Izendlalelo eziyisikhombisa zemodeli ye-OSI ziyisisekelo sokuqonda ukuthi amanethiwekhi okuxhumana anamuhla asebenza kanjani. Le modeli, eyasungulwa yi-International Organisation for Standardization (ISO), ihlukanisa umsebenzi oyinkimbinkimbi wokuxhumana kwenethiwekhi ibe yizendlalelo eziyisikhombisa ezihlukene, ngayinye inemithwalo yemfanelo ethile. Kusukela ekudluliseni izimpawu ezibonakalayo kuya ekuletheni izinsizakalo kuzinhlelo zokusebenza zomsebenzisi, isendlalelo ngasinye semodeli ye-OSI sidlala indima ebalulekile ekuqinisekiseni ukuthi idatha idluliselwa kahle nangokuthembekile kumanethiwekhi ahlukene. Kulo mhlahlandlela onemininingwane, sizohlola isendlalelo ngasinye kweziyisikhombisa zemodeli ye-OSI, sihlukanise imisebenzi yazo nokuthi zinegalelo kanjani ekusebenzeni okuphelele kwamanethiwekhi.
Izendlalelo ezingu-7 zemodeli ye-OSI: Qonda ileveli ngayinye ngale ncazelo enemininingwane
Imodeli ye-OSI namanethiwekhi ekhompyutha
Emhlabeni othokozisayo wamanethiwekhi wamakhompiyutha, kunomqondo owodwa obalulekile okufanele wonke uchwepheshe we-IT awubambe kahle: imodeli ye-OSI. Lolu hlaka lwethiyori, olwakhiwe yi-International Organisation for Standardization (ISO) ngo-1984, luyisisekelo sokuqonda ukuthi ukuxhumana kwenethiwekhi kusebenza kanjani. Izendlalelo eziyisi-7 zemodeli ye-OSI zihlinzeka ngesakhiwo esihlelekile esihlukanisa inqubo eyinkimbinkimbi yokudluliswa kwedatha ibe yizinyathelo ezilawulekayo neziqondakalayo.
Kodwa ayini amanethiwekhi wamakhompyutha ngempela? Empeleni, ayizinhlelo ezixhumene ezivumela ukushintshana kolwazi phakathi kwamadivayisi. Futhi imodeli ye-OSI iyikhampasi esiqondisa kule labyrinth eyinkimbinkimbi yokuxhumana nezivumelwano.
Kulesi sihloko, sizokwembula ungqimba ngalunye kwezingu-7 zemodeli ye-OSI, kusukela kungqimba yohlelo kuya kweyomzimba. Sizoqonda umsebenzi wabo ngamunye kanye nendlela abasebenzisana ngayo ukuze kuzuzwe ukuxhumana okubushelelezi nokusebenza kahle. Noma ngabe usaqala umsebenzi wakho wokuxhumana noma ufuna ukuthuthukisa amakhono akho, lo mhlahlandlela uzokunikeza ukuqonda okujulile, okusebenzayo kwemodeli ye-OSI.
Ulungele ukungena enhliziyweni yenethiwekhi yekhompyutha? Ake siqale uhambo lwethu ngokusebenzisa izendlalelo eziyisi-7 zemodeli ye-OSI!
Izendlalelo ezingu-7 zemodeli ye-OSI: Uhambo olusuka kuhlelo lokusebenza ukuya endaweni ebonakalayo
Imodeli ye-OSI (Open Systems Interconnection) ifana nemephu enemininingwane esiqondisa kunqubo eyinkimbinkimbi yokuxhumana kwenethiwekhi. Ingqimba ngayinye kweziyisikhombisa inomsebenzi othize nobalulekile. Ake sihlole ngayinye yazo, kusukela kosondelene kakhulu nomsebenzisi kuya kokuyisisekelo kakhulu.
Izendlalelo ezingu-7 zemodeli ye-OSI: Isendlalelo sesi-7 - Isicelo: Isixhumi esibonakalayo nomsebenzisi wokugcina
Isendlalelo sohlelo lokusebenza siseduze kakhulu nomsebenzisi wokugcina ngakho-ke sibonakala kakhulu. Yilapho izinhlelo esizisebenzisa nsuku zonke, njengeziphequluli zewebhu, amaklayenti e-imeyili nezinhlelo zokusebenza zemiyalezo esheshayo, zixhumana nenethiwekhi.
Lesi sendlalelo sihlinzeka ngamasevisi enethiwekhi ezinhlelweni zokusebenza futhi sichaza izivumelwano ezizisebenzisayo ukushintshanisa idatha. Amanye amaphrothokholi aziwa kakhulu asebenza kulesi sendlalelo yilawa:
- I-HTTP/HTTPS yokuphequlula iwebhu
- I-SMTP yokuthumela ama-imeyili
- I-FTP yokudlulisa ifayela
Isendlalelo sohlelo lokusebenza sibalulekile ngoba sinquma ukutholakala kwezinsiza zokuxhumana futhi sivumelanisa ukuxhumana phakathi kwezinhlelo zokusebenza. Ngaphandle kwayo, besingeke sikwazi ukufinyelela kumasevisi aku-inthanethi esiwathatha kalula ekuphileni kwethu kwansuku zonke kwedijithali.
Isibonelo, uma uvula isiphequluli sakho futhi uvakashela ikhasi lewebhu, isendlalelo sohlelo lokusebenza sisebenzisa umthetho olandelwayo we-HTTP ukucela nokwamukela idatha kuwebhusayithi. Lesi sendlalelo siphinde sibe nesibopho sokubonisa okuqukethwe ngendlela eqondakalayo kumsebenzisi, ukutolika i-HTML, CSS kanye nekhodi ye-JavaScript eyitholayo.
Kubalulekile ukuqaphela ukuthi ungqimba lohlelo lokusebenza alukhawulelwe kuzinhlelo zokusebenza zomsebenzisi wokugcina. Luhlanganisa nezinsizakalo kanye nezinqubo ezisetshenziswa izinhlelo zokusebenza kanye nezinhlelo zokusebenza zeseva, njenge-DNS yokulungiswa kwegama lesizinda noma i-SNMP yokuphathwa kwenethiwekhi.
Ngamafuphi, isendlalelo sohlelo lokusebenza yibhuloho phakathi komsebenzisi nenethiwekhi, elisiza ukusebenzisana namasevisi aku-inthanethi nokuqinisekisa ukuthi ulwazi lwethulwa ngendlela ewusizo nefinyelelekayo.
Izendlalelo eziyisi-7 zemodeli ye-OSI: Isendlalelo sesi-6 – Isethulo: Umhumushi Wedatha Wonke
Isendlalelo sokwethula, esaziwa nangokuthi isendlalelo se-syntax, sisebenza njengomhumushi ojwayelekile emhlabeni wamanethiwekhi ekhompyutha. Umsebenzi waso oyinhloko ukuqinisekisa ukuthi idatha ethunyelwe isendlalelo sohlelo olulodwa iyafundeka isendlalelo sohlelo olunye.
Lesi sendlalelo sinesibopho semisebenzi emithathu ebalulekile:
- Traducción: Iguqula idatha isuke kufomethi esetshenziswa uhlelo lokusebenza iye kufomethi yenethiwekhi evamile futhi ngokuphambene nalokho.
- Ukucindezela: Yehlisa usayizi wedatha ukuze kuthuthukiswe isivinini sokudlulisa.
- Ukubethela: Ivikela ulwazi olubucayi ngesikhathi sokudlulisela.
Isibonelo esicacile sokubaluleka kwesendlalelo sesethulo yilapho sithumela i-imeyili enefayela elinamathiselwe. Isendlalelo sephrezentheshini siqinisekisa ukuthi ifayela, kungakhathaliseki ukuthi ifomethi yalo yoqobo (njenge-.docx, .pdf, noma .jpg), ibhalwe ngekhodi ngendlela engasakazwa ngenethiwekhi bese ikhishwa ikhodi ngendlela efanele ohlelweni lokwamukela.
Ukwengeza, isendlalelo sokwethula siphatha ukuminyanisa idatha, okubalulekile ekusebenzeni kahle kwenethiwekhi. Cabanga ukuthumela isithombe esinokucaca okuphezulu nge-imeyili. Isendlalelo sephrezentheshini singaminyanisa lesi sithombe ukuze sinciphise usayizi waso, sisheshise ukudluliswa nokulondoloza umkhawulokudonsa, ngaphandle kokubeka engcupheni ikhwalithi yesithombe engozini.
Uma kuziwa ekuvikelekeni, isendlalelo sephrezentheshini sidlala indima ebalulekile. Uma wenza okwenziwa ku-inthanethi, isibonelo, lesi sendlalelo sinesibopho sokubethela idatha yakho yezezimali ngaphambi kokuthi ithunyelwe ngenethiwekhi, nokuyisusa lapho ifika lapho iya khona.
Kubalulekile ukuqaphela ukuthi nakuba imodeli ye-OSI ichaza ngokucacile isendlalelo sesethulo, ngokusebenza imisebenzi yayo eminingi ivame ukusetshenziswa kungqimba yohlelo lokusebenza kumamodeli enethiwekhi yesimanje. Kodwa-ke, ukuqonda indima yabo yethiyori kubalulekile ukuze ube nombono ophelele wokuthi amanethiwekhi amakhompyutha asebenza kanjani.
Izendlalelo eziyisi-7 zemodeli ye-OSI: Isendlalelo sesi-5 – Iseshini: Ukuhlela ukuxhumana phakathi kwezinhlelo zokusebenza
Isendlalelo seseshini, sesihlanu kumodeli ye-OSI, sisebenza njengomhleli wezingxoxo emhlabeni wedijithali. Umsebenzi wayo oyinhloko ukusungula, ukugcina nokunqamula izikhathi phakathi kwezinhlelo zokusebenza kumishini yokuxhumana.
Kodwa iyini ngempela iseshini kumongo wamanethiwekhi? Zicabange uxoxa ngocingo. Ucingo ngokwalo, ukusuka ekushayeni kuye ekuvaleni ucingo, lungalingana neseshini ngokwemibandela yenethiwekhi. Isendlalelo seseshini sinesibopho sokuqalisa lolu “cingo,” luyigcine lusebenza isikhathi eside njengoba kudingeka, futhi ekugcineni, luyivale ngendlela ehlelekile.
Izibopho ezibalulekile zesendlalelo seseshini zihlanganisa:
- Ukusungula iseshini: Iqala ukuxhumana phakathi kwezinhlelo zokusebenza.
- Ukugcinwa kweseshini: Iqinisekisa ukuthi ukuxhumana kuyaqhubeka ngaphandle kokuphazamiseka.
- Ukuvumelanisa: Ingeza izindawo zokuhlola kudatha ukuze ukudluliselwa kuqaliswe kabusha kusukela endaweni yokugcina uma kwenzeka kuba nokuphazamiseka.
- Ukunqanyulwa kweseshini: Ukukhulumisana okuseduze ngendlela ehlelekile lapho kungasadingeki.
Isibonelo esisebenzayo sesendlalelo seseshini esisebenzayo yilapho ubuka ividiyo esakazwayo. Isendlalelo seseshini sisungula uxhumano lokuqala kuseva yokusakaza, sigcina lolu xhumo luvuliwe ngenkathi ubuka ividiyo, futhi uma ngesizathu esithile uxhumano lwakho luphazamiseka okwesikhashana, luvumela ividiyo ukuthi iphinde iqale lapho igcine khona esikhundleni sokuthi iqale kusukela ekuqaleni.
Esinye isibonelo sansuku zonke iseshini yokubhanga ku-inthanethi. Uma ungena ku-akhawunti yakho yasebhange, isendlalelo seseshini sisungula ukuxhumana okuphephile phakathi kwedivayisi yakho neseva yebhange. Igcina le seshini isebenza ngenkathi wenza ukuthenga kwakho, futhi lapho uphuma noma ngemva kwesikhathi sokungasebenzi, isendlalelo seseshini sinakekela ukunqamula ukuxhumeka ngokuvikelekile.
Kubalulekile ukuqaphela ukuthi isendlalelo seseshini siphinde sisingathe isilawuli sengxoxo, sinquma ukuthi iyiphi inhlangano engadlulisela noma nini. Lokhu kubalulekile ezinhlelweni zesikhathi sangempela ezifana nenkomfa ngevidiyo, lapho kudingeka khona ukuxhumanisa ukuthi ubani okhulumayo nokuthi nini.
Ngamafuphi, isendlalelo seseshini sisebenza njengomqhubi, siqinisekisa ukuthi zonke "izingxoxo" kunethiwekhi ziyaqalwa, ziyagcinwa, futhi zivalwa ngendlela ehlelekile nephumelelayo. Indima yayo ibalulekile ekuqinisekiseni ulwazi lomsebenzisi olushelelayo kuzo zonke izinhlobo zezinhlelo zokusebenza zenethiwekhi.
Izendlalelo ezingu-7 zemodeli ye-OSI: Isendlalelo sesi-4 - Ezokuthutha: Ukuqinisekisa ukulethwa okuthembekile kwedatha
Isendlalelo sezokuthutha, sesine kumodeli ye-OSI, sifana nesevisi yokuthumela imiyalezo yamanethiwekhi ekhompyutha. Umsebenzi wayo oyinhloko ukuqinisekisa ukuthi idatha ilethwa ngendlela ephelele, ehlelekile futhi engenaphutha. Lesi sendlalelo sisebenza njengebhuloho phakathi kwezendlalelo eziphezulu ezigxile kuhlelo lokusebenza nezendlalelo ezingaphansi ezigxile kunethiwekhi.
Izibopho ezibalulekile zesendlalelo sezokuthutha zihlanganisa:
- Ukuhlukaniswa kanye nokuhlanganisa kabusha: Ihlukanisa idatha ibe amasegimenti amancane ukuze idluliselwe futhi ihlanganise kabusha endaweni okuyiwa kuyo.
- Ukulawula ukugeleza: Ilawula isivinini sokudlulisa ukuvimbela isidlulisi ukuthi singalayishi kakhulu isamukeli.
- Ukulawula iphutha: Ithola futhi ilungise amaphutha ekudluliseni.
- Ukulawula ukuminyana: Gwema ukugcwala kwenethiwekhi.
Amaphrothokholi amabili amakhulu asebenza kulesi sendlalelo yilawa:
- I-TCP (Transmission Control Protocol): Igxile ekuxhumekeni, iqinisekisa ukulethwa okuthembekile kwedatha.
- I-UDP (User Datagram Protocol): Ayiqondile ekuxhumekeni, ibeka phambili isivinini kunokwethenjelwa.
Ukuze uqonde kangcono ukuthi isendlalelo sezokuthutha sisebenza kanjani, ake sicabangele isibonelo sokuthumela i-imeyili enokunamathiselwe okukhulu. Isendlalelo sezokuthutha, sisebenzisa i-TCP, sizokwephula ifayela libe amasegimenti amancane. Ingxenye ngayinye ifakwe izinombolo ukuze kuqinisekiswe ukuthi ingahlanganiswa kabusha ngokulandelana kwayo endaweni. Uma noma iyiphi ingxenye ilahleka ngesikhathi sokudlulisela, i-TCP izonakekela ukucela ukudluliswa kwayo kabusha.
Ngakolunye uhlangothi, ocingweni lwezwi nge-inthanethi (VoIP), i-UDP ivamise ukusetshenziswa. Lapha, okubalulekile ukulethwa okusheshayo kwamaphakethe ezwi, ngisho noma lokho kusho ukulahlekelwa elilodwa ngezikhathi ezithile. Kungcono ukuba nokuphazamiseka okuncane kumsindo kunokubambezeleka okukhulu okubangelwa ukudluliswa kabusha kwamaphakethe alahlekile.
Isendlalelo sezokuthutha siphinde sidlale indima ebalulekile ekulawuleni izingxoxo eziningi ngasikhathi sinye. Isibonelo, uma unamathebhu amaningi avuliwe esipheqululini sakho, ngalinye lifinyelela iwebhusayithi ehlukile, isendlalelo sezokuthutha siqinisekisa ukuthi idatha evela kusayithi ngayinye ifika kuthebhu elungile.
Kubalulekile ukuqaphela ukuthi isendlalelo sezokuthutha yisendlalelo sokuqala esisebenza ekupheleni kuya ekupheleni, okungukuthi, kusukela kudivayisi yomthombo kuya kudivayisi yendawo. Izendlalelo ezingezansi zisebenza ngokuyinhloko phakathi kwamadivayisi aseduze kunethiwekhi.
Kafushane, ungqimba lwezokuthutha lubalulekile ekuqinisekiseni ukuxhumana okuthembekile nokusebenza kahle kumanethiwekhi amakhompyutha. Kungakhathaliseki ukuthi uthumela i-imeyili, usakaza ividiyo, noma ubamba iqhaza engqungqutheleni yevidiyo, isendlalelo sezokuthutha sisebenza ngokungakhathali ukuze siqinisekise ukuthi idatha yakho ifika lapho iya khona ngendlela efanele nangendlela efike ngesikhathi.
Izendlalelo eziyisi-7 zemodeli ye-OSI: Isendlalelo sesi-3 - Inethiwekhi: Amaphakethe omzila ngenethiwekhi yomhlaba wonke
Isendlalelo senethiwekhi, isendlalelo sesithathu kumodeli ye-OSI, sifana nesistimu yokuzula ye-GPS yamanethiwekhi ekhompyutha. Umsebenzi wayo oyinhloko ukunquma umzila ongcono kakhulu wamaphakethe wedatha ukuhamba ukusuka emthonjeni ukuya endaweni, ngokusebenzisa amanethiwekhi amaningi amaphakathi uma kudingeka.
Izibopho ezibalulekile zesendlalelo senethiwekhi zihlanganisa:
- Ukukhuluma okunengqondo: Inikeza amakheli e-IP kumadivayisi ukuze iwahlonze kunethiwekhi.
- umzila: Inquma umzila ongcono kakhulu wamaphakethe wedatha.
- Uqhekeko: Hlukanisa amaphakheji amakhulu abe amayunithi amancane uma kunesidingo.
- I-Congestion: Ilawula ithrafikhi yenethiwekhi ukuze igweme izinkinga.
Iphrothokholi eyaziwa kakhulu esebenza kulesi sendlalelo i-IP (Internet Protocol), eza ngezinguqulo ezimbili eziyinhloko: IPv4 kanye ne-IPv6.
Ukuze uqonde kangcono ukuthi ungqimba lwenethiwekhi lusebenza kanjani, ake sicabange ukuthi uthumela i-imeyili esuka ehhovisi lakho e-Madrid iya kosebenza naye e-Tokyo. Isendlalelo senethiwekhi kukhompyutha yakho sihlanganisa idatha ye-imeyili ibe amaphakethe e-IP, ngalinye linekheli lakho lasesizindeni se-inthanethi njengomthombo kanye nekheli le-IP lesiphakeli semeyili sozakwenu njengendawo oya kuyo.
Lawa maphakethe abe esehamba ngamarutha amaningi, ngalinye elihlola ikheli lendawo bese linquma ukuthi iphakethe lizolithumela kuphi ngokulandelayo. Kunjengokungathi umzila ngamunye uyiphoyisa lomgwaqo, eliqondisa amaphakethe endleleni ephumelela kakhulu eya lapho aya khona ekugcineni.
Isendlalelo senethiwekhi futhi sinesibopho sokuhlukaniswa kwephakethe nokuhlanganisa kabusha. Uma iphakethe likhulu kakhulu ukuthi lingasakazwa ngesixhumanisi esithile, isendlalelo senethiwekhi
d uyihlephule ibe yizingcezu ezincane. Isiqeshana ngasinye sihamba ngokuzimela kunethiwekhi, futhi uma zonke izingcezu sezifinyelele lapho kuthunyelwa khona, isendlalelo senethiwekhi kumamukeli siyawahlanganisa ukuze akhe kabusha iphakethe langempela.
Ngokungeziwe ekuhlukaniseni, isendlalelo senethiwekhi siphatha ukulawula ukuminyana ukuze kuvinjelwe ithrafikhi yenethiwekhi ukuthi ingaminyene kakhulu, okungase kubangele ukubambezeleka noma ukulahleka kwephakethe. Lokhu kwenziwa kusetshenziswa ama-algorithms alungisa izinga lokudluliswa kwedatha ngokusekelwe esimweni samanje senethiwekhi.
Ukuze sibone ngeso lengqondo yonke inqubo, ake sibuyele esibonelweni se-imeyili . Uma iphakethe selifikile kuma-router aphakathi, ngalinye lihlola ikheli lendawo eliya kuyo bese linquma indlela engcono kakhulu eya eTokyo. Uma esinye sezixhumanisi endleleni siminyene noma siphansi, i-router ingaqondisa kabusha iphakethe kwenye indlela ukuze igweme ukubambezeleka.
Isendlalelo senethiwekhi sibalulekile ekuqinisekiseni ukuthi idatha ifika ngempumelelo lapho iya khona, ngaphandle kokuhlukahluka okungenzeka kunethiwekhi. Ngaphandle kwesendlalelo senethiwekhi, bekungeke kube khona indlela ethembekile yokuletha idatha kuwo wonke amanethiwekhi amaningi, okwenza ukuxhumana kwesimanje okufana ne-imeyili, ukuphequlula iwebhu, nokushaya kwevidiyo kube nzima kakhulu.
Ngamafuphi, ungqimba lwenethiwekhi lubalulekile ekusebenzeni kwamanethiwekhi omhlaba ngokuphatha umzila, ikheli, ukuhlukana, nokulawula ukuminyana, ukuqinisekisa ukuthi idatha idluliswa kahle nangempumelelo isuka emthonjeni iye endaweni yokugcina.
Izendlalelo eziyisi-7 zemodeli ye-OSI: Isendlalelo sesi-2 – Isixhumanisi Sedatha: Ukuqinisekisa Ukuxhumana Kwasendaweni Kunethiwekhi
Isendlalelo sesixhumanisi sedatha, isendlalelo sesibili kumodeli ye-OSI, sinesibopho sokuhlinzeka ngokuxhumana okuthembekile phakathi kwamadivayisi amabili ngaphakathi kwenethiwekhi yendawo. Kucabange njengowengamele ukuqinisekisa ukuthi ukushintshisana kolwazi phakathi kwamakhompyutha kunethiwekhi efanayo kulungile futhi kuhlelekile.
Izibopho ezibalulekile zesendlalelo sesixhumanisi sedatha zihlanganisa:
- Ukukhuluma ngokomzimba: Isebenzisa amakheli e-MAC (Media Access Control) ukuze ihlonze ngokuhlukile idivayisi ngayinye kunethiwekhi yendawo.
- Ukulawula ukufinyelela kwemidiya: Ilawula ukufinyelela kusiteshi sokuxhumana ukuze igweme ukungqubuzana lapho amadivaysi amaningi ezama ukudlulisa idatha ngesikhathi esisodwa.
- Ukutholwa kwephutha nokulungiswa: Kufaka phakathi izindlela zokuthola nokulungisa amaphutha okungenzeka ngesikhathi sokudluliswa kwedatha.
Iphrothokholi eyaziwa kakhulu kulesi sendlalelo i-Ethernet, esetshenziswa kakhulu kuma-LAN. I-Ethernet ihlela idatha ibe ozimele futhi iqinisekisa ukuthi amadivayisi axhunywe kunethiwekhi efanayo angaxhumana kahle.
Ake sicabange ukuthi uthumela ifayela ngenethiwekhi ye-Wi-Fi ekhaya lakho. Isendlalelo sesixhumanisi sedatha kukhompuyutha yakho sithatha ifayela futhi sisihlephule sibe ozimele. Uhlaka ngalunye luhlanganisa ikheli le-MAC ledivayisi eyamukelayo kanye nekhodi yokuqinisekisa ukuthi uhlaka lufike ngaphandle kwamaphutha. Isendlalelo sesixhumanisi sedatha siphatha ukuxhumana okuqondile phakathi kwekhompyutha yakho nerutha, siqinisekisa ukuthi amafreyimu athunyelwa futhi amukelwe ngendlela efanele.
Izendlalelo eziyisi-7 zemodeli ye-OSI: Isendlalelo 1 - Okomzimba: Ukudlulisa idatha ngesimo samasignali
Isendlalelo esibonakalayo, esokuqala kumodeli ye-OSI, sibhekene nokudluliswa kwangempela kwedatha endaweni ebonakalayo yenethiwekhi. Lesi sendlalelo sinesibopho sokuguqula idatha ibe amasignali kagesi, optical noma omsakazo akwazi ukuhamba ngamakhebula, ama-optical fibers noma umoya.
Izibopho ezibalulekile zesendlalelo somzimba zihlanganisa:
- Ukudluliswa kwesignali: Ichaza izici zikagesi, i-optical and radio frequency yokuthumela nokwamukela idatha.
- Umbhalo Wekhodi Wedatha: Iguqula idatha yedijithali ibe amasiginali angadluliselwa endaweni ebonakalayo.
- Ukutholwa kwephutha elibonakalayo: Ihlonza futhi isingathe amaphutha angase avele ngenxa yezinkinga endaweni yokudlulisela, njengokuphazamiseka noma ukulahleka kwesignali.
Kulesi sendlalelo, izimiso namazinga ahlanganisa i-Ethernet (ngokwemibandela yezintambo nezixhumi), i-Wi-Fi (yamanethiwekhi angenantambo), kanye nokucaciswa kwe-fiber optic.
Uma sibuyela esibonelweni sefayela olithumela nge-Wi-Fi, isendlalelo esibonakalayo yiso esiphethe ukudluliswa kwangempela kwefayela. Ikhompyutha yakho iguqula idatha esefayelini ibe amasignali omsakazo athunyelwa kumzila. Umzila ube usuthola lawa masignali, uwaguqulele emuva kudatha yedijithali, bese izithumela ngenethiwekhi yendawo. Isendlalelo esibonakalayo siqinisekisa ukuthi lezi zimpawu zidluliselwa ngendlela efanele futhi ngaphandle kokulahlekelwa, ukuze idatha ifinyelele lapho iya khona.
Ngamafuphi, isendlalelo sesixhumanisi sedatha sigxile ekuxhumaneni ngaphakathi kwenethiwekhi yendawo, iqinisekisa ukudluliswa okuthembekile phakathi kwamadivayisi, kuyilapho isendlalelo esibonakalayo siphatha ukudluliswa kwangempela kwedatha kuyo yonke indawo ebonakalayo, siqinisekisa ukuthi amasignali athunyelwa futhi amukelwa ngendlela efanele. Ndawonye, lezi zendlalelo zinika amandla ukuxhumana okusebenzayo nokunembe ngaphakathi kwenethiwekhi.
Imibuzo Evame Ukubuzwa Ngezendlalelo Eziyisi-7 Zemodeli Ye-OSI
1. Iyini imodeli ye-OSI futhi kungani ibalulekile?
Imodeli ye-OSI (Open Systems Interconnection) iwuhlaka lomqondo olulinganisa imisebenzi yenethiwekhi yokuxhumana ibe yizingqimba eziyisikhombisa ezihlukene. Le modeli ibalulekile ngoba inikeza indlela ehlelekile yokuqonda nokuklama amanethiwekhi, okwenza kube lula ukusebenzisana phakathi kwezinhlelo ezahlukene nobuchwepheshe.
2. Yiziphi izingqimba eziyi-7 zemodeli ye-OSI?
Izendlalelo eziyisikhombisa zemodeli ye-OSI yilezi:
- Isendlalelo 1 - Esomzimba: Inesibopho sokudluliswa kwezimpawu ngokusebenzisa i-medium ebonakalayo (amakhebula, ama-optical fibers, njll.).
- Ungqimba 2 - Isixhumanisi sedatha: Inikeza ukuxhumana okuthembekile phakathi kwamadivayisi kunethiwekhi yendawo futhi iphathe ikheli lendawo kanye nokulawula ukufinyelela kwemidiya.
- Ungqimba 3 - Inethiwekhi: Inesibopho sokuthungatha amaphakethe ngamanethiwekhi aphakathi nendawo namakheli anengqondo (njengamakheli e-IP).
- Ungqimba 4 – Ezokuthutha: Iqinisekisa ukulethwa okulungile kwedatha phakathi kwamasistimu wokugcina futhi isingatha ukulawulwa kokugeleza nokulungiswa kwamaphutha.
- Iseshini 5 - Iseshini: Iphatha ukusungulwa, ukugcinwa, kanye nokunqanyulwa kwamaseshini phakathi kwezicelo.
- Isendlalelo sesi-6 – Isethulo: Inesibopho sokumelwa nokuguqulwa kwedatha, iqinisekisa ukuthi iyaqondakala ezinhlelweni zokusebenza.
- Isendlalelo sesi-7 - Isicelo: Ihlinzeka ngamasevisi enethiwekhi kuzinhlelo zokusebenza zomsebenzisi wokugcina njenge-imeyili, ukuphequlula iwebhu, nokudluliswa kwamafayela.
3. Imuphi umsebenzi owenziwa ungqimba lwenethiwekhi (Isendlalelo sesi-3) kumodeli ye-OSI?
Isendlalelo senethiwekhi sinesibopho sokuqondisa amaphakethe edatha ukusuka emthonjeni ukuya endaweni ekuyiwa kuyo kuwo wonke amanethiwekhi amaningi. Ukwengeza, iphatha amakheli anengqondo isebenzisa amakheli e-IP, yenza ukuhlukana kwamaphakethe amakhulu, futhi ilawule ukuminyana ukuze igweme ukuvinjelwa kwenethiwekhi.
4. Uyini umehluko phakathi kwekheli le-MAC nekheli le-IP?
Ikheli le-MAC (Media Access Control) ikheli lendawo eliyingqayizivele elinikezwe idivayisi ngayinye yenethiwekhi futhi lisetshenziselwa ukuxhumana ngaphakathi kwenethiwekhi yendawo (Isendlalelo sesi-2). Ikheli le-IP (Iphrothokholi Ye-inthanethi) yikheli elinengqondo elisetshenziselwa ukukhomba amadivayisi kunethiwekhi yomhlaba wonke noma exhumene (Usendlalelo 3) futhi livumela umzila wamaphakethe kuwo wonke amanethiwekhi ahlukene.
5. Kuyini ukuhlukaniswa kwephakethe futhi iphathwa kuluphi ungqimba lwemodeli ye-OSI?
Ukuhlukaniswa kwephakethe kuyinqubo yokuhlukanisa iphakethe ledatha elikhulu libe yizingcezu ezincane ukuze kube lula ukudluliswa kwalo ngamanethiwekhi anemikhawulo yosayizi wephakethe. Le nqubo isingathwa kusendlalelo senethiwekhi (Isendlalelo sesi-3), esinesibopho sokuhlanganisa kabusha izingcezu endaweni oya kuyo.
6. Ukudluliselwa kwedatha okuthembekile kuqinisekiswa kanjani kungqimba lwezokuthutha (Uhlaka 4)?
Isendlalelo sezokuthutha siqinisekisa ukudluliswa okuthembekile kwedatha kusetshenziswa izindlela ezinjengokuhlukaniswa kwedatha, ukulawula ukugeleza, nokulungiswa kwamaphutha. Iphrothokholi eyaziwa kulesi sendlalelo, i-TCP (I-Transmission Control Protocol), inikeza ukuxhumana okugxile ekuxhumekeni okuqinisekisa ukuthi idatha ifika ngendlela efanele nangendlela efanele.
7. Iyiphi indima edlalwa ungqimba lwesicelo (Isendlalelo sesi-7) kumodeli ye-OSI?
Isendlalelo sohlelo lokusebenza isendlalelo esisebenzisana ngokuqondile nezinhlelo zokusebenza zomsebenzisi wokugcina, sinikeza izinsizakalo zenethiwekhi njenge-imeyili, ukuphequlula iwebhu, nokudlulisa amafayela. Lesi sendlalelo siqinisekisa ukuthi izinhlelo zokusebenza zingathumela futhi zamukele idatha ngenethiwekhi ngendlela eqondakalayo kumsebenzisi.
8. Kwenzekani uma idivayisi ingalandeli imodeli ye-OSI?
Uma idivayisi ingalandeli imodeli ye-OSI, kungase kube nezinkinga zokusebenzisana nezokuxhumana kunethiwekhi. Imodeli ye-OSI ihlinzeka ngezinga elivamile elisiza ukuhlanganiswa kobuchwepheshe namasistimu ahlukene, ngakho ukunamathela kule modeli kusiza ukuqinisekisa ukuthi amadivayisi angakwazi ukuxhumana futhi ahlanganyele ngempumelelo.
9. Ngingakwazi ukuqhathanisa imodeli ye-OSI namanye amamodeli enethiwekhi?
Yebo, imodeli ye-OSI ingafaniswa namanye amamodeli enethiwekhi, njengemodeli ye-TCP/IP. Imodeli ye-TCP/IP yenziwe lula, inezendlalelo ezine eziyinhloko uma kuqhathaniswa neziyisikhombisa zemodeli ye-OSI. Nokho, womabili amamodeli abhekana nokuxhumana kwenethiwekhi ngendlela ehlelekile futhi anikeze isisekelo sokuklama nokuqonda amanethiwekhi.
10. Ngingalusebenzisa kanjani ulwazi lwemodeli ye-OSI ekuxazululeni izinkinga zenethiwekhi?
Ukuqonda imodeli ye-OSI kukuvumela ukuthi ukhombe ukuthi inkinga yenethiwekhi ingenzeka kusiphi isendlalelo. Isibonelo, uma kunezinkinga zokuxhuma, ungaphenya isendlalelo esibonakalayo. Uma idatha ingalethwanga ngendlela efanele, ungase ufune ukuhlola isendlalelo sezokuthutha. Lokhu kuqonda kukusiza ukuthi wenze ukuxilonga okunembe kakhudlwana futhi usebenzise izixazululo ezisebenza kahle kakhulu.
Isiphetho: Izendlalelo ezingu-7 zemodeli ye-OSI: Qonda izinga ngalinye ngale ncazelo enemininingwane
Imodeli ye-OSI, enezendlalelo zayo eziyisikhombisa ezihlukene, ihlinzeka ngohlaka oluhlelekile nolunemininingwane yokuqonda nokuklama amanethiwekhi okuxhumana. Isendlalelo ngasinye semodeli ye-OSI senza umsebenzi othile, kusukela ekudluliseleni amasiginali ngokomzimba kuya ekulethweni kwezinsizakalo zenethiwekhi kuya kuzinhlelo zokusebenza zabasebenzisi bokugcina.
Ake sibukeze kafushane izendlalelo eziyisikhombisa zemodeli ye-OSI: Isigaba 1 - Esingokoqobo - siphatha ukudluliswa kwedatha kuyo yonke indawo ebonakalayo, sisungula isisekelo sokuxhumana kwenethiwekhi. Isigaba 2 - Isixhumanisi Sedatha - siqinisekisa ukuxhumana okuthembekile phakathi kwamadivayisi ngaphakathi kwenethiwekhi yendawo, siphatha ikheli elingokoqobo kanye nokulawulwa kokufinyelela kwabezindaba. Isigaba 3 - Inethiwekhi - sinomthwalo wokuhambisa amaphakethe kumanethiwekhi amaningi, sisebenzisa amakheli e-IP ukuxhumana komhlaba wonke. Isigaba 4 - Ezokuthutha - siqinisekisa ukulethwa kwedatha okulungile nokuthembekile, ukuphatha ukulawula ukugeleza kanye nokulungiswa kwamaphutha. Isigaba 5 - Iseshini - sisiza ekusungulweni nasekugcinweni kokuxhumana phakathi kwezinhlelo zokusebenza. Isigaba 6 - Ukwethulwa - sihumusha futhi sifometha idatha ukuze iqondakale ngezinhlelo zokusebenza. Okokugcina, Isigaba 7 - Isicelo - sinikeza izinsizakalo eziqondile kuzinhlelo zokusebenza zabasebenzisi bokugcina, njenge-imeyili kanye nokuphequlula iwebhu.
Ukuqonda izendlalelo ezingu-7 zemodeli ye-OSI kubalulekile ekuxilongeni izinkinga zenethiwekhi, ukuklama izixazululo eziphumelelayo, nokuqinisekisa ukusebenzisana phakathi kobuchwepheshe obuhlukahlukene. Imodeli ye-OSI ihlinzeka ngolimi oluvamile olusiza ukusebenzisana phakathi kochwepheshe benethiwekhi nokuthuthukiswa kobuchwepheshe obusha. Ngalokhu kuqonda okuningiliziwe, ungasondela ekwakhiweni nasekuphathweni kwenethiwekhi ngombono ocacile nohlelekile, uthuthukise kokubili ukusebenza kahle nempumelelo ekuxhumaneni kwedatha.