Ncaj qha-los ntawm
Cov Ethernet switches ncaj qha tuaj yeem nkag siab tias yog cov kab matrix switches nrog cov kab sib tshuam ntawm cov chaw nres nkoj. Thaum pom cov ntaub ntawv pob ntawv ntawm qhov chaw nres nkoj nkag, lub taub hau pob ntawv raug kuaj xyuas, qhov chaw nyob ntawm pob ntawv tau txais, lub rooj tshawb nrhiav sab hauv pib, thiab qhov chaw tso zis sib xws raug hloov pauv. Cov ntaub ntawv pob ntawv txuas nrog ntawm qhov sib tshuam ntawm qhov nkag thiab qhov tso zis, thiab cov ntaub ntawv pob ntawv txuas ncaj qha rau qhov chaw nres nkoj sib xws kom ua tiav qhov kev hloov pauv. Vim tias nws tsis tas yuav khaws cia, qhov qeeb me me heev thiab qhov hloov pauv sai heev, uas yog nws qhov zoo. Qhov tsis zoo yog tias vim tias cov ntsiab lus ntawm cov ntaub ntawv pob ntawv tsis tau khaws cia los ntawm Ethernet switch, nws tsis tuaj yeem kuaj xyuas seb cov ntaub ntawv pob ntawv xa mus puas yog qhov tsis raug, thiab tsis tuaj yeem muab qhov muaj peev xwm nrhiav qhov yuam kev. Vim tias tsis muaj cache, cov chaw nres nkoj nkag / tso zis ntawm qhov ceev sib txawv tsis tuaj yeem txuas ncaj qha, thiab nws yooj yim poob.
Khaws cia thiab xa mus tom ntej
Hom khaws cia thiab xa mus tom ntej yog hom siv hauv kev sib txuas lus hauv computer. Nws xub khaws cov ntaub ntawv ntawm qhov chaw nkag, tom qab ntawd ua qhov kev kuaj xyuas CRC (cyclic redundancy code verification), rho tawm qhov chaw nyob ntawm cov ntaub ntawv tom qab ua tiav cov ntaub ntawv yuam kev, thiab hloov nws mus rau hauv qhov chaw tso zis kom xa cov ntaub ntawv los ntawm lub rooj tshawb nrhiav. Vim li no, qhov kev ncua sijhawm ntawm kev khaws cia thiab xa mus tom ntej hauv kev ua cov ntaub ntawv yog loj, uas yog nws qhov tsis zoo, tab sis nws tuaj yeem ntes cov ntaub ntawv nkag mus rau hauv qhov hloov pauv tsis raug thiab txhim kho kev ua haujlwm ntawm network. Qhov tseem ceeb tshaj plaws yog tias nws tuaj yeem txhawb kev hloov pauv ntawm cov chaw nres nkoj ntawm ntau qhov ceev thiab tswj kev ua haujlwm sib koom tes ntawm cov chaw nres nkoj ceev thiab cov chaw nres nkoj ceev qis.
Kev cais tawm ntawm cov khoom tawg
Qhov no yog ib qho kev daws teeb meem ntawm ob qho thawj zaug. Nws xyuas seb qhov ntev ntawm cov ntaub ntawv pob ntawv puas txaus rau 64 bytes. Yog tias nws tsawg dua 64 bytes, nws txhais tau tias nws yog pob ntawv cuav thiab pob ntawv raug pov tseg; yog tias nws loj dua 64 bytes, pob ntawv raug xa mus. Txoj kev no tsis muab kev txheeb xyuas cov ntaub ntawv. Nws qhov ceev ntawm kev ua cov ntaub ntawv yog sai dua li kev khaws cia thiab kev xa mus, tab sis qeeb dua li kev hla ncaj qha. Qhia txog kev hloov ntawm Hirschman hloov.
Tib lub sijhawm, Hirschman switch tuaj yeem xa cov ntaub ntawv ntawm ntau lub chaw nres nkoj. Txhua lub chaw nres nkoj tuaj yeem suav tias yog ib qho ntu ntawm lub network ywj pheej (ceeb toom: ntu tsis yog IP network), thiab cov khoom siv network txuas nrog nws tuaj yeem txaus siab rau tag nrho cov bandwidth ywj pheej yam tsis muaj kev sib tw nrog lwm cov khoom siv. Thaum node A xa cov ntaub ntawv mus rau node D, node B tuaj yeem xa cov ntaub ntawv mus rau node C tib lub sijhawm, thiab ob qho tib si muaj tag nrho cov bandwidth ntawm lub network thiab muaj lawv tus kheej kev sib txuas virtual. Yog tias siv 10Mbps Ethernet switch, tag nrho cov tsheb khiav ntawm lub switch yog sib npaug rau 2x10Mbps = 20Mbps. Thaum siv 10Mbps sib koom HUB, tag nrho cov tsheb khiav ntawm HUB yuav tsis pub tshaj 10Mbps.
Hauv luv luv, qhovHirschman hloovyog ib lub cuab yeej network uas tuaj yeem ua tiav qhov kev ua haujlwm ntawm kev kaw thiab xa cov ntaub ntawv raws li kev lees paub MAC chaw nyob. Lub Hirschman switch tuaj yeem kawm MAC chaw nyob thiab khaws cia rau hauv lub rooj chaw nyob sab hauv, thiab ncaj qha mus txog lub hom phiaj los ntawm kev hloov pauv ib ntus ntawm tus pib thiab tus txais ntawm lub hom phiaj ntawm cov ntaub ntawv.
Lub sijhawm tshaj tawm: Lub Kaum Ob Hlis-12-2024