Isingeniso
Sonke siyazi isimiso sokuhlukanisa kanye nesimiso sokungahlukanisi i-IP kanye nokusetshenziswa kwayo ekuxhumaneni kwenethiwekhi. Ukuhlukana kwe-IP kanye nokuhlanganiswa kabusha kuyindlela ebalulekile enqubweni yokudluliselwa kwephakethe. Lapho usayizi wephakethe udlula umkhawulo we-Maximum Transmission Unit (MTU) wesixhumanisi senethiwekhi, ukuhlukana kwe-IP kuhlukanisa iphakethe libe yizicucu eziningi ezincane zokudluliselwa. Lezi zicucu zidluliselwa ngokuzimela kunethiwekhi futhi, lapho zifika endaweni oya kuyo, zihlanganiswa kabusha zibe amaphakethe aphelele ngendlela yokuhlanganisa kabusha i-IP. Le nqubo yokuhlukana kanye nokuhlanganiswa kabusha iqinisekisa ukuthi amaphakethe amakhulu angadluliselwa kunethiwekhi ngenkathi kuqinisekiswa ubuqotho nokuthembeka kwedatha. Kulesi sigaba, sizobheka ngokujulile ukuthi ukuhlukana kanye nokuhlanganiswa kabusha kwe-IP kusebenza kanjani.
Ukuhlukaniswa kwe-IP kanye nokuhlanganiswa kabusha
Izixhumanisi zedatha ezahlukene zinamayunithi okudlulisa aphezulu ahlukene (i-MTU); isibonelo, isixhumanisi sedatha se-FDDI sine-MTU yama-byte angu-4352 kanye ne-Ethernet MTU yama-byte angu-1500. I-MTU imele i-Maximum Transmission Unit futhi ibhekisela kusayizi wephakethe omkhulu ongadluliselwa ngenethiwekhi.
I-FDDI (i-Fiber Distributed Data Interface) iyindinganiso yenethiwekhi yendawo (i-LAN) esheshayo esebenzisa i-optical fiber njengendlela yokudlulisa. I-Maximum Transmission Unit (MTU) iyindinganiso yephakethe ephezulu engadluliselwa ngephrothokholi yesendlalelo sesixhumanisi sedatha. Kumanethiwekhi e-FDDI, usayizi we-MTU ungama-byte angu-4352. Lokhu kusho ukuthi usayizi wephakethe ophezulu ongadluliselwa ngephrothokholi yesendlalelo sesixhumanisi sedatha kunethiwekhi ye-FDDI ungama-byte angu-4352. Uma iphakethe elizodluliselwa lidlula lo sayizi, lidinga ukuhlukaniswa ukuze lihlukanise iphakethe libe yizicucu eziningi ezifanele usayizi we-MTU wokudlulisa nokuhlanganisa kabusha kumamukeli.
Ku-Ethernet, i-MTU ngokuvamile ingama-byte angu-1500 ngobukhulu. Lokhu kusho ukuthi i-Ethernet ingadlulisela amaphakethe afinyelela ku-byte angu-1500 ngobukhulu. Uma usayizi wephakethe udlula umkhawulo we-MTU, khona-ke iphakethe lihlukaniswa libe yizingcezu ezincane ukuze lidluliselwe futhi lihlanganiswe kabusha endaweni oya kuyo. Ukuhlanganisa kabusha i-datagram ye-IP ehlukanisiwe kungenziwa kuphela yi-host yendawo oya kuyo, futhi i-router ngeke yenze umsebenzi wokuhlanganisa kabusha.
Siphinde sakhuluma ngezigaba ze-TCP ngaphambilini, kodwa i-MSS imele ubukhulu besigaba esiphezulu, futhi idlala indima ebalulekile kuphrothokholi ye-TCP. I-MSS ibhekisela kusayizi wesigaba sedatha esiphezulu esivunyelwe ukuthunyelwa kuxhumo lwe-TCP. Ngokufanayo ne-MTU, i-MSS isetshenziselwa ukukhawulela usayizi wamaphakethe, kodwa yenza kanjalo kungqimba lokuthutha, ungqimba lwephrothokholi ye-TCP. Iphrothokholi ye-TCP idlulisela idatha yengqimba yohlelo lokusebenza ngokuhlukanisa idatha ibe yizingxenye eziningi zedatha, futhi usayizi wengxenye ngayinye yedatha unqunyelwe yi-MSS.
I-MTU yesixhumanisi ngasinye sedatha ihlukile ngoba uhlobo ngalunye oluhlukile lwesixhumanisi sedatha lusetshenziselwa izinjongo ezahlukene. Kuye ngenhloso yokusetshenziswa, ama-MTU ahlukene angabanjwa.
Ake sithi umthumeli ufuna ukuthumela i-datagram enkulu engama-byte angu-4000 ukuze idluliselwe ngesixhumanisi se-Ethernet, ngakho-ke i-datagram idinga ukuhlukaniswa ibe ama-datagram amathathu amancane ukuze idluliselwe. Lokhu kungenxa yokuthi usayizi we-datagram ngayinye encane awukwazi ukudlula umkhawulo we-MTU, ongu-1500 bytes. Ngemva kokuthola ama-datagram amathathu amancane, umamukeli uwahlanganisa kabusha abe yi-datagram yokuqala enkulu engama-byte angu-4000 ngokusekelwe enombolweni yokulandelana kanye ne-offset ye-datagram ngayinye.
Ekudlulisweni okuqhekekile, ukulahleka kwengxenye kuzoyenza ingasebenzi yonke i-datagram ye-IP. Ukuze kugwenywe lokhu, i-TCP yethule i-MSS, lapho ukuqhekeka kwenziwa khona kungqimba lwe-TCP esikhundleni sengqimba ye-IP. Inzuzo yale ndlela ukuthi i-TCP inokulawula okunembe kakhulu ngobukhulu bengxenye ngayinye, okugwema izinkinga ezihambisana nokuqhekeka kungqimba lwe-IP.
Ku-UDP, sizama ukungathumeli iphakethe ledatha elikhulu kune-MTU. Lokhu kungenxa yokuthi i-UDP iyiphrothokholi yokuthutha engenakho ukuxhumana, enganikezi izindlela zokuthembeka nezokudlulisa kabusha njenge-TCP. Uma sithumela iphakethe ledatha le-UDP elikhulu kune-MTU, lizohlukaniswa ungqimba lwe-IP ukuze lidluliselwe. Uma enye yezingcezu ilahlekile, iphrothokholi ye-UDP ayikwazi ukudlulisa kabusha, okuholela ekulahlekelweni kwedatha. Ngakho-ke, ukuze siqinisekise ukudluliswa kwedatha okuthembekile, kufanele sizame ukulawula usayizi wamaphakethe edatha e-UDP ngaphakathi kwe-MTU futhi sigweme ukudluliswa okuqhekekile.
Umthengisi Wephakethe Lenethiwekhi ye-Mylinking ™Ingakwazi ukuhlonza ngokuzenzakalelayo izinhlobo ezahlukene zephrothokholi yomhubhe i-VxLAN/NVGRE/IPoverIP/MPLS/GRE, njll., inganqunywa ngokuya ngephrofayili yomsebenzisi ngokuya ngokuphuma kokugeleza komhubhe kwezici zangaphakathi noma zangaphandle.
○ Ingabona amaphakethe amalebula e-VLAN, QinQ, kanye ne-MPLS
○ Ingakwazi ukubona i-VLAN yangaphakathi neyangaphandle
○ Amaphakethe e-IPv4/IPv6 angabonakala
○ Ingakwazi ukubona amaphakethe e-VxLAN, NVGRE, GRE, IPoverIP, GENEVE, MPLS
○ Amaphakethe Ahlukaniswe yi-IP Angabonakala (Ukuhlonza ukuhlukaniswa kwe-IP okusekelwayo futhi kusekela ukuhlanganiswa kabusha kokuhlukaniswa kwe-IP ukuze kusetshenziswe ukuhlunga izici ze-L4 kuwo wonke amaphakethe okuhlukaniswa kwe-IP. Sebenzisa inqubomgomo yokukhipha ithrafikhi.)
Kungani i-IP iqhekekile futhi i-TCP iqhekekile?
Njengoba ekudlulisweni kwenethiwekhi, ungqimba lwe-IP luzohlukanisa ngokuzenzakalelayo iphakethe ledatha, noma ngabe ungqimba lwe-TCP lungahlukanisi idatha, iphakethe ledatha lizohlukaniswa ngokuzenzakalelayo ungqimba lwe-IP futhi lidluliselwe ngendlela evamile. Pho kungani i-TCP idinga ukuhlukaniswa? Akukhona yini lokho okweqile?
Ake sithi kukhona iphakethe elikhulu elingahlukaniswanga kungqimba ye-TCP futhi lilahleka ngesikhathi sokuthutha; i-TCP izolithumela kabusha, kodwa kuphela kulo lonke iphakethe elikhulu (yize ungqimba lwe-IP luhlukanisa idatha ibe amaphakethe amancane, ngalinye lawo linobude be-MTU). Lokhu kungenxa yokuthi ungqimba lwe-IP alunandaba nokudluliswa kwedatha okuthembekile.
Ngamanye amazwi, ekuthuthweni komshini kuya kusixhumanisi senethiwekhi, uma ungqimba lokuthutha luhlukanisa idatha, ungqimba lwe-IP aluyihlukanisi. Uma ukuhlukana kungenziwa kungqimba lokuthutha, ukuhlukana kungenzeka kungqimba lwe-IP.
Kalula nje, i-TCP ihlukanisa idatha ukuze ungqimba lwe-IP lungasahlukani, futhi lapho kuvela ukudluliselwa kabusha, izingxenye ezincane kuphela zedatha ezihlukanisiwe ezithunyelwa kabusha. Ngale ndlela, ukusebenza kahle kokudluliselwa kanye nokuthembeka kungathuthukiswa.
Uma i-TCP ihlukene, ingabe ungqimba lwe-IP aluhlukene?
Engxoxweni engenhla, sishilo ukuthi ngemva kokuqhekeka kwe-TCP kumthumeli, akukho ukuqhekeka kungqimba ye-IP. Kodwa-ke, kungase kube namanye amadivayisi engqimba yenethiwekhi kulo lonke isixhumanisi sokuthutha angaba neyunithi yokudlulisa ephezulu (i-MTU) encane kune-MTU kumthumeli. Ngakho-ke, noma ngabe iphakethe liqhekekile kumthumeli, liphinde liqhekeke njengoba lidlula kungqimba ye-IP yala madivayisi. Ekugcineni, wonke ama-shards azohlanganiswa kumamukeli.
Uma singanquma ubuncane be-MTU kuso sonke isixhumanisi bese sithumela idatha ngalobo bude, akukho ukuqhekeka okuzokwenzeka kungakhathaliseki ukuthi idatha idluliselwa kuyiphi i-node. Lobu buncane be-MTU kuso sonke isixhumanisi bubizwa ngokuthi indlela ye-MTU (PMTU). Uma iphakethe le-IP lifika ku-router, uma i-MTU ye-router ingaphansi kobude bephakethe futhi ifulegi le-DF (Do not Fragment) lisethwe ku-1, i-router ngeke ikwazi ukuqhekeka iphakethe futhi ingalilahla kuphela. Kulesi simo, i-router ikhiqiza umlayezo wephutha we-ICMP (Internet Control Message Protocol) obizwa ngokuthi "Ukuqhekeka Kuyadingeka Kodwa Kusethwe i-DF." Lo mlayezo wephutha le-ICMP uzothunyelwa emuva ekhelini lomthombo elinenani le-MTU le-router. Lapho umthumeli ethola umlayezo wephutha le-ICMP, angalungisa usayizi wephakethe ngokusekelwe enanini le-MTU ukuze agweme isimo sokuqhekeka esivinjelwe futhi.
Ukuqhekeka kwe-IP kuyadingeka futhi kufanele kugwenywe kusendlalelo se-IP, ikakhulukazi kumadivayisi aphakathi kusixhumanisi. Ngakho-ke, ku-IPv6, ukuqhekeka kwamaphakethe e-IP ngamadivayisi aphakathi kuye kwavinjelwa, futhi ukuqhekeka kungenziwa kuphela ekuqaleni nasekupheleni kwesixhumanisi.
Ukuqonda Okuyisisekelo kwe-IPv6
I-IPv6 inguqulo 6 ye-Internet Protocol, elandela i-IPv4. I-IPv6 isebenzisa ubude bekheli obuyi-128-bit, obunganikeza amakheli e-IP amaningi kunobude bekheli obuyi-32-bit be-IPv4. Lokhu kungenxa yokuthi isikhala sekheli le-IPv4 siyaphela kancane kancane, kuyilapho isikhala sekheli le-IPv6 sikhulu kakhulu futhi singahlangabezana nezidingo ze-inthanethi yesikhathi esizayo.
Uma kukhulunywa nge-IPv6, ngaphezu kwesikhala sekheli esengeziwe, kuletha nokuvikeleka okungcono kanye nokukhula, okusho ukuthi i-IPv6 inganikeza ulwazi olungcono lwenethiwekhi uma kuqhathaniswa ne-IPv4.
Nakuba i-IPv6 isikhona isikhathi eside, ukuthunyelwa kwayo emhlabeni wonke kusahamba kancane. Lokhu kungenxa yokuthi i-IPv6 idinga ukuhambisana nenethiwekhi ye-IPv4 ekhona, edinga ukuguquka nokufuduka. Kodwa-ke, njengoba amakheli e-IPv4 ephela kanye nesidingo esikhulayo se-IPv6, abahlinzeki bezinsizakalo ze-inthanethi abaningi nezinhlangano bamukela kancane kancane i-IPv6, futhi kancane kancane baqaphela ukusebenza kwe-IPv6 ne-IPv4 okunezitaki ezimbili.
Isifinyezo
Kulesi sahluko, sibheke ngokujulile ukuthi ukuhlukaniswa kwe-IP nokuhlanganiswa kabusha kusebenza kanjani. Izixhumanisi zedatha ezahlukene zine-Maximum Transmission Unit (MTU) ehlukile. Uma usayizi wephakethe udlula umkhawulo we-MTU, ukuhlukaniswa kwe-IP kuhlukanisa iphakethe libe yizingcezu eziningi ezincane zokudluliselwa, bese zihlanganiswa kabusha zibe yiphakethe eliphelele ngendlela yokuhlanganiswa kabusha kwe-IP ngemva kokufika endaweni oya kuyo. Inhloso yokuhlukaniswa kwe-TCP ukwenza ungqimba lwe-IP lungasabi yizingcezu, futhi kudluliselwe kabusha idatha encane ehlukanisiwe lapho kudluliselwa kabusha, ukuze kuthuthukiswe ukusebenza kahle kokudluliselwa nokuthembeka. Kodwa-ke, kungase kube namanye amadivayisi engqimba yenethiwekhi kulo lonke isixhumanisi sokuthutha i-MTU yayo engaba yincane kuneyomthumeli, ngakho-ke iphakethe lizophinde lihlukaniswe futhi kungqimba lwe-IP lwala madivayisi. Ukuhlukaniswa kungqimba lwe-IP kufanele kugwenywe ngangokunokwenzeka, ikakhulukazi kumadivayisi aphakathi kusixhumanisi.
Isikhathi sokuthunyelwe: Agasti-07-2025
