Gabatarwa
Duk mun san ƙa'idar rarrabuwa da rashin rarrabawa na IP da aikace-aikacensa a cikin sadarwar hanyar sadarwa. Rarraba IP da sake haɗa IP muhimmin tsari ne a cikin tsarin watsa fakiti. Lokacin da girman fakiti ya wuce iyakar iyakar Raka'a ta watsawa (MTU) na hanyar haɗin hanyar sadarwa, rarraba IP yana raba fakitin zuwa ƙananan gutsuttsura da yawa don watsawa. Ana watsa waɗannan gutsuttsura daban-daban a cikin hanyar sadarwa kuma, da isowa inda za a je, ana sake haɗa su zuwa cikakkun fakiti ta hanyar tsarin sake haɗa IP. Wannan tsari na rarrabawa da sake haɗawa yana tabbatar da cewa ana iya watsa manyan fakiti a cikin hanyar sadarwa yayin da ake tabbatar da sahihanci da amincin bayanan. A cikin wannan sashe, za mu yi nazari sosai kan yadda rarraba IP da sake haɗa suke aiki.
Rarraba IP da Sake Haɗawa
Hanyoyin haɗi daban-daban na bayanai suna da maxsular watsawa daban-daban (MTU); misali, hanyar haɗin bayanai ta FDDI tana da MTU na bytes 4352 da kuma Ethernet MTU na bytes 1500. MTU tana nufin Maxsular watsawa kuma tana nufin maxsular girman fakitin da za a iya watsawa ta hanyar hanyar sadarwa.
FDDI (Fiber Distributed Data Interface) wani ma'auni ne na cibiyar sadarwa ta yankin gida mai sauri (LAN) wanda ke amfani da fiber optic a matsayin hanyar watsawa. Matsakaicin Sakin Watsawa (MTU) shine matsakaicin girman fakitin da za a iya watsawa ta hanyar yarjejeniyar layin haɗin bayanai. A cikin hanyoyin sadarwar FDDI, girman MTU shine bytes 4352. Wannan yana nufin cewa matsakaicin girman fakitin da za a iya watsawa ta hanyar yarjejeniyar layin haɗin bayanai a cikin hanyar sadarwar FDDI shine bytes 4352. Idan fakitin da za a watsa ya wuce wannan girman, yana buƙatar a raba shi don raba fakitin zuwa guntu da yawa waɗanda suka dace da girman MTU don watsawa da sake haɗawa a wurin mai karɓa.
Ga Ethernet, girman MTU yawanci baiti 1500 ne. Wannan yana nufin cewa Ethernet na iya aika fakiti har zuwa baiti 1500. Idan girman fakitin ya wuce iyakar MTU, to fakitin zai raba zuwa ƙananan gutsuttsura don watsawa sannan a sake haɗa shi a inda ake so. Mai masaukin hanyar sadarwa zai iya sake haɗa bayanan IP ɗin da aka raba, kuma na'urar sadarwa ba za ta sake haɗa shi ba.
Mun kuma yi magana game da sassan TCP a baya, amma MSS tana nufin Matsakaicin Girman Kashi, kuma tana taka muhimmiyar rawa a cikin yarjejeniyar TCP. MSS tana nufin girman matsakaicin ɓangaren bayanai da aka yarda a aika a cikin haɗin TCP. Kamar MTU, ana amfani da MSS don iyakance girman fakiti, amma yana yin hakan a matakin sufuri, matakin yarjejeniyar TCP. Yarjejeniyar TCP tana watsa bayanan matakin aikace-aikacen ta hanyar raba bayanan zuwa sassan bayanai da yawa, kuma girman kowane ɓangaren bayanai yana da iyaka ta hanyar MSS.
MTU na kowace hanyar haɗin bayanai ya bambanta domin kowace nau'in hanyar haɗin bayanai daban-daban ana amfani da ita don dalilai daban-daban. Dangane da manufar amfani, ana iya ɗaukar nauyin MTU daban-daban.
A ce mai aikawa yana son aika babban bayanai na byte 4000 don watsawa ta hanyar hanyar haɗin Ethernet, don haka ana buƙatar raba bayanai zuwa ƙananan bayanai guda uku don watsawa. Wannan saboda girman kowace ƙaramin bayanai ba zai iya wuce iyakar MTU ba, wanda shine bytes 1500. Bayan karɓar ƙananan bayanai guda uku, mai karɓa zai sake haɗa su cikin ainihin babban bayanai na byte 4000 bisa ga lambar jerin da kuma daidaitawar kowane bayanai.
A cikin watsawa mai rarrabuwa, asarar wani yanki zai lalata dukkan bayanan IP. Don guje wa wannan, TCP ta gabatar da MSS, inda ake yin rarrabuwa a kan layin TCP maimakon ta hanyar layin IP. Amfanin wannan hanyar ita ce TCP tana da iko mafi daidaito akan girman kowane sashe, wanda ke guje wa matsalolin da ke tattare da rarrabuwa a layin IP.
Ga UDP, muna ƙoƙarin kada mu aika fakitin bayanai mafi girma fiye da MTU. Wannan saboda UDP yarjejeniya ce ta jigilar bayanai mara haɗin kai, wadda ba ta samar da ingantattun hanyoyin aikawa da bayanai kamar TCP ba. Idan muka aika fakitin bayanai na UDP mafi girma fiye da MTU, za a raba shi ta hanyar layin IP don watsawa. Da zarar ɗaya daga cikin gutsuttsuran ya ɓace, yarjejeniyar UDP ba za ta iya sake watsawa ba, wanda ke haifar da asarar bayanai. Saboda haka, domin tabbatar da ingantaccen watsa bayanai, ya kamata mu yi ƙoƙarin sarrafa girman fakitin bayanai na UDP a cikin MTU kuma mu guji watsawa mai rarrabuwa.
Dillalin Fakitin Sadarwa na Mylinking™zai iya gano nau'ikan hanyoyin sadarwa daban-daban ta atomatik VxLAN/NVGRE/IPoverIP/MPLS/GRE, da sauransu, ana iya tantance su bisa ga bayanin martabar mai amfani bisa ga fitowar kwararar ramin halayen ciki ko na waje.
○ Yana iya gane fakitin lakabin VLAN, QinQ, da MPLS
○ Zai iya gano VLAN na ciki da na waje
○ Ana iya gano fakitin IPv4/IPv6
○ Zai iya gano fakitin rami na VxLAN, NVGRE, GRE, IPoverIP, GENEVE, MPLS
○ Ana iya gano fakitin IP da aka raba (Ana tallafawa gano rarrabuwar IP kuma yana goyan bayan sake haɗa rarrabuwar IP don aiwatar da tace fasalin L4 akan duk fakitin rarrabuwar IP. Aiwatar da manufar fitarwa ta zirga-zirga.)
Me yasa aka raba IP da TCP?
Tunda a cikin watsawar hanyar sadarwa, matakin IP zai raba fakitin bayanai ta atomatik, koda kuwa matakin TCP bai raba bayanan ba, fakitin bayanai za a raba shi ta atomatik ta hanyar layin IP kuma a watsa shi yadda ya kamata. To me yasa TCP ke buƙatar rarrabuwa? Shin hakan ba ya wuce gona da iri ba?
A ce akwai babban fakiti wanda ba a raba shi a kan layin TCP ba kuma ya ɓace a lokacin wucewa; TCP zai sake aika shi, amma a cikin babban fakitin gaba ɗaya (kodayake layin IP yana raba bayanan zuwa ƙananan fakiti, kowannensu yana da tsawon MTU). Wannan saboda layin IP bai damu da ingantaccen watsa bayanai ba.
A wata ma'anar, a kan jigilar na'ura zuwa hanyar haɗin yanar gizo, idan matakin jigilar bayanai ya raba bayanai, matakin IP ba zai raba shi ba. Idan ba a yi raba a matakin jigilar bayanai ba, rarrabuwar bayanai na iya yiwuwa a matakin IP.
A taƙaice dai, TCP tana raba bayanai ta yadda ba za a sake raba layin IP ba, kuma idan aka sake watsawa, ƙananan sassan bayanan da aka raba ne kawai ake sake watsawa. Ta wannan hanyar, ana iya inganta ingancin watsawa da amincinsa.
Idan TCP ya rabu, shin matakin IP ɗin ba ya rabu ba?
A cikin tattaunawar da ke sama, mun ambaci cewa bayan rarrabuwar TCP a wurin mai aikawa, babu rarrabuwa a matakin IP. Duk da haka, akwai wasu na'urorin layin hanyar sadarwa a duk faɗin hanyar haɗin sufuri waɗanda ƙila suna da mafi girman na'urar watsawa (MTU) ƙasa da MTU a wurin mai aikawa. Saboda haka, duk da cewa an raba fakitin a wurin mai aikawa, yana sake rarrabuwa yayin da yake wucewa ta layin IP na waɗannan na'urori. Daga ƙarshe, duk tsage-tsage za a haɗa su a wurin mai karɓa.
Idan za mu iya tantance mafi ƙarancin MTU a kan dukkan hanyar haɗin kuma mu aika bayanai a wannan tsayin, babu wani rarrabuwar kawuna da zai faru ko da wane ƙofa aka aika bayanan zuwa gare ta. Wannan mafi ƙarancin MTU a kan dukkan hanyar haɗin ana kiransa hanyar MTU (PMTU). Lokacin da fakitin IP ya isa ga na'urar sadarwa, idan MTU na na'urar sadarwa ta ƙasa da tsawon fakitin kuma an saita tutar DF (Kada Ka Rarraba) zuwa 1, na'urar sadarwa ba za ta iya raba fakitin ba kuma za ta iya sauke shi kawai. A wannan yanayin, na'urar sadarwa ta samar da saƙon kuskure na ICMP (Internet Control Message Protocol) mai suna "Saitawar Rarrabawa Bukatar Amma DF." Za a mayar da wannan saƙon kuskuren ICMP zuwa adireshin tushe tare da ƙimar MTU na na'urar sadarwa. Lokacin da mai aikawa ya karɓi saƙon kuskuren ICMP, zai iya daidaita girman fakitin bisa ga ƙimar MTU don guje wa yanayin rarrabuwa da aka haramta sake.
Rarraba IP abu ne mai mahimmanci kuma ya kamata a guji shi a matakin IP, musamman akan na'urori masu matsakaicin matsayi a cikin hanyar haɗin. Saboda haka, a cikin IPv6, an hana raba fakitin IP ta hanyar na'urori masu matsakaicin matsayi, kuma za a iya aiwatar da rabawa ne kawai a farkon da ƙarshen hanyar haɗin.
Fahimtar Asali game da IPv6
IPv6 sigar 6 ce ta Intanet Protocol, wacce ita ce magajin IPv4. IPv6 tana amfani da tsawon adireshin bit 128, wanda zai iya samar da adiresoshin IP fiye da tsawon adireshin bit 32 na IPv4. Wannan saboda sararin adireshin IPv4 yana ƙarewa a hankali, yayin da sararin adireshin IPv6 yana da girma sosai kuma yana iya biyan buƙatun Intanet na gaba.
Idan ana maganar IPv6, ban da ƙarin sararin adireshi, yana kuma kawo ingantaccen tsaro da iya daidaitawa, wanda ke nufin cewa IPv6 na iya samar da ingantacciyar ƙwarewar hanyar sadarwa idan aka kwatanta da IPv4.
Duk da cewa IPv6 ya daɗe yana wanzuwa, har yanzu ana ci gaba da amfani da shi a duk duniya. Wannan ya faru ne saboda buƙatar IPv6 ta dace da hanyar sadarwar IPv4 da ke akwai, wadda ke buƙatar sauyawa da ƙaura. Duk da haka, tare da gajiyar adiresoshin IPv4 da kuma ƙaruwar buƙatar IPv6, ƙarin masu samar da sabis na Intanet da ƙungiyoyi suna ɗaukar IPv6 a hankali, kuma a hankali suna fahimtar aikin IPv6 da IPv4 a matakai biyu.
Takaitaccen Bayani
A cikin wannan babi, mun yi nazari sosai kan yadda rarrabuwar IP da sake haɗa su ke aiki. Hanyoyin haɗi daban-daban suna da Matsakaici na Watsawa (MTU) daban-daban. Lokacin da girman fakiti ya wuce iyakar MTU, rarrabuwar IP tana raba fakitin zuwa ƙananan gutsuttsura da yawa don watsawa, sannan ta sake haɗa su cikin cikakken fakiti ta hanyar tsarin sake haɗa IP bayan isa inda za a nufa. Manufar rarrabuwar TCP ita ce a sanya layin IP ba ya sake gutsuttsura ba, kuma a sake watsa ƙananan bayanai da aka raba kawai lokacin da aka sake watsawa, don inganta ingancin watsawa da aminci. Duk da haka, akwai wasu na'urorin layin hanyar sadarwa a cikin hanyar haɗin sufuri waɗanda MTU na iya zama ƙarami fiye da na mai aikawa, don haka fakitin zai sake gutsuttsura a layin IP na waɗannan na'urori. Ya kamata a guji rabawa a layin IP gwargwadon iko, musamman akan na'urori masu tsaka-tsaki a cikin hanyar haɗin.
Lokacin Saƙo: Agusta-07-2025
