Uluhlu ngalunye luchazwe
I-Interconnection ye-Intanethi yoVula (OSI)
Imodeli ye- Open Systems Interconnection (OSI) ichaza isakhelo sokunxibelelana ukuze kuphunyezwe iiprotoksi kwimiqolo, kunye nokulawula okudlulileyo ukusuka kwinqanaba elithile ukuya kwelinye elilandelayo. Kusetyenziswa ngokuyinhloko namhlanje njengethuluzi lokufundisa. Ikwahlula ngokucacileyo ulwahlulo lweekhompyutheni zecomputer zibe zi-7 kwiindawo ezihamba phambili. Iziqendu eziphantsi zijongene nempawu zombane, iinkcukacha zeenkcukacha zobuncinci kunye nokuhamba kwezi nkcukacha kwiinqununu. Amanqanaba aphakamileyo afaka izicelo zeenethwekhi kunye nezimpendulo, ukubonakaliswa kwedata, kunye neenkqubo zokunxibelelana kunye nenethiwekhi njengoko kubonwe kwinqanaba lomsebenzisi.
Imodeli ye-OSI yayikwakhelwe kuqala njengokwakhiwa komgangatho wendlela yokwakhiwa kwenethiwekhi kwaye ngokwenene, amaninzi amaninzi obuchwephesha beekhnoloji namhlanje abonakalisa i-OSI yoyilo.
01 ngo 07
Uluhlu lweZakhiwo
Kwisiqendu 1, umgca wePhysical of OSI model ujongene nokudluliselwa kokugqibela kwedatha yedatha yedijithali ukusuka kumgca wePhysical of the source (source) kwiinkonzo zonxibelelwano zenethiwekhi ukuya kwisakhiwo sePhysical of the reception (destination destination). Imizekelo yobuchwepheshe beTala 1 iquka i- Ethernet cables kunye nee- Token Ring amanethiwekhi . Ukongezelela, ii-hubs kunye nabanye abaphinda baphinda baphinde basebenzise amacebo enethiwekhi asemgangathweni asebenzayo kwinqanaba lePhysical, njengezixhobo zokuxhuma.
Kuloluhlu lwezinto eziphathekayo, idatha idluliselwa ngohlobo lokutshintshwa oluxhaswe ngumgangatho wesimo: iminyango yamagesi, ii-radio frequencies, okanye imitshini ye-infrared okanye ukukhanya okuqhelekileyo.
02 we-07
Ikhonkco leZixhobo zeDatha
Xa ufumana idatha esuka kumgca wePhysical, uluhlu lwe-Data Link luhlola iifayile zokudlulisela umzimba kunye neepakethi zithatha "kwiifom" zedatha. Uluhlu lwekhonkco lweDatha lulawula kwakhona iiplani zokulungisa iinjongo ezifana nee- MAC idilesi zeenethwekhi ze-Ethernet, ukulawula ukufikelela kwanoma yiyiphi iifayili zethungelwano ezihlukeneyo kumgangatho wenyama. Ngenxa yokuba ugcino lwe-Data Link lugqabileyo oluyinkimbinkimbi kunomzekelo we-OSI, luhlala luhlulwe zibe zimbini, i-"Media Access Control" kunye ne "Layical Link Control" sublayer.
03 we-07
Layer Network
Uluhlu lweNethwekhi longeza umgaqo wokuhamba ngaphaya kweLoqo loLwazi lweNgcaciso. Xa idatha ifika kwi-Uluhlu lweNethwekhi, iidilesi zendawo kunye neendawo ezikuyo zikhoyo ngaphakathi kwesakhelo ngasinye zihlolwe ukuba zichane ukuba i-data ifinyelele indawo yayo yokugqibela. Ukuba idatha ifinyelele kwindawo yokugqibela, le Nqwelwana 3 ifomatha idatha kwiipakethi ezinikezelwe kuluhlu lwezothutho. Ngaphandle koko, Uluhlu lweNethwekhi luhlaziya idilesi yokuya kwindawo kwaye luqhube isakhelo sehla kwiindawo eziphantsi.
Ukuxhasa uhambo, Uluhlu lweNethiwekhi lugcina iidilesi ezinengqiqo njengee- IP zamakheli ezixhobo kwi-intanethi. Uluhlu lweNethiwekhi lulawula kwakhona imephu phakathi kwezi dilesi ezinengqiqo kunye needesi zomzimba. Kwi-intanethi ye-IP, le mephu ifezekiswe kwi- Address Resolution Protocol (ARP) .
04 we-07
Umthamo wezothutho
Uluhlu lwezothutho luhambisa idatha kwiinkcukacha zonxibelelwano. I-TCP ngumzekelo oqhelekileyo weNkqubo yeThutho yoThutho lweThutho 4 . Iinkqubo ezahlukeneyo zothutho ziyakwazi ukuxhasa ubuninzi bezakhono ezikhethiweyo kuquka ukubuyiswa kwephutha, ukulawula ukuhamba, kunye nenkxaso yokudluliselwa kwakhona.
05 we-07
Uluhlu lweSession
I-Session Layer ilawula ukulandelelana kunye nokuhamba kweziganeko eziqalisa kunye nokudiliza intanethi. Kwisiqendu 5, sakhiwa ukuxhasa iintlobo ezininzi zonxibelelwano ezingadalwa ngokuzenzekelayo kwaye zigijime amanethiwekhi amaninzi.
06 we-07
Uluhlu lwentetho
Uluhlu lwesethulo lulula kakhulu kumsebenzi weliphi na iqela lomzekelo we-OSI. KuLuhlu lwe-6, lusetyenziswa ngokucwangciswa kwe-syntax yedatha yombhalo efana nokuguqulwa kwefomathi kunye nokubethela / ukuchithwa kwemfuneko okufunekayo ukuxhasa uluhlu lwesicelo ngaphezu kwalo.
07 we-07
Uludwe lwe sicelo
Uluhlu lwesicelo lunika iinkonzo zonxibelelwano kwizicelo zomsebenzisi wokuphela. Iinkonzo zenethiwekhi ziqhelekileyo iinkqubo ezisebenza kunye nedatha yomsebenzisi. Ngokomzekelo, kwisicelo sesiphequluli seWebhu, iipokethi ze- HTTP yekhowudi yokufaka isicelo idatha efunekayo ukuthumela nokufumana umxholo wephepha leWebhu. Le Layer 7 inikeza idatha kwi (kwaye ifumana idatha ukusuka) kwi-Layation layer.