Cov txheej txheem rau IPv4 tau tsim tawm thaum xyoo 1970s. Thaum ntxov xyoo 1990, daim ntawv thov ntawm WWW tau ua rau muaj kev loj hlob ntawm Is Taws Nem. Nrog rau ntau hom kev thov hauv Is Taws Nem thiab kev sib txawv ntawm lub davhlau ya nyob twg, kev muab IP chaw nyob thoob ntiaj teb tau pib ntsib kev nyuaj siab. Hauv qhov chaw no, xyoo 1999, qhov kev pom zoo IPv6 tau yug los.
IPv6 muaj qhov chaw nyob txog li 128 khoom, uas tuaj yeem daws qhov teeb meem ntawm IPv4 tsis txaus. Txij li qhov chaw nyob IPv4 yog 32-ntsis binary, tus naj npawb ntawm IP chaw nyob uas tuaj yeem sawv cev yog 232 = 42949,9672964 billion, yog li muaj txog 4 billion IP chaw nyob hauv Is Taws Nem. Tom qab kev kho dua tshiab rau 128-ntsis IPv6, IP chaw nyob hauv Is Taws Nem yuav theoretically muaj 2128 = 3.4 * 1038. Yog tias lub ntiaj teb saum npoo av (xws li av thiab dej) npog nrog cov khoos phis tawj, IPv6 tso cai rau 7 * 1023 IP chaw nyob ib square meter; yog tias qhov chaw nyob faib tus nqi yog 1 lab ib microsecond, nws yuav siv sijhawm 1019 xyoo los muab txhua qhov chaw nyob.
Hom ntawv ntawm IPv6 pob ntawv
IP v6 pob ntawv muaj 40-byte hauv paus header (base header), tom qab ntawd nrog 0 lossis ntau dua txuas ntxiv (extension header), thiab tom qab ntawd cov ntaub ntawv. Cov duab hauv qab no qhia txog cov hom ntawv header ntawm IPv6. Txhua pob ntawv IPV 6 pib nrog lub hauv paus header. Ntau qhov chaw hauv lub hauv paus ntsiab lus ntawm IPv6 tuaj yeem cuam tshuam ncaj qha rau cov teb hauv IPv4.
(1) Qhov Version (version) teb yog rau 4 khoom, uas piav qhia txog tus qauv ntawm IP raws tu qauv. Rau IPv6, tus nqi teb yog 0110, uas yog tus lej lej 6.
(2) Kev sib txuas lus hom (chav kawm tsheb), daim teb no occupies 8 khoom, nrog rau qhov tseem ceeb (qhov tseem ceeb) teb muaj 4 ntsis. Ua ntej, IPv6 faib cov kwj mus rau hauv ob pawg, uas tuaj yeem yog kev tswj xyuas congestion thiab tsis tswj congestion. Txhua pawg tau muab faib ua yim yam tseem ceeb. Qhov loj ntawm tus nqi tseem ceeb, cov pab pawg tseem ceeb dua. Rau congestion-tswj, qhov tseem ceeb yog 0 ~ 7, thiab qhov kis tau tus mob ntawm cov pob ntawv no tuaj yeem ua rau qeeb thaum muaj teeb meem tshwm sim. Rau qhov tsis tuaj yeem tswj tau congestion, qhov tseem ceeb yog 8 mus rau 15, uas yog cov kev pabcuam hauv lub sijhawm, xws li kev xa cov kev pabcuam suab lossis video. Cov pob ntawv kis tus nqi rau qhov kev pabcuam no yog qhov tsis tu ncua, txawm tias qee cov pob ntawv poob, nws tsis rov xa rov qab.
(3) Flow mark (Flow lable): Lub teb occupies 20 khoom. Flow yog cov ntaub ntawv ntawm cov pob ntawv hauv Is Taws Nem los ntawm qhov chaw tshwj xeeb mus rau qhov chaw tshwj xeeb (unicast lossis multicast). Tag nrho cov pob khoom uas muaj nyob rau tib lub kwj dej muaj tib lub npe kwj. Lub chaw nres tsheb random xaiv ib daim ntawv qhia ntws ntawm 224-1 cov cim ntws. Flow mark 0 yog tshwj tseg los qhia cov cim tsis siv. Random xaiv ntawm kwj cov ntawv lo los ntawm qhov chaw nres tsheb tsis sib haum xeeb ntawm cov computers. Vim lubroutersiv ib qho kev sib txuas ntawm qhov chaw nyob thiab ntws daim ntawv lo ntawm pob ntawv thaum txuas ib qho kwj nrog ib pob ntawv.
Txhua pob ntawv los ntawm qhov chaw nres tsheb nrog tib daim ntawv lo uas tsis yog xoom kwj yuav tsum muaj tib qhov chaw nyob thiab qhov chaw nyob, tib qhov kev xaiv hop-by-hop header (yog tias qhov header no muaj) thiab tib txoj kev xaiv header (yog tias qhov header no muaj). Qhov zoo ntawm qhov no yog thaum lubroutertxheej txheem ib pob ntawv, tsuas yog xyuas cov ntawv ntws tsis tau kos lwm yam hauv pob ntawv header. Tsis muaj cov ntawv ntws ntws muaj lub ntsiab lus tshwj xeeb, thiab qhov chaw nres tsheb yuav tsum qhia meej txog kev ua haujlwm tshwj xeeb uas nws xav tau txhuarouterua rau nws pob ntawv hauv qhov txuas ntxiv
(4) Net load ntev (Payload Length): Lub teb ntev yog 16 cov khoom, uas qhia txog tus naj npawb ntawm bytes muaj nyob rau hauv IPv6 pob ntawv tshwj tsis yog rau header nws tus kheej. Qhov no qhia tau hais tias ib pob ntawv IPv6 tuaj yeem tuav 64 KB ntawm cov ntaub ntawv. Txij li thaum lub header ntev ntawm IPv6 yog tsau, nws tsis yog yuav tsum tau qhia tag nrho ntev ntawm lub pob ntawv (tus lej ntawm cov header thiab cov ntaub ntawv qhov chaw) raws li nyob rau hauv IPv4.
(5) Tom ntej no header (Next header): 8 ntsis ntev. Qhia txog hom kev nthuav dav header tom qab IPv6 header. Daim teb no qhia txog hom header tam sim ntawd tom qab qhov pib.
(6) Lub hop txwv (Hop txwv): (nyob 8 khoom) txhawm rau tiv thaiv cov pob ntawv kom tsis txhob nyob hauv lub network tsis tas li. Qhov chaw nres tsheb tau teeb tsa ib qho kev txwv hop thaum txhua pob ntawv xa tuaj. Thaum txhua tusrouterxa mus rau lub pob ntawv, tus nqi ntawm daim teb rau hop- limit yuav tsum raug txo los ntawm 1. Thaum tus nqi ntawm hop Limit yog 0, lub pob ntawv yuav tsum muab pov tseg. Qhov no yog sib npaug rau lub neej nyob rau hauv IPv4 header, tab sis nws yog yooj yim dua lub sij hawm xam lub sij hawm nyob rau hauv IPv4.
(7) Qhov chaw IP chaw nyob (Qhov Chaw Nyob): Daim teb no nyob 128 khoom thiab yog tus IP chaw nyob ntawm chaw xa khoom ntawm pob ntawv no.
(8) Qhov chaw IP chaw nyob (Qhov Chaw Nyob): Daim teb no nyob 128 khoom thiab yog tus IP chaw nyob ntawm qhov chaw txais ntawm pob ntawv no.
IPv6 pob ntawv hom yog nyob rau ntawm Shenzhen HDV Photoelectron Technology co., LTD., software kev ua haujlwm, Thiab lub tuam txhab tau coj los ua ke pab pawg software muaj zog rau cov khoom siv sib txuas (xws li: ACONU/ kev sib txuas lusONU/ ntseONU/ fiber ntauONU/XPONONU/GPONONUthiab lwm yam). Rau txhua tus neeg siv khoom kho qhov tshwj xeeb xav tau uas xav tau, kuj cia peb cov khoom ntse dua thiab siab dua.