Kupu Whakataki
E mōhio ana tātou katoa ki te kaupapa o te whakarōpūtanga me te kore whakarōpūtanga o te IP me tōna whakamahinga i roto i te whakawhitiwhitinga whatunga. Ko te wehewehenga me te whakakotahitanga anō o te IP he tikanga matua i roto i te tukanga tuku mōkihi. Ina nui ake te rahi o te mōkihi i te rohenga mōrahi o te Waehere Tuku (MTU) o te hononga whatunga, ka wehea e te wehewehenga IP te mōkihi kia maha ngā wāhanga iti hei tuku. Ka tukuna motuhaketia ēnei wāhanga i roto i te whatunga, ā, i te taenga ki te ūnga, ka huihuia anō kia oti ngā mōkihi mā te tikanga whakakotahitanga IP. Mā tēnei tukanga wehewehenga me te whakakotahitanga anō ka taea te tuku i ngā mōkihi rahi nui i roto i te whatunga, me te whakarite hoki i te pono me te pono o ngā raraunga. I tēnei wāhanga, ka tirohia hohonutia e tātou te mahi a te wehewehenga me te whakakotahitanga anō o te IP.
Te Wehewehenga me te Whakahuihui Anō i te IP
He rerekē ngā waeine tuku mōrahi (MTU) o ngā hononga raraunga rerekē; hei tauira, ko te MTU o te hononga raraunga FDDI he 4352 paita, ko te MTU Ethernet he 1500 paita. Ko te MTU he tohu mō te Maximum Transmission Unit, ā, e pā ana ki te rahi mōkihi mōrahi ka taea te tuku mā te whatunga.
Ko te FDDI (Fiber Distributed Data Interface) he paerewa whatunga rohe tere-teitei (LAN) e whakamahi ana i te muka whatu hei reo tuku. Ko te Maximum Transmission Unit (MTU) te rahi mōrahi o te mōkihi ka taea te tuku e te kawa paparanga hononga raraunga. I roto i ngā whatunga FDDI, ko te rahi o te MTU he 4352 paita. Ko te tikanga ko te rahi mōrahi o te mōkihi ka taea te tuku e te kawa paparanga hononga raraunga i roto i te whatunga FDDI he 4352 paita. Mena ka nui ake te mōkihi hei tuku i tēnei rahi, me wehewehe kia wehea te mōkihi kia maha ngā wāhanga e tika ana mō te rahi MTU mō te tuku me te whakakotahi anō i te kaiwhiwhi.
Mō te Ethernet, ko te rahi o te MTU he 1500 paita te nuinga. Ko te tikanga ka taea e Ethernet te tuku i ngā mōkihi tae atu ki te 1500 paita te rahi. Mena ka nui ake te rahi o te mōkihi i te rohe MTU, ka wehewehea te mōkihi ki ngā wāhanga iti ake hei tuku, ā, ka huihuia anō ki te ūnga. Ka taea anake te mahi huihui anō i te raraunga IP pakaru e te kaihautū ūnga, ā, kāore te pouara e mahi i te mahi huihui anō.
I kōrero anō tātou mō ngā wāhanga TCP i mua ake nei, engari ko te MSS te tikanga mō te Rahi Wāhanga Mōrahi, ā, he mahi nui tāna i roto i te kawa TCP. Ko te MSS e pā ana ki te rahi o te wāhanga raraunga mōrahi e whakaaetia ana kia tukuna i roto i te hononga TCP. He rite ki te MTU, ka whakamahia te MSS hei whakawhāiti i te rahi o ngā mōkihi, engari ka pērā i te paparanga kawe, te paparanga kawa TCP. Ka tukuna e te kawa TCP ngā raraunga o te paparanga tono mā te wehewehe i ngā raraunga ki ngā wāhanga raraunga maha, ā, ka whakawhāitihia te rahi o ia wāhanga raraunga e te MSS.
He rerekē te MTU o ia hononga raraunga nā te mea he rerekē ngā kaupapa e whakamahia ana mō ia momo hononga raraunga. I runga anō i te kaupapa whakamahi, ka taea te manaaki i ngā MTU rerekē.
Mehemea kei te hiahia te kaituku ki te tuku i tētahi raraunga nui 4000 paita hei tuku mā te hononga Ethernet, me wehe te raraunga kia toru ngā raraunga iti ake hei tuku. Nā te mea kāore e taea e te rahi o ia raraunga iti te neke ake i te rohe MTU, arā, 1500 paita. I muri i te whiwhinga o ngā raraunga iti e toru, ka huihui anō te kaiwhiwhi ki roto i te raraunga nui taketake 4000 paita i runga i te tau raupapa me te tauwehenga o ia raraunga.
I roto i te tuku raraunga pakaru, ka whakakorengia te raraunga IP katoa e te ngaronga o tētahi wāhanga. Hei karo i tēnei, i whakaurua mai e TCP te MSS, arā, ka mahia te wehewehenga i te paparanga TCP kaua e te paparanga IP. Ko te painga o tēnei huarahi he nui ake te mana whakahaere tika a TCP mō te rahi o ia wāhanga, e karo ana i ngā raruraru e pā ana ki te wehewehenga i te paparanga IP.
Mō te UDP, ka ngana mātou kia kaua e tuku i tētahi mōkihi raraunga nui atu i te MTU. Nā te mea he kawa kawe hononga kore a UDP, kāore e whakarato i ngā tikanga pono me te tuku anō pērā i te TCP. Mēnā ka tukuna e mātou he mōkihi raraunga UDP nui atu i te MTU, ka wāwāhia e te paparanga IP mō te tuku. Kia ngaro tētahi o ngā kongakonga, kāore e taea e te kawa UDP te tuku anō, ka ngaro ngā raraunga. Nō reira, kia tika ai te tuku raraunga, me ngana mātou ki te whakahaere i te rahi o ngā mōkihi raraunga UDP i roto i te MTU, me te karo i te tuku pakaru.
Kaihoko Mōkihi Whatunga Mylinking ™Ka taea te tautuhi aunoa i ngā momo kawa kauhanga VxLAN/NVGRE/IPoverIP/MPLS/GRE, me ētahi atu, ka taea te whakatau kia rite ki te kōtaha kaiwhakamahi e ai ki ngā āhuatanga o roto, o waho rānei o te putanga rere o te kauhanga.
○ Ka taea e ia te kite i ngā mōkihi tapanga VLAN, QinQ, me MPLS
○ Ka taea te tautuhi i te VLAN o roto, o waho hoki
○ Ka taea te tautuhi i ngā mōkihi IPv4/IPv6
○ Ka taea te tautuhi i ngā mōkihi kauhanga VxLAN, NVGRE, GRE, IPoverIP, GENEVE, MPLS
○ Ka taea te Tāutu i ngā Mōkihi Wehewehe IP (Ka tautokona te tautuhi wehewehe IP me te tautoko i te whakakotahitanga anō o te wehewehe IP kia taea ai te whakatinana i te tātari āhuatanga L4 ki ngā mōkihi wehewehe IP katoa. Whakatinanahia te kaupapa here putanga waka.)
He aha i wehewehea ai te IP, ā, i wehewehea ai te TCP?
I te mea i roto i te tuku whatunga, ka wāwāhi aunoa te paparanga IP i te mōkihi raraunga, ahakoa kāore te paparanga TCP e wāwāhi i ngā raraunga, ka wāwāhi aunoa te mōkihi raraunga e te paparanga IP, ā, ka tukuna noa. Nō reira, he aha te take e hiahiatia ai te wāwāhi i te TCP? Kāore ianei i te nui rawa?
Mehemea he mōkihi nui kāore i wehea i te paparanga TCP, ā, ka ngaro i te wā e tukuna ana; ka tukuna anō e te TCP, engari i roto i te mōkihi nui katoa anake (ahakoa ka wehea e te paparanga IP ngā raraunga ki ngā mōkihi iti ake, he roa MTU ia mō ia mōkihi). Nā te mea kāore te paparanga IP e aro ki te tuku raraunga pono.
Arā, i te hononga kawe a te mīhini ki te whatunga, ki te wāwāhia ngā raraunga e te paparanga kawe, e kore te paparanga IP e wāwāhia. Ki te kore e mahia te wāwāhi i te paparanga kawe, ka taea te wāwāhi i te paparanga IP.
I roto i ngā kupu māmā noa iho, ka wehewehea ngā raraunga e te TCP kia kore ai e pakaru te paparanga IP, ā, ina tukuna anōtia, he iti noa iho ngā wāhanga o ngā raraunga kua pakaru ka tukuna anōtia. Mā tēnei, ka taea te whakapai ake i te pai me te pono o te tuku.
Mena kua pakaru te TCP, kāore i pakaru te paparanga IP?
I roto i te kōrero i runga ake nei, i kōrero mātou i muri i te wehewehenga o te TCP i te kaituku, kāore he wehewehenga i te paparanga IP. Heoi, tera pea ētahi atu taputapu paparanga whatunga puta noa i te hononga kawe he iti ake te wae tuku mōrahi (MTU) i te MTU i te kaituku. Nō reira, ahakoa kua wehewehea te mōkihi i te kaituku, ka wehewehea anō i a ia e haere ana i roto i te paparanga IP o ēnei taputapu. Ā tōna wā, ka huihuia ngā maramara katoa ki te kaiwhiwhi.
Mena ka taea e tātou te whakatau i te MTU iti rawa mō te hononga katoa, ā, ka tukuna ngā raraunga i taua roa, kāore he wehewehenga e puta ahakoa ko tēhea pūnga ka tukuna ngā raraunga. Ko tēnei MTU iti rawa mō te hononga katoa ka kiia ko te ara MTU (PMTU). Ina tae mai he mōkihi IP ki tētahi pouara, mena he iti iho te MTU o te pouara i te roa o te mōkihi, ā, kua whakatakotoria te haki DF (Kaua e Wehewehea) ki te 1, kāore e taea e te pouara te wehewehe i te mōkihi, ā, ka taea noa e ia te whakataka. I tēnei wā, ka whakaputa te pouara i tētahi karere hapa ICMP (Internet Control Message Protocol) e kiia nei ko "Fragmentation Needed But DF Set." Ka tukuna atu tēnei karere hapa ICMP ki te wāhitau pūtake me te uara MTU o te pouara. Ina whiwhi te kaituku i te karere hapa ICMP, ka taea e ia te whakarerekē i te rahi o te mōkihi i runga i te uara MTU kia kore ai e puta anō te āhuatanga wehewehenga kua rāhuitia.
He mea nui te wehewehe i ngā IP, ā, me karo i te paparanga IP, inā koa i ngā taputapu takawaenga i roto i te hononga. Nō reira, i roto i te IPv6, kua rāhuitia te wehewehe i ngā mōkihi IP e ngā taputapu takawaenga, ā, ka taea anake te wehewehe i te tīmatanga me te mutunga o te hononga.
Te Māramatanga Taketake o te IPv6
Ko IPv6 te putanga 6 o te Internet Protocol, koinei te uri o IPv4. E whakamahi ana a IPv6 i te roanga wāhitau 128-moka, ka taea e tēnei te whakarato i ngā wāhitau IP maha atu i te roanga wāhitau 32-moka o IPv4. Nā te mea ka pau haere te wāhi wāhitau IPv4, engari he nui rawa te wāhi wāhitau IPv6, ā, ka taea e ia te whakatutuki i ngā hiahia o te Ipurangi ā muri ake nei.
Ina kōrerohia te IPv6, hei tāpiri atu ki te nui ake o te wāhi wāhitau, ka puta mai hoki he haumarutanga me te tauine pai ake, ko te tikanga ka taea e te IPv6 te whakarato i tētahi wheako whatunga pai ake i te IPv4.
Ahakoa kua roa te IPv6 e whakamahia ana, he puhoi tonu te whakatinanatanga puta noa i te ao. Ko te take nui o tēnei ko te hiahia kia hototahi te IPv6 ki te whatunga IPv4 o nāianei, e hiahiatia ana te whakawhiti me te hekenga. Heoi, i te paunga o ngā wāhitau IPv4 me te pikinga o te hiahia mō te IPv6, he maha ake ngā kaiwhakarato ratonga Ipurangi me ngā whakahaere e tango haere ana i te IPv6, ā, e āta mōhio haere ana ki te mahi takirua o te IPv6 me te IPv4.
Whakarāpopototanga
I roto i tēnei upoko, i tirohia hohonutia e mātou te mahi a te wehewehenga me te whakakotahitanga anō o ngā IP. He rerekē te MTU o ngā hononga raraunga rerekē. Ina nui ake te rahi o te mōkihi i te rohe MTU, ka wehea e te wehewehenga IP te mōkihi kia maha ngā wāhanga iti ake hei tuku, ā, ka huihui anō kia puta he mōkihi katoa mā te tikanga whakakotahitanga IP i muri i te taenga ki te ūnga. Ko te kaupapa o te wehewehenga TCP kia kore ai e pakaru te paparanga IP, ā, ka tukuna anō ngā raraunga iti kua pakaru i te wā e tukuna anōtia ana, kia pai ake ai te pai me te pono o te tuku. Heoi anō, tera pea ētahi atu taputapu paparanga whatunga puta noa i te hononga kawe he iti ake te MTU i tō te kaituku, nō reira ka pakaru tonu te mōkihi i te paparanga IP o ēnei taputapu. Me karo i te wehewehenga i te paparanga IP i ngā wā katoa e taea ana, inā koa i ngā taputapu waenga i roto i te hononga.
Wā tuku: Akuhata-07-2025
