Intshayelelo
Sonke siyayazi imigaqo yokwahlulahlula kunye nomgaqo wokungahluli we-IP kunye nokusetyenziswa kwayo kunxibelelwano lwenethiwekhi. Ukuqhekeka kunye nokuhlanganiswa kwakhona kwe-IP yindlela ebalulekileyo kwinkqubo yokudluliselwa kwepakethi. Xa ubungakanani bepakethi budlula umda weYunithi yokudluliselwa ephezulu (i-MTU) yekhonkco lenethiwekhi, ukuqhekeka kwe-IP kwahlula ipakethi ibe ziingceba ezininzi ezincinci zokudluliselwa. Ezi zingceba zidluliselwa ngokuzimeleyo kwinethiwekhi kwaye, xa zifika kwindawo eziya kuyo, zihlanganiswa kwakhona zibe ziipakethi ezipheleleyo ngendlela yokuhlanganiswa kwakhona kwe-IP. Le nkqubo yokuqhekeka kunye nokuhlanganiswa kwakhona iqinisekisa ukuba iipakethi ezinkulu zinokudluliselwa kwinethiwekhi ngelixa kuqinisekiswa ukuthembeka kunye nokuthembeka kwedatha. Kweli candelo, siza kujonga nzulu indlela ukusebenza kokuqhekeka kunye nokuhlanganiswa kwakhona kwe-IP.
Ukuqhekeka kwe-IP kunye nokuhlanganiswa kwakhona
Iikhonkco zedatha ezahlukeneyo zineeyunithi ezahlukeneyo zothumelo oluphezulu (i-MTU); umzekelo, ikhonkco ledatha le-FDDI line-MTU engama-4352 bytes kunye ne-Ethernet MTU engama-1500 bytes. I-MTU imele i-Maximum Transmission Unit kwaye ibhekisa kubungakanani obukhulu bepakethi obunokudluliselwa ngenethiwekhi.
I-FDDI (iFiber Distributed Data Interface) ngumgangatho wenethiwekhi yendawo (i-LAN) osebenzisa i-optical fiber njengendlela yokudlulisa idatha. I-Maximum Transmission Unit (MTU) yeyona sayizi iphezulu yepakethi enokudluliselwa ngeprotocol ye-data link layer. Kwiinethiwekhi ze-FDDI, ubungakanani be-MTU buyi-4352 bytes. Oku kuthetha ukuba ubukhulu bepakethi obuphezulu obunokudluliselwa ngeprotocol ye-data link layer kwinethiwekhi ye-FDDI yi-4352 bytes. Ukuba ipakethi eza kudluliselwa idlula obu bungakanani, kufuneka iqhekezwe ukuze yahlulwe ipakethi ibe ziingceba ezininzi ezifanelekileyo kubungakanani be-MTU bokudluliselwa kunye nokuhlanganiswa kwakhona kwi-receiver.
Kwi-Ethernet, i-MTU idla ngokuba yi-1500 bytes ngobukhulu. Oku kuthetha ukuba i-Ethernet inokudlulisa iipakethi ukuya kuthi ga kwi-1500 bytes ngobukhulu. Ukuba ubungakanani bepakethi budlula umda we-MTU, ipakethi iyahlulwahlulwa ibe ziingceba ezincinci ukuze idluliselwe kwaye ihlanganiswe kwakhona kwindawo ekuyiwa kuyo. Ukuhlanganisa kwakhona i-datagram ye-IP eqhekekileyo kunokwenziwa kuphela yi-host yendawo ekuyiwa kuyo, kwaye i-router ayizukwenza umsebenzi wokuhlanganisa kwakhona.
Sithethe nangamacandelo e-TCP ngaphambili, kodwa i-MSS imele ubukhulu beCandelo eliPhezulu, kwaye idlala indima ebalulekileyo kwiprotocol ye-TCP. I-MSS ibhekisa kubungakanani becandelo ledatha eliphezulu elivunyelweyo ukuthunyelwa kuqhagamshelo lwe-TCP. Ngokufanayo ne-MTU, i-MSS isetyenziselwa ukunciphisa ubungakanani beepakethi, kodwa yenza njalo kwi-transport layer, i-TCP protocol layer. Iprotocol ye-TCP idlulisela idatha yomaleko wesicelo ngokwahlula idatha kwiicandelo ezininzi zedatha, kwaye ubungakanani becandelo ngalinye ledatha bunqunyelwe yi-MSS.
I-MTU yekhonkco ngalinye ledatha yahlukile kuba uhlobo ngalunye olwahlukileyo lwekhonkco ledatha lusetyenziselwa iinjongo ezahlukeneyo. Ngokuxhomekeke kwinjongo yokusetyenziswa, ii-MTU ezahlukeneyo zinokubanjwa.
Masithi umthumeli ufuna ukuthumela i-datagram enkulu ye-4000 byte ukuze idluliselwe ngekhonkco le-Ethernet, ngoko ke i-datagram kufuneka yahlulwe ibe yi-datagram ezintathu ezincinci ukuze idluliselwe. Oku kungenxa yokuba ubungakanani be-datagram nganye encinci abunakudlula umda we-MTU, oyi-1500 bytes. Emva kokufumana i-datagram ezintathu ezincinci, umamkeli uyazihlanganisa kwakhona kwi-datagram yokuqala ye-4000 byte enkulu ngokusekelwe kwinani lolandelelwano kunye ne-offset ye-datagram nganye.
Kwitransmission eqhekekileyo, ukulahleka kwefragment kuya kuyisusa yonke idatha ye-IP. Ukuze kuthintelwe oku, i-TCP yazisa i-MSS, apho ukuqhekeka kwenziwa kwi-TCP layer endaweni ye-IP layer. Inzuzo yale ndlela kukuba i-TCP inolawulo oluchanekileyo kubungakanani becandelo ngalinye, nto leyo ethintela iingxaki ezinxulumene nokuqhekeka kwi-IP layer.
Kwi-UDP, sizama ukungathumeli ipakethi yedatha enkulu kune-MTU. Oku kungenxa yokuba i-UDP yiprotokholi yothutho engenanxibelelwano, engaboneleli ngokuthembeka kunye neendlela zokudlulisela kwakhona ezifana ne-TCP. Ukuba sithumela ipakethi yedatha ye-UDP enkulu kune-MTU, iya kuqhekeka lulwahlulo lwe-IP ukuze idluliselwe. Nje ukuba enye yeziqwenga ilahlekile, iprotokholi ye-UDP ayinakuphinda idluliselwe, nto leyo ebangela ukulahleka kwedatha. Ke ngoko, ukuze siqinisekise ukudluliselwa kwedatha okuthembekileyo, kufuneka sizame ukulawula ubungakanani beepakethi zedatha ze-UDP ngaphakathi kwe-MTU kwaye siphephe ukudluliselwa okuqhekekileyo.
Umthengisi wePakethi yeNethiwekhi yeMylinking ™ingakwazi ukuchonga ngokuzenzekelayo iintlobo ezahlukeneyo zeprotocol ye-tunnel VxLAN/NVGRE/IPoverIP/MPLS/GRE, njl.njl., inokufunyanwa ngokweprofayili yomsebenzisi ngokwemveliso yokuhamba kwe-tunnel yeempawu zangaphakathi okanye zangaphandle.
○ Iyakwazi ukubona iipakethi zeleyibhile ze-VLAN, QinQ, kunye ne-MPLS
○ Ndingayibona i-VLAN yangaphakathi neyangaphandle
○ Iipakethi ze-IPv4/IPv6 zinokuchongwa
○ Ingachonga iipakethi zetonela ze-VxLAN, NVGRE, GRE, IPoverIP, GENEVE, MPLS
○ Iipakethi ze-IP Fragmented zinokuchongwa (Ukuchongwa kwe-IP fragmentation okuxhasiweyo kunye nokuxhasa ukuhlanganiswa kwakhona kwe-IP fragmentation ukuze kuphunyezwe ukuhluzwa kweempawu ze-L4 kuzo zonke iipakethi ze-IP fragmentation. Sebenzisa umgaqo-nkqubo we-traffic output.)
Kutheni i-IP iqhekekile kwaye i-TCP iqhekekile?
Ekubeni kuthumelo lwenethiwekhi, umaleko we-IP uza kuqhekeza ipakethe yedatha ngokuzenzekelayo, nokuba umaleko we-TCP awuhluli idatha, ipakethe yedatha iza kuqhekeka ngokuzenzekelayo ngumaleko we-IP kwaye idluliselwe ngokuqhelekileyo. Kutheni ke ngoko i-TCP ifuna ukuqhekeka? Akuyonto igqithisileyo na leyo?
Masithi kukho ipakethi enkulu engahlulwanga kumaleko we-TCP kwaye ilahlekile xa ihanjiswa; i-TCP iya kuyithumela kwakhona, kodwa kuphela kwipakethi enkulu iyonke (nangona umaleko we-IP wahlulahlula idatha ibe ziipakethi ezincinci, nganye kuzo inobude be-MTU). Oku kungenxa yokuba umaleko we-IP awukhathali malunga nokudluliselwa kwedatha okuthembekileyo.
Ngamanye amazwi, kwikhonkco lothutho lomatshini ukuya kwinethiwekhi, ukuba umaleko wothutho uyayiqhekeza idatha, umaleko we-IP awuyiqhekezi. Ukuba ukuqhekezwa akwenziwa kumaleko wothutho, ukuqhekezwa kunokwenzeka kumaleko we-IP.
Ngamazwi alula, i-TCP yahlulahlula idatha ukuze umaleko we-IP ungasaqhekeki, kwaye xa kusenzeka ukudluliselwa kwakhona, kuphela iinxalenye ezincinci zedatha eziqhekekileyo ezidluliselwa kwakhona. Ngale ndlela, ukusebenza kakuhle kokudluliselwa kunye nokuthembeka kunokuphuculwa.
Ukuba i-TCP yahlukene, ingaba umaleko we-IP awuhlukananga?
Kwingxoxo engasentla, sikhankanye ukuba emva kokuqhekeka kwe-TCP kumthumeli, akukho kuqhekeka kwi-IP layer. Nangona kunjalo, kunokubakho ezinye izixhobo ze-network layer kulo lonke ikhonkco lothutho ezinokuba ne-maximum transmission unit (MTU) encinci kune-MTU kumthumeli. Ke ngoko, nangona ipakethi iqhekekile kumthumeli, iqhekekile kwakhona njengoko idlula kwi-IP layer yezi zixhobo. Ekugqibeleni, zonke iziqwenga ziya kuhlanganiswa kwi-receiver.
Ukuba singayichonga i-MTU encinci kwikhonkco lonke size sithumele idatha kuloo mgama, akukho kuqhekeka kuya kwenzeka nokuba idatha idluliselwa kweyiphi i-node. Le MTU incinci kwikhonkco lonke ibizwa ngokuba yi-path MTU (PMTU). Xa ipakethi ye-IP ifika kwi-router, ukuba i-MTU ye-router ingaphantsi kobude bepakethi kwaye iflegi ye-DF (Do not Fragment) isetelwe kwi-1, i-router ayizukukwazi ukuqhekeza ipakethi kwaye ingayilahla kuphela. Kule meko, i-router ivelisa umyalezo wempazamo we-ICMP (Internet Control Message Protocol) obizwa ngokuba yi-"Fragmentation Needed But DF Set." Lo myalezo wempazamo we-ICMP uza kuthunyelwa kwidilesi yomthombo enexabiso le-MTU le-router. Xa umthumeli efumana umyalezo wempazamo we-ICMP, inokulungisa ubungakanani bepakethi ngokusekelwe kwixabiso le-MTU ukuze kuthintelwe imeko yokuqhekeka engavumelekanga kwakhona.
Ukuqhekeka kwe-IP kuyimfuneko kwaye kufuneka kuthintelwe kumaleko we-IP, ingakumbi kwizixhobo eziphakathi kwikhonkco. Ke ngoko, kwi-IPv6, ukuqhekeka kweepakethi ze-IP zizixhobo eziphakathi akuvumelekanga, kwaye ukuqhekeka kungenziwa kuphela ekuqaleni nasekupheleni kwekhonkco.
Ukuqonda Okusisiseko kwe-IPv6
I-IPv6 yinguqulelo yesi-6 ye-Internet Protocol, elandela i-IPv4. I-IPv6 isebenzisa ubude bedilesi obuyi-128-bit, obunokubonelela ngeedilesi ze-IP ezingaphezulu kunobude bedilesi obuyi-32-bit ye-IPv4. Oku kungenxa yokuba indawo yedilesi ye-IPv4 iyaphela kancinci kancinci, ngelixa indawo yedilesi ye-IPv6 inkulu kakhulu kwaye inokuhlangabezana neemfuno ze-Intanethi yexesha elizayo.
Xa kuthethwa nge-IPv6, ukongeza kwindawo engaphezulu yedilesi, ikwazisa ukhuseleko olungcono kunye nokukhula, oko kuthetha ukuba i-IPv6 inokubonelela ngamava angcono enethiwekhi xa kuthelekiswa ne-IPv4.
Nangona i-IPv6 ibikho ixesha elide, ukusasazwa kwayo kwihlabathi liphela kusacotha. Oku kungenxa yokuba i-IPv6 kufuneka ihambelane nenethiwekhi ekhoyo ye-IPv4, efuna utshintsho kunye nokufuduka. Nangona kunjalo, ngenxa yokuphelelwa ngamandla kweedilesi ze-IPv4 kunye nemfuno ekhulayo ye-IPv6, ababoneleli beenkonzo ze-Intanethi abaninzi kunye nemibutho bayamkela i-IPv6 kancinci kancinci, kwaye kancinci kancinci baqonda ukusebenza kwe-IPv6 kunye ne-IPv4.
Isishwankathelo
Kule sahluko, sijonge nzulu indlela ukusebenza ngayo ukwahlulwahlulwa kwe-IP kunye nokuhlanganiswa kwakhona. Iikhonkco zedatha ezahlukeneyo zineyunithi yoThumelo oluPhezulu (i-MTU) eyahlukileyo. Xa ubungakanani bepakethi budlula umda we-MTU, ukwahlulwahlulwa kwe-IP kwahlula ipakethi ibe ziingceba ezininzi ezincinci zokudluliselwa, kwaye kuzihlanganise kwakhona zibe yipakethi epheleleyo ngendlela yokuhlanganiswa kwakhona kwe-IP emva kokufika kwindawo ekuyiwa kuyo. Injongo yokuqhekeka kwe-TCP kukwenza umaleko we-IP ungabi yiingceba, kwaye udlulise idatha encinci kuphela eqhekekileyo xa kusenzeka ukudluliselwa kwakhona, ukuze kuphuculwe ukusebenza kakuhle kokudluliselwa kunye nokuthembeka. Nangona kunjalo, kunokubakho ezinye izixhobo zomaleko wenethiwekhi kulo lonke ikhonkco lothutho ezine-MTU encinci kuneyomthumeli, ngoko ke ipakethi iya kuqhekeka kwakhona kumaleko we-IP wezi zixhobo. Ukuqhekeka kumaleko we-IP kufuneka kuthintelwe kangangoko kunokwenzeka, ingakumbi kwizixhobo eziphakathi kwikhonkco.
Ixesha lokuthumela: Agasti-07-2025
