili eziluhlaza nezolintshi kumdwebo we-568A sizofika kumdwebo owenziwe lula wekhebula le-crossover. Bobathathu baboniswe ngezansi.
o Isivinini sokudlulisa seCat 5, Cat 5e, Cat 6 network cable
Izintambo ze-Cat 5 ne-Cat 5e UTP zingasekela i-10/100/1000 Mbps Ethernet. Yize ikhebuli leCat 5 lingasekela ngezinga elithile kuGigabit Ethernet (1000 Mbps), lenza ngaphansi kwezinga elijwayelekile phakathi kwezimo zokudluliswa kwedatha ephezulu.
Ikhebula le-Cat 6 UTP lenzelwa ukukhomba ku-Gigabit Ethernet nokubuyela emuva okuhambisana ne-10/100 Mbps Ethernet. Isebenza kangcono ikhebula le-Cat 5 ngezinga eliphakeme lokudlulisa nephutha lokuhambisa eliphansi. Uma uhlela ukuba nenethiwekhi yeGigabit, funa izintambo zeCat 5e noma zeCat 6 UTP.
Iphrothokholi ichaza isethi ejwayelekile yemithetho nezimpawu ezisetshenziswa amakhompyutha kunethiwekhi ukuxhumana.
Imodeli ye-TCP / IP, noma i-internet protocol suite
Ichaza isethi yemihlahlandlela yokuklama ejwayelekile nokusetshenziswa kwezivumelwano ezithile zenethiwekhi ukunika amandla amakhompyutha ukuxhumana ngenethiwekhi
I-TCP / IP ihlinzeka ngokuxhumeka kokuphela kokugcina okucacisa ukuthi idatha kufanele ibhekiswe kanjani, idluliselwe, idluliselwe futhi yamukelwe lapho iya khona
I-TCP: umthetho olandelwayo wokulawula ukudlulisa
Nikeza ukulethwa okuthembekile kwedatha
I-UDP: iphrothokholi yedathagram yomsebenzisi>
Ivumela i-datagram ukuthi ishintshane ngaphandle kokuvuma
IP: I-Internet Protocol
o IP ikheli lekompyutha noma enye idivayisi yenethiwekhi kunethiwekhi esebenzisa i-IP noma i-TCP / IP. Isibonelo, inombolo "166.70.10.23" iyisibonelo sekheli elinjalo. Lawa makheli ayafana namakheli asetshenziswa ezindlini futhi asiza idatha ukuthi ifinyelele lapho iya khona kunethiwekhi.
Kunamakheli e-IP amaningi asetshenzisiwe noma abelwe ngokuzenzakalela kunethiwekhi. Ngokwesibonelo:
166.70.10.0 0 ikheli elenziwa ngokuzenzakalela lenethiwekhi.
166.70.10.1 1 ikheli elisetshenziswa kakhulu elisetshenziswa njengesango.
166.70.10.2 2 futhi ikheli elijwayele ukusetshenziselwa isango.
166.70.10.255 255 inikezwa ngokuzenzakalela kumanethiwekhi amaningi njengekheli lokusakaza.
I-DHCP: I-Dynamic host host configuration protocol
Inombolo ye-Port
- Iklayenti le-DHCP 546 / TCP UDP
- Iseva ye-DHCP 546 / TCP UDP
Ivumela iseva ukuthi isabalalise ngamandla ikheli le-IP futhi kunemininingwane eminingi iseva ye-DHCP engayinikeza umphathi lapho i-Host isicela ikheli le-IP kwiseva ye-DHCP njengekheli le-IP, imaski ye-subnet, isango elizenzakalelayo, i-DNS, igama lesizinda , WINS imininingwane.
I-DNS: insiza yegama lesizinda (iseva)
o Isitholi sezinsizakusebenza
o Ixazulula igama lokusingathwa kuma-IPs nokunye ukuhlakanipha
o Sombulula igama lesizinda eliqeqeshiwe ngokuphelele (i-FQDN)
o Siqukethe:
Irekhodi: sombulula igama lesizinda kukheli le-IP
Irekhodi le-MX: sombulula iseva yemeyili kukheli le-IP
Ukurekhodwa kwe-PTR: okuphambene nerekhodi le-A nerekhodi le-MX, Xazulula ikheli le-IP egameni lesizinda noma kuseva yeposi
I-PPP: Khomba eProtocol Protocol
Iphrothokholi evumela ikhompyutha ukuxhuma kwi-Intanethi ngokuxhumeka kokudayela futhi ijabulele iningi lezinzuzo zokuxhumeka okuqondile; kufaka phakathi ikhono lokuqalisa ukuphela kokuqhafaza okufana ne-Internet Browsers. I-PPP imvamisa ithathwa njengephakeme kune-SLIP, ngoba ifaka ukutholwa kwephutha, ukucindezelwa kwedatha, nezinye izinto zamaphrothokholi ezokuxhumana anamuhla i-SLIP engenawo.
I-PPPoE: Khomba ukukhomba umthetho olandelwayo ngaphezulu kwe-Ethernet
o I-protocol yenethiwekhi yokugoqa ifreyimu yokukhomba iprotocol ye-protocol (PPP) ngaphakathi kozimele be-Ethernet.
o Isetshenziswa kakhulu ngezinsizakalo ze-DSL lapho abasebenzisi ngabanye bexhumana ngamanethiwekhi we-Ethernet alula.
I-SMTP: iphrothokholi yokudlulisa imeyili elula
o Inombolo ye-Port 25 / TCP UDP
Ingabe umsebenzisi ukuthumela imeyili (ephumayo)
I-POP3: umthetho olandelwayo weposi
o Inombolo ye-Port 110 / TCP
o Kusetshenziswa ukuthola imeyili (engenayo)
I-FTP: iphrothokholi yokudlulisa ifayela
o Inombolo ethekwini 21 / TCP
Masidlulise amafayela futhi kungenza lokhu phakathi kwanoma yimuphi umshini emibili
I-FTP akuyona nje umthetho olandelwayo, futhi uhlelo
o Okufana nokuthi: yenza umsebenzi wefayela ngesandla
o Ivumela ukufinyelela kuzo zombili izinkomba namafayela
Kuvikelekile ngakho-ke abasebenzisi kumele bafakwe ukungena ngemvume kokuqinisekisa (kuvikelwe ngegama lomsebenzisi nephasiwedi okusetshenziswa ngabaphathi bohlelo ukukhawulela ukufinyelela)
o I-FTP inketho okufanele uyicabangele uma ngabe udinga ukuthumela nokwamukela amafayela amakhulu (ngoba ama-ISP amaningi awavumeli amafayela amakhulu kuno-5 MB ukuthi athunyelwe nge-imeyili)
I-FTP iyashesha kune-imeyili, okungenye yezizathu zokusebenzisa i-ftp ukuthumela noma ukwamukela amafayela amakhulu
I-SNMP: inqubo elula yokuphathwa kwenethiwekhi
o Inombolo ethekwini 161 / UDP
o Qoqa uphinde usebenzise imininingwane ebalulekile yenethiwekhi
Noma isetshenziselwe ukuphatha amanethiwekhi asuselwa ku-TCP / IP kanye ne-IPX.
I-HTTP: iphrothokholi yokudlulisa i-hypertext
o Inombolo ye-Port 80 / TCP
Protocol esezingeni lesicelo, isetshenziselwa ukubuyisa izinsizakusebenza ezixhunyanisiwe ezibizwa ngama-hyper text documents ekusungulweni kweWorld Wide Web
o I-HTTP /1.0 isebenzise ukuxhumana okuhlukile kwemibhalo yonke
o I-HTTP /1.1 ingasebenzisa futhi ukuxhumana okufanayo ukulanda.
I-LDAP: umthetho olula wokufinyelela kusiqondisi
o Inombolo ye-Port 389 / TCP
o Kuyindlela elandelwayo yamakhasimende yokubuza nokuphatha imininingwane kusevisi yomkhombandlela ngaphezulu kwe-TCP port port 389
I-OSPF: vula indlela emfushane kuqala
o Uqukethe izindawo nezinhlelo ezizimele
o kunciphisa umzila wokubuyekeza umzila
o Ivumela ukwehla
o Unokubalwa okungenamkhawulo kwe-hop
o Ivumela ukuthunyelwa kwabathengisi abaningi (okuvulekile okujwayelekile)
o Ukusekela i-VLSM
I-ISDN: Inethiwekhi edijithali yezinsizakalo ezihlanganisiwe
o Umhlaba jikelele ukuxhumana ejwayelekile ngokuthumela izwi, ividiyo, Futhi idatha ngaphezulu kwezintambo zocingo ezidijithali noma izintambo ezijwayelekile zocingo. I-ISDN izisekelo amazinga wokudluliswa kwedatha ka 64 I-Kbps (64,000 izingcezu ngomzuzwana).
Kunezinhlobo ezimbili ze-ISDN:
o Isilinganiso Esibonakalayo Sokuxhumana (BRI) - iqukethe ama-64-Kbps amabili Iziteshi ze-B Futhi eyodwa Isiteshi se-D yokudlulisa imininingwane yokulawula.
o Isilinganiso Esiyinhloko Sokuxhumana (PRI) - iqukethe iziteshi ezingama-23 B nesiteshi esisodwa se-D (i-US) noma iziteshi ezingama-30 ze-B nesiteshi esisodwa se-D (iYurophu).
o Uhlobo lwangempela lwe-ISDN lisebenzisa ukudluliswa kwe-baseband. Enye inguqulo, ebizwa I-B-ISDN, isebenzisa ukudluliswa kwe-broadband futhi iyakwazi ukuxhasa amazinga okudlulisa ama-1.5 Mbps. I-B-ISDN idinga izintambo ze-fiber optic futhi ayitholakali kabanzi.
Umugqa Led
o Ngumugqa wocingo oqashiselwe ukusetshenziswa ngasese, Kwezinye izimo, ubizwa ngokuthi ulayini ozinikele. Ulayini oqashisiwe uvame ukuqhathaniswa nolayini oshintshiwe noma umugqa wokudayela.
o Ngokuvamile, izinkampani ezinkulu ziqasha imigqa eqashiwe kusuka kubathwali bemiyalezo yocingo (njenge-AT & T) ukuxhuma izindawo ezahlukahlukene enkampanini yabo. Enye indlela ukuthenga nokugcina imigqa yabo yangasese noma, mhlawumbe, ukushintsha, ukusebenzisa imigqa yomphakathi enezinqubo ezivikelekile zemiyalezo. (Lokhu kubizwa ngokuthi ukuthungwa).
I-loop yendawo
Ngocingo, iluphu yendawo ukuxhumana okunezintambo okuvela enkampanini yezingcingo ihhovisi eliphakathiendaweni yezingcingo zamakhasimende ayo emakhaya nasemabhizinisini. Lokhu kuxhumana kuvame ukuba sezintanjeni zethusi ezibizwa umbhangqwana osontekile. Uhlelo ekuqaleni lwalwenzelwe ukudluliswa kwezwi kusetshenziswa kuphela I-analog ubuchwepheshe bokudlulisa esiteshini sezwi esisodwa. Namuhla, ikhompyutha yakho i-modem yenza ukuguqulwa phakathi kwamasignali we-analog namasiginali edijithali. Ngenethiwekhi Yedijithali Ehlanganisiwe YezinsizakaloI-ISDN) noma i-Digital Subscriber Line (DSL), iluphu yendawo ingakwazi ukuthwala amasiginali edijithali ngqo nangomkhawulokudonsa ophakeme kakhulu kunowezwi kuphela.
I-Spyware
Ingabe uhlobo lwe-malware olungafakwa kulo amakhompyutha, futhi yini eqoqa izingcezwana zolwazi ezimayelana nabasebenzisi ngaphandle kolwazi lwabo? Ukuba khona kwe-spyware kuvame ukufihlwa kumsebenzisi, futhi kungaba nzima ukukuthola. Imvamisa, i-spyware ifakwa ngasese kumsebenzisi ikhompyutha yomuntu siqu. Kwesinye isikhathi, noma kunjalo, ama-spywares afana ne-ukhiye abagawuli
afakwe umnikazi wendawo okwabelwana ngayo, yebhizinisi, noma ikhompyutha yomphakathi ngenhloso yokuqapha ngasese abanye abasebenzisi.
Ngenkathi igama elithi spyware liphakamisa isoftware ehlola ngasese ikhompyutha yomsebenzisi, imisebenzi ye-spyware inweba ngaphezu kokuqapha okulula. Izinhlelo zeSpyware zingaqoqa izinhlobo ezahlukahlukene ze ulwazi lomuntu siqu, njengemikhuba yokushweza i-Inthanethi namasayithi avakashelwe, kodwa futhi kungaphazamisa ukulawula komsebenzisi ikhompyutha ngezinye izindlela, njengokufaka isoftware eyengeziwe nokuqondisa kabusha Isiphequluli sewebhu umsebenzi. I-Spyware yaziwa ngokushintsha amasethingi ekhompyutha, okuholela ekutheni isivinini sokuxhuma sihambe kancane, amakhasi ahlukene asekhaya, kanye / noma ukulahleka kwe- Internet ukuxhumeka noma ukusebenza kwezinye izinhlelo. Emzameni wokwandisa ukuqonda kwe-spyware, ukuhlukaniswa okusemthethweni ngokwengeziwe kwezinhlobo zesoftware ezifakiwe kunikezwa yileli gama isoftware ehlasela ubumfihlo.
o Ngokuphendula ukuvela kwe-spyware, sekuvele imboni encane esebenza i-anti-spyware isoftware. Ukuqalisa isoftware elwa ne-spyware sekuyinto eyaziwayo kabanzi ye- ukuphepha kwekhompyutha yamakhompyutha, ikakhulukazi lawo asebenzayo Microsoft Windows. Iziphathimandla eziningi zishaye imithetho elwa ne-spyware, evame ukukhomba noma iyiphi isoftware efakwe ngasese ukulawula ikhompyutha yomsebenzisi.
o I-Universal Serial Bus (i-USB)
o I-Universal Serial Bus (i-USB) iqoqo lezincazelo zokuxhuma ezakhiwe yi-Intel ngokubambisana nabaholi bemboni. I-USB ivumela ukushesha, ukuxhumana okulula kwemingcele kwi-PC. Lapho ixhunyiwe, yonke into ilungiselela ngokuzenzakalela. I-USB ukuxhumana okuphumelele kakhulu emlandweni wekhompiyutha yomuntu siqu futhi sekufudukele kumthengi electronics (CE) nakwimikhiqizo yeselula.
o Amanothi abalulekile
Isivinini sokulayisha etafuleni elingenhla sibalwa yiKilobyte (8 bit = 1 byte).
Isivinini sokulanda etafuleni elingenhla sibalwa yiKilobyte (KB).
Amadivayisi enethiwekhi
Hub
o Uhlobo olungenangqondo lwedivayisi yokuxhumana.
o Sebenzisa ungqimba lomzimba (ungqimba 1).
o Ithatha idatha ethekwini elilodwa bese iyidlulisa iphuma kuyo yonke enye itheku, ngakho-ke noma yiluphi ulwazi oluthunyelwa noma olutholwa yinoma iyiphi i-PC eyodwa kuHub ludluliselwa kuyo yonke enye i-PC, lokhu kubi kwezokuphepha.
o Isebenzisa ububanzi obuningi bebhendi kunethiwekhi, njengoba amakhompyutha kufanele athole idatha angayidingi.
Shintsha (Ibhuloho)
o Uhlobo oluthe xaxa lwedivayisi yokuxhumana.
o I-Multi-Port Bridge isebenza kungqimba yokuxhumanisa idatha (ungqimba 2).
Yazi ikheli le-MAC le-PC ngayinye, ngakho-ke lapho idatha ingena ku-switch ithumela kuphela idatha emuva ethekwini elinikezwe ikheli le-MAC lekhompyutha.
o Joyina amakhompyutha amaningi ndawonye ngaphakathi kwenethiwekhi yendawo eyodwa (i-LAN) noma inethiwekhi efanayo.
o Shintsha igcina ububanzi beBhendi yenethiwekhi nokusebenza ngokujwayelekile okungcono kuneHub.
router
o Uhlobo oluhlakaniphe kakhulu lwedivayisi yokuxhumana.
o Sebenzisa ungqimba lwenethiwekhi (ungqimba 3).
o I-Router ingafunda ikheli le-IP le-PC ngayinye kanye nenethiwekhi ngayinye, ngakho-ke i-router ingathatha ibhendi yangaphakathi yethrafikhi lapho iya khona ku-inthanethi futhi uyihambise kusuka kunethiwekhi yakho yangaphakathi iye kunethiwekhi yangaphandle.
o Joyina amanethiwekhi amaningi anezintambo noma angenantambo ndawonye, okusho ukuthi axhumanisa amanethiwekhi njengeSango way.
Abaphindaphindayo
o Okuphindayo kuyinsimbi eyenza ukuthi kudlule ubude obubekiwe obubekwe yizinga lenethiwekhi. Ukwenziwa kukhulisa futhi kuvuselele isignali kagesi.
o Futhi iyakwazi ukufaka ingxenye ehlulekayo (isibonelo, ikhebula evulekile) nokuvumelanisa imidiya emibili ehlukile ye-Ethernet. (Isibonelo i-10base2 ebheke ku-10BaseT). Lokhu kusetshenziswa kokugcina okwamanje okuyinhloko.
I-DSLAM: I-Digital Subscriber Line Access Multiplexer
o Yithuluzi lenethiwekhi, elisendaweni yokushintshana ngocingo kwabahlinzeki besevisi
o Ixhuma imigqa yamakhasimende amaningi abhalisile edijithali (ama-DSL) kulayini we-single - High - Speed Internet back back line ngokusebenzisa amasu we-multiplexing.
Ngokuya nge-OSI - Layer Model, i-DSLAM isebenza njengokushintshwa kwenethiwekhi okukhulu, ngakho-ke ukusebenza kusendlalelo 2, ngakho-ke ayikwazi ukuphinda ihambise kabusha ithrafikhi phakathi kwamanethiwekhi amaningi we-IP.
modem
o Modulator / Demodulator: imodem iguqula (imodulates) imininingwane yedijithali ibe isignali ye-analogue engathunyelwa kulayini wonkana wocingo. Iphinda futhi isuse phansi isignali ye-analogue eyitholayo kulayini wocingo, iguqule imininingwane equkethwe kusiginali ibuyele kulwazi lwedijithali.
I-PSTN (inethiwekhi yocingo eshintshiwe yomphakathi)
o Iqoqo lomhlaba wonke lezingcingo ezixhumene nezwi eziqondiswe ngezwi, ezentengiselwano kanye nezikahulumeni, kubizwa nangokuthi yi-Plain Old Telephone Service (POTS). Ukuhlanganiswa kwamanethiwekhi ocingo ashintshana ngesifunda okuguquke kusukela ezinsukwini zika-Alexander Graham Bell ("Doctor Watson, woza lapha!"). Namuhla, icishe ibe yidijithali ngokuphelele kwezobuchwepheshe ngaphandle kwesixhumanisi sokugcina esivela ehhovisi lezingcingo eliphakathi (lendawo) nomsebenzisi.
o Ngokuhlobene ne-Intanethi, i-PSTN empeleni inikezela ngebanga elide le-Intanethi ingqalasizinda. Ngoba abahlinzeki bezinsizakalo ze-Intanethi I-ISPikhokhela abahlinzeki bamabanga amade ukufinyelela kwingqalasizinda yabo futhi babelane ngamasekethe kubasebenzisi abaningi ngokusebenzisa iphakethe-Ukushintsha, abasebenzisi be-Intanethi bayakugwema ukukhokha imali ekhokhwayo yokusebenzisa noma ngubani ngaphandle kwama-ISP abo.
Ukufinyelela kwe-inthanethi kwe-Broadband
o Ngokuvamile kufushaniselwe ku- “broadband” nje, ukuxhumana okuphezulu kwesilinganiso sedatha ku- internet - Kuqhathaniswa ngokujwayelekile nokufinyelela usebenzisa i- Imodemu engu-56k.
o I-Broadband ivame ukubizwa "ngejubane eliphezulu" ukufinyelela kwi-Intanethi, ngoba imvamisa inezinga eliphezulu lokudluliswa kwedatha. Ngokuvamile, noma yikuphi ukuxhumana nekhasimende lama-256 Kbit / s (0.25 Mbit / s) noma ngaphezulu kubhekwa njengokufinyeleleka kwe-inthanethi nge-Broadband.
Umqondo we-DSL
I-DSL: umugqa wobhalisile wedijithali
o Ingabe isevisi ye-Inthanethi esheshayo efana nekhebula le-Inthanethi, i-DSL ihlinzeka ngezingcingo ezihamba ngesivinini esikhulu phezu kwezingcingo ezijwayelekile kusetshenziswa ubuchwepheshe be-broadband, ubuchwepheshe be-DSL buvumela i-Inthanethi nensizakalo yocingo ukuthi isebenze kulayini wefoni ofanayo ngaphandle kokudinga amakhasimende ukuthi anqamule izwi noma i-Intanethi ukuxhumana.
o Kunezinhlobo ezimbili zamasu we-DSL
o Okungafani: ADSL, RADSL, VDSL
o I-Symmetric: SDSL, HDSL, SHDSL
I-ADSL: ulayini wobhalisile wedijithali ongalinganiselwe
o Ihlinzeka ngamanani aphakeme kakhulu ohlangothini olungaphansi kunolwenyuka
o I-ADSL ihlukanisa umkhawulokudonsa wentambo esontekile yamapheya amabili (i-MHZ eyodwa) ngamaqembu amathathu
Ibhendi yokuqala phakathi kuka-1 - 0 KHZ isetshenziselwa insizakalo ejwayelekile yocingo esebenzisa leyo (25 KHZ) kanti enye enye isetshenziswa njengebhendi yokuqapha ukuhlukanisa ishaneli yezwi nesiteshi sedatha
o Ibhande lesibili 2 - 25 KHZ
o Isetshenziselwa ukuxhumana okuphezulu
o 3rd band 200 - 1000 KHZ isetshenziselwa ukuxhumana okuphansi
I-RADSL: isilinganiso somugqa wobhalisile we-asymmetrical digital
o Ngabe ubuchwepheshe bususelwa ku-ADSL, kuvumela amazinga ehlukene wedatha ngokuya ngohlobo lwezwi lokuxhumana, idatha, i-multimedia nokunye
I-HDSL: isilinganiso esiphakeme se-DSL
I-HDSL isebenzisa ukufaka ikhodi kwe-2 kwe-BIQ okungenzeki kalula ekunciphisweni
Izinga ledatha lingu-2 Mbps lingatholakala ngaphandle kokuphinda futhi kuze kufike ebangeni elingu-3.6 Km
o I-HDSL isebenzisa izintambo ezimbili ezisontekile ukufeza ukudluliswa okugcwele.
I-SDSL: i-DSL ehambisanayo
o Iyafana ne-HDSL kepha isebenzisa ikhebula elilodwa elisontekile
o I-SDSL isebenzisa ukukhanselwa kwe-echo ukudala ukuhanjiswa okugcwele
I-VDSL: isilinganiso esiphakeme kakhulu se-DSL
o Ifana ne-ADSL
o Kusetshenziswe ikhebula le-coaxial, optical noma ikhebula le-twisted elisebangeni elifushane (300m -1800m)
o Inqubo yokushintshashintsha yi-DMT enezinga elincane lama-50 - 55 Mbps wehla nomfula no-1.55 - 2.5 Mbps wenyukelayo
o Amapharamitha wokucushwa
I-VPI ne-VCI: Isihlonzi se-Virtual Path & Isihlonzi Sesiteshi Esibonakalayo
o Isetshenziselwa ukukhomba indawo elandelayo yeseli njengoba idlula ochungechungeni lokushintsha kwe-ATM kusendleleni ebheke lapho iya khona
I-PPPoE: Khomba ukukhomba umthetho olandelwayo ngaphezulu kwe-Ethernet
o Ingabe umthetho olandelwayo wenethiwekhi wokufaka iphoyinti lokukhomba iprothokholi (PPP) ngaphakathi kozimele be-Ethernet
o Isetshenziswa kakhulu ngezinsizakalo ze-DSL lapho abasebenzisi ngabanye bexhumana ngamanethiwekhi we-Ethernet alula
MTU: Ubuningi Unit Transmission
o Ekuxhumaneni kwamakhompiyutha, igama elithi Maximum Transmission Unit (MTU) lisho usayizi (ngama-byte) we-PDU omkhulu kunayo yonke lapho ungqimba olunikeziwe lwephrothokholi yezokuxhumana lungadlulela phambili. Imingcele ye-MTU imvamisa ivela ngokuhlangana ne-interface yokuxhumana (i-NIC, i-serial port, njll.). I-MTU ingahle ilungiswe ngamazinga (njengoba kunjalo nge-Ethernet) noma inqunywe ngesikhathi sokuxhuma (njengoba kuvamise ukwenzeka ngezixhumanisi ze-serial point-to-point). I-MTU ephakeme iletha ukusebenza kahle okukhulu ngoba iphakethe ngalinye lithwala idatha eyengeziwe yomsebenzisi ngenkathi amaphrothokholi angaphezulu, njengamakhanda noma ukubambezeleka kwephakethe ngakunye kuhlala kulungisiwe, futhi ukusebenza kahle okuphezulu kusho ukuthuthuka okuncane kokungena kwe-protocol yenqwaba. Kodwa-ke, amaphakethe amakhulu angahlala kusixhumanisi esihamba kancane isikhathi esithile, abangele ukubambezeleka okukhulu ekulandeleni amaphakethe nokwandisa i-lag kanye ne-latency encane. Isibonelo, iphakethe le-1500 byte, elikhulu kunawo wonke avunyelwe i-Ethernet kusendlalelo senethiwekhi (yingakho iningi le-Intanethi), lingabopha imodemu eyi-14.4k cishe umzuzwana owodwa.
I-LLC: Ukulawulwa Kokuxhumanisa Okunengqondo
o Isendlalelo se-Logical Link Control (LLC) yedatha yokuxhumana kwedatha ungqimba olungaphezulu olungaphezulu lwe-Data Link Layer ebalulwe kumodeli we-OSI wezingqimba eziyisikhombisa (ungqimba 2). Inikeza izindlela zokulawula ukuphindaphindeka nokugeleza okwenza kube lula ukuthi izivumelwano eziningana zenethiwekhi (i-IP, i-IPX) zihlangane ngaphakathi kwenethiwekhi ye-multipoint futhi zithuthwe ngemidiya efanayo yenethiwekhi.
Isendlalelo esingaphansi se-LLC sisebenza njengesixhumi esibonakalayo phakathi kwesendlalelo esingaphansi seMedia Access Control (MAC) kanye nesendlalelo senethiwekhi. Kuyafana ngemidiya ehlukahlukene ebonakalayo (efana ne-Ethernet, indandatho yethokheni, ne-WLAN
Ozithobayo,
