Cov kev lag luam network khiav lag luam yog nyob ntawm Layer 2 ntawm OSI cov qauv thaum cov kev khiav hauj lwm hauv kev khiav lag luam nyob hauv Layer 3. Qhov no feem ntau ua rau tsis meej pem lub ntsiab lus thiab lub hom phiaj ntawm lub Layer 3 hloov (tseem hu ua tus hloov kev hloov multilayer).
Ib qho Layer 3 hloov yog ib qho khoom siv khoos phis tshwj xeeb uas siv hauv kev sib koom tes. Layer 3 keyboards technically muaj ntau nyob rau hauv ntau nrog ib txwm routers, thiab tsis yog nyob rau hauv lub cev tsos. Ob leeg tuaj yeem pab txhawb tib qho kev sib txuas lus , tshawb xyuas cov khoom ntim khoom thiab ua qhov kev txiav txim siab mus raws li qhov chaw thiab qhov chaw nyob.
Ib qho ntawm qhov zoo ntawm ib txoj kab 3 hloov dua ib lub router yog nyob rau hauv txoj kev rov txiav txim siab. Txheej 3 keyboards yuav tsis tshua muaj kev tsis pom latency network vim cov ntawv ntim tsis tas yuav ua cov kauj ruam ntxiv los ntawm lub router.
Lub Hom Phiaj 3 Hloov
Txheej 3 keyboards tau xeeb ua ib lub tshuab los txhim kho cov kev ua haujlwm hauv kev ua haujlwm hauv zos loj hauv zos (LANs) zoo ib yam li cov neeg sab nraud .
Qhov tseem ceeb sib txawv ntawm txheej 3 keyboards thiab routers lus dag hauv kev kho vajtse internals. Kev kho vaj tse hauv ib txheej Layer 3 hloov cov khoom siv ntawm cov khoom siv thiab cov routers, hloov qee qhov router software logic nrog kev kho vaj tse kho vajtse kom muaj kev ua haujlwm zoo dua rau cov kev sib txuas lus hauv zos.
Tsis tas li ntawd, tau tsim los siv rau ntawm intranets, ib txheej Layer 3 yuav feem ntau tsis muaj nrog cov chaw nres nkoj WAN thiab network cheeb tsam nta ib tus qauv router yuav ib txwm muaj.
Cov keyboards no feem ntau yog siv los txhawb kev sib tw ntawm virtual LANs (VLANs). Cov Nyiaj Pab ntawm Cov Txheej 3 cov kauj vab los rau VLAN yog:
- Txo qhov nyiaj ntawm kev tshaj tawm hauv xov tooj
- Yooj yim tswj kev ruaj ntseg
- Txhim kho kev txhaum kev txhim kho
Li Cas 3 Hloov Cov Haujlwm
Ib txwm hloov dynamically tseem khiav tsheb ntawm nws tus kheej lub cev ports raws li lub chaw nyob lub cev ( MAC chaw nyob ) ntawm cov khoom siv txuas. Txheej 3 keyboards siv cov peev txheej no thaum tswj kev tsav tsheb hauv LAN.
Lawv kuj nthuav rau qhov no los ntawm kev siv IP chaw nyob cov ntaub ntawv los txiav txim siab thaum tswj kev khiav tsheb ntawm LANs. Hauv kev sib piv, Layer 4 keyboards tseem siv cov npav TCP los yog UDP chaw nres nkoj .
Siv Ib Layer 3 Hloov Nrog VLANs
Txhua tus virtual LAN yuav tsum muab nkag thiab chaw nres nkoj ntawm qhov pib hloov. Routing tsis rau txhua tus VLAN interface yuav tsum tau teev.
Qee txheej 3 keyboards siv DHCP kev txhawb nqa uas siv tau los cob kom tau tus IP chaw nyob rau hauv VLAN. Xwb, tus sab nraud DHCP tus neeg siv yuav tsum siv, los yog IP chaw nyob sib cais.
Cov teeb meem nrog cov txheej txheem 3 Hloov
Txheej 3 keyboards cov nqi ntau tshaj cov txwm keyboards, tiam sis tsawg tshaj cov caij routers. Configuring thiab tswj cov keyboards thiab VLANs kuj xav tau kev pab ntxiv.
Cov kev siv ntawm txheej 3 cov keyboards tsuas yog siv rau cov kev sib tshuam intranet nrog ib qho loj txaus ntawm cov khoom siv hluav taws xob thiab cov tsheb. Tsev tes hauj lwm feem ntau tsis muaj kev siv rau cov cuab yeej no. Lacking WAN functionality, Txheej 3 keyboards tsis yog hloov rau routers.
Lub npe ntawm cov keyboards no yog los ntawm cov ntsiab lus hauv OSI qauv, qhov txheej txheem 3 yog hu ua Network Layer. Hmoov tsis, qhov qauv ntawm theoretical tsis ua qhov txawv qhov sib txawv ntawm cov khoom lag luam. Lub npe tau tshwm sim los ntawm ntau qhov kev kub ntxhov nyob rau hauv kev lag luam.