Ithe ngqo
Iiswitshi ze-Ethernet ezithe ngqo zinokuqondwa njengeeswitshi ze-line matrix ezinemigca enqamlezileyo phakathi kwee-ports. Xa ipakethi yedatha ifunyenwe kwi-input port, i-packet header iyajongwa, idilesi yendawo ekuyiwa kuyo yepakethi ifunyenwe, itafile yokukhangela yangaphakathi eguquguqukayo iyaqalwa, kwaye i-output port ehambelanayo iyaguqulwa. Ipakethi yedatha iqhagamshelwe kwindawo yokungena kunye ne-output, kwaye ipakethi yedatha iqhagamshelwe ngqo kwi-port ehambelanayo ukuze kufezekiswe umsebenzi wokutshintsha. Ngenxa yokuba akufuneki igcinwe, ukulibaziseka kuncinci kakhulu kwaye ukutshintsha kukhawuleza kakhulu, nto leyo eyinzuzo yayo. Ingxaki kukuba ekubeni umxholo wepakethi yedatha ungagcinwa yi-Ethernet switch, akunakwenzeka ukujonga ukuba ipakethi yedatha edluliselweyo ayilunganga na, kwaye amandla okufumanisa iimpazamo awakwazi ukunikezelwa. Ngenxa yokuba akukho cache, ii-input/output ports zesantya ezahlukeneyo azinakuqhagamshelwa ngqo, kwaye kulula ukulahleka.
Gcina kwaye udlulisele phambili
Imo yokugcina kunye neyokudlulisela phambili yindlela yesicelo kwicandelo leenethiwekhi zekhompyutha. Iqala ngokugcina ipakethi yedatha yezibuko lokufaka, ize ijonge i-CRC (i-cyclic redundancy code verification), ikhuphe idilesi yendawo ekuyiwa kuyo yephakheji yedatha emva kokucubungula iphakheji yempazamo, ize iyiguqulele kwizibuko lokukhupha ukuthumela iphakheji ngetafile yokukhangela. Ngenxa yoku, ukulibaziseka kokugcinwa kunye nokudlulisela phambili ekucutshungulweni kwedatha kukhulu, oku kukusilela kwayo, kodwa inokuzibona ngokuchanekileyo iipakethi zedatha ezingena kwiswitshi kwaye iphucule kakhulu ukusebenza kwenethiwekhi. Okubaluleke ngakumbi kukuba inokuxhasa ukuguqulwa phakathi kweezibuko ezinesantya esahlukileyo kwaye igcine umsebenzi wokubambisana phakathi kweezibuko ezinesantya esiphezulu kunye neezibuko ezinesantya esiphantsi.
Ukwahlulwa kweqhekeza
Esi sisisombululo phakathi kwezimbini zokuqala. Sijonga ukuba ubude bepakethe yedatha buyanele na kwii-byte ezingama-64. Ukuba ingaphantsi kwee-byte ezingama-64, kuthetha ukuba yipakethe yobuxoki kwaye ipakethe iyalahlwa; ukuba ingaphezulu kwee-byte ezingama-64, ipakethe iyathunyelwa. Le ndlela ayiboneleli ngokuqinisekiswa kwedatha. Isantya sayo sokucubungula idatha sikhawuleza kunokugcina nokudlulisa, kodwa sicotha kunokudlulisa ngqo. Ukwazisa ukutshintsha kweswitshi yeHirschman.
Kwangaxeshanye, iswitshi yeHirschman inokudlulisa idatha phakathi kweeports ezininzi. I-port nganye inokuthathwa njengecandelo lenethiwekhi elizimeleyo (qaphela: icandelo lenethiwekhi elingeyo-IP), kwaye izixhobo zenethiwekhi eziqhagamshelwe kuyo zinokonwabela yonke i-bandwidth ngokuzimeleyo ngaphandle kokukhuphisana nezinye izixhobo. Xa i-node A ithumela idatha kwi-node D, i-node B inokuthumela idatha kwi-node C ngaxeshanye, kwaye zombini zine-bandwidth epheleleyo yenethiwekhi kwaye zinonxibelelwano lwazo olubonakalayo. Ukuba kusetyenziswa iswitshi ye-Ethernet ye-10Mbps, i-traffic iyonke yeswitshi ilingana ne-2x10Mbps=20Mbps. Xa kusetyenziswa i-HUB ekwabelwana ngayo ye-10Mbps, i-traffic iyonke ye-HUB ayizukudlula i-10Mbps.
Ngamafutshane,Utshintsho lweHirschmansisixhobo senethiwekhi esinokugqibezela umsebenzi wokufaka kunye nokuthumela iifreyimu zedatha ngokusekelwe ekuqaphelweni kweedilesi ze-MAC. Iswitshi yeHirschman ingafunda iidilesi ze-MAC kwaye izigcine kwitheyibhile yedilesi yangaphakathi, kwaye ifikelele ngqo kujoliswe kuyo ngokutshintsha okwethutyana phakathi komsunguli kunye nomkeli wefreyimu yedatha.
Ixesha leposi: Disemba-12-2024