TCP Ubwishingizi Bwishingizi bwizewe
Twese tumenyereye Porotokole ya TCP nka protocole yizewe, ariko ni gute iremeza ko ubwikorezi bwo gutwara?
Kugirango ugere ku ruhererekane rwizewe, ibintu byinshi bigomba gusuzumwa, nka ruswa ya data, gutakaza, kwigana, hamwe na ret-gahunda. Niba ibyo bibazo bidashobora gukemurwa, kohereza byizewe ntibishobora kugerwaho.
Kubwibyo, uburyo bwo gukoresha TCP nkumubare ukurikirana, kwemeza igisubizo, kohereza, no gucunga ihuza, hamwe no kugenzura idirishya kugirango tugere ku ihererwaho ryizewe.
Muri iyi rupapuro, tuzibanda ku idirishya rinyerera, kugenzura no kugenzura imivukire ya TCP. Uburyo bwo kwisubikwa bukubiye mu gice gikurikira.
Kugenzura imiyoboro
Guhuza urusobe cyangwa kumenya nkumuyoboro wo kugenzura urusobe mubyukuri mubyukuri byerekana isano yoroshye hagati yumushinga nabaguzi. Birashoboka ko waje muriki gihe byinshi kukazi cyangwa mubiganiro. Niba ubushobozi bwumuguzi bwo kubyara burenze urugero ubushobozi bw'umuguzi bwo kurya, bizatuma umurongo ukura ubuziraherezo. Mubibazo bikomeye, urashobora kumenya ko mugihe ubutumwa bwa rabbitq ikirundo cyane, birashobora gutera gutesha agaciro ka seriveri yose ya MQ. Ni nako bimeze kuri TCP; Niba bidasuzumwe, ubutumwa bwinshi buzashyirwa murusobe, kandi abaguzi bazaba barenze ubushobozi bwabo, mugihe ababikora bazakomeza kohereza ubutumwa bwigana, buzagira ingaruka ku mikorere yumurongo.
Kugira ngo ukemure iki kibazo, TCP itanga uburyo bwo kubohereje kugenzura umubare w'amahirwe yoherejwe ku bushobozi nyabwo bwakirwa bw'uwakiriye, buzwi ku bijyanye no kugenzura urujya n'uruza. Uwakiriye akomeza kwakira idirishya, mugihe uwabohereje akomeza kohereza idirishya. Twabibutsa ko aya madirishya ari yo gusa ihuza rimwe gusa kandi ntabwo amasano yose asangira idirishya.
TCP itanga kugenzura ukoresheje impinduka kugirango wakire idirishya. Idirishya ryakira ritanga uwagutumye kwerekana uko cache umwanya ukiboneka. Kohereza kugenzura umubare wamakuru yoherejwe ukurikije ubushobozi nyabwo bwakira.
Uwakiriye yakira amenyesha ko uwagutumye amakuru ashobora kwakira, kandi uwayohereje yohereje kugeza kuri iyi mipaka. Iyi mipaka ni ingano yidirishya, ibuka umutwe wa TCP? Hano hari idirishya ryidirishya, rikoreshwa mu kwerekana umubare wa bytes uwakiriye ashoboye cyangwa afite ubushake bwo kwakira.
Umwanditsi wohereje uzahereza paki yidirishya, ikoreshwa mugutangiza niba uwakiriye abakira abashobora kwakira amakuru. Iyo buffer yakira iri mu kaga ko kuzura, ingano yidirishya yashyizwe ahanini kugirango yitange uwabohereje kugenzura umubare wamakuru yoherejwe.
Dore igishushanyo mbonera cyo kugenzura:
Kugenzura umuyoboro
Mbere yo kumenyekanisha ubushobozi bwimirire, dukeneye kubyumva usibye kwakira idirishya no kohereza idirishya, hakoreshwa no kwiyongera muburyo bwo kohereza ibicuruzwa bitangiye kohereza amakuru kubakira idirishya. Kubwibyo, idirishya ryuzuye kandi ribungabungwa na TCP yohereje. Dukeneye algorithm kugirango duhitemo amakuru akwiye kohereza, kuva kohereza amakuru make cyangwa menshi ntabwo ari byiza, bityo igitekerezo cyidirishya ryinshi.
Mu kugenzura imiyoboro ibanziriza imiyoboro, ibyo twirinze niwe uwehereje wuzuza cache yakiriye hamwe namakuru, ariko ntitwari tuzi ibibera murusobe. Mubisanzwe, imiyoboro ya mudasobwa iri mubidukikije bisangiwe. Nkigisubizo, hashobora kubaho ubwinshi bwurusobe kubera itumanaho hagati yizindi ngabo.
Iyo umuyoboro wuzuye, niba umubare munini wibipaki ukomeje koherezwa, birashobora gutuma ibibazo nko gutinda no gutakaza paki. Kuri iyi ngingo, TCP izasubira inyuma amakuru, ariko gusubiramo bizamura umutwaro kumurongo, bikaviramo gutinda kwinshi no gutakaza paki. Ibi birashobora kwinjira muruziga rukabije kandi ukomeze kwiyongera.
Rero, TCP ntishobora kwirengagiza ibibera kumurongo. Iyo umuyoboro wuzuye, ibitambo bya TCP ubwabyo bigabanya umubare wamakuru yohereza.
Kubwibyo, kugenzura ubwiyongere, bigamije kwirinda kuzuza urusobe rwose hamwe namakuru yatanzwe nuwayohereje. Kugirango ucumure umubare wamakuru uwayohereje agomba kohereza, TCP isobanura igitekerezo cyitwa idirishya ryinshi. Igenzura rya Algorithm rivuga rizerekana ingano yidirishya ryinshi ukurikije urwego rwuzuye urusobe, kugirango tugenzure umubare wamakuru yoherejwe nubwatohereje.
Idirishya ryuzuye? Ibi bihuriye he no kohereza idirishya?
Idirishya ryinshi ni impinduka za leta zibungabungwa nuwatohereje igena umubare wamakuru uwayohereje ashobora kohereza. Idirishya ryinshi rihinduka imbaraga zijyanye nurwego rwumuyoboro.
Idirishya ryohereza ku bunini bw'idirishya hagati y'uwatohereje no kwakira yerekana umubare w'amakuru yakira ashobora kwakira. Idirishya ryinshi no kohereza idirishya rifitanye isano; Idirishya ryo kohereza risanzwe ringana byibuze imvura no kwakira amadirishya, ni ukuvuga, SHND = min (Cwnd, Rwnd).
Idirishya ryinshi CWND zihinduka kuburyo bukurikira:
Niba nta kwiyongera murusobe, ni ukuvuga, nta gihe cyo gusubirwamo bibaho, idirishya ryinshi ryiyongera.
Niba hari ubwinshi murusobe, idirishya ryuzuye riragabanuka.
Uwatohereje agena niba umuyoboro wuzuye witegereza niba paki ya ACK yakiriwe mugihe cyagenwe. Niba uwatohereje atakiriye paki ya ACK mugihe cyagenwe, bifatwa ko umuyoboro wuzuye.
Usibye idirishya ryinshi, igihe kirageze cyo kuganira kuri Algorithm ya TCP. TCP kugenzura algorithm igizwe nibice bitatu byingenzi:
Tangira buhoro:Mu ntangiriro, idirishya ryinshi rya CWND ni nto, kandi uwatohereje yongera idirishya ryimivugo kugirango amenye neza ubushobozi bwurusobe.
Kwirinda kwiyongera:Nyuma yuko idirishya ryinshi rirenze urugero runaka, uwatohereje yiyongera muburyo bwo kugabanya umuvuduko widirishya ryinshi yimodoka kandi wirinde kurenga urusobe.
Kugarura byihuse:Niba ubwiyongere bubaye, uwagutumyeho idirishya ryiyongera kandi yinjira mubyo yakira vuba kugirango amenye aho umuyoboro unyuze muri Acklicate wigana, hanyuma ukomeza kongera idirishya ryinshi.
Gutangira buhoro
Iyo ihuza rya TCP ryashyizweho, idirishya ryinshi CWnd ryashyizwe kumurongo byibuze wa MSS (Ingano ntarengwa) Agaciro. Ubu buryo, ubwitonzi bwambere bujyanye na Mss / RTT bytes / kabiri. Umuyoboro nyawo uboneka mubisanzwe kuruta MSS / RTT, tcp rero irashaka kubona igipimo cyiza cyo kohereza, kirashobora kugerwaho muburyo bwo gutangira.
Muburyo bwo gutangira buhoro, agaciro k'idirishya ryinshi CWnd rizatangizwa kuri Mss 1, kandi igihe cyose igice cya parike cyatanzwe, agaciro ka CWND kiziyongera na MSS imwe, ni ukuvuga agaciro kss 2. Nyuma yibyo, agaciro ka CWND karakubye kabiri kuri buri cyanduzwa neza igice cya paki, nibindi. Inzira yihariye yo gukura irerekanwa muburyo bukurikira.
Ariko, igipimo cyo kohereza ntigishobora gukura; Iterambere rigomba kurangirira igihe kimwe. None, ni ryari kwiyongera kwiyongera kurangira? Kanda buhoro-mubisanzwe birangiza ubwiyongere bwo kohereza muri bumwe muburyo butandukanye:
Inzira ya mbere ni urubanza rwo gutakaza paki mugihe cyo kohereza buhoro. Iyo igihombo cya papa kibaye, TCP ishyiraho idirishya ryayohereje cwnd kugeza 1 kandi ritangira inzira yo gutangira buhoro. Kuri ubu, igitekerezo cyo gutangira buhoro ssthresh yatangijwe, agaciro kayo ka mbere ni kimwe cya kabiri cya CWnd itanga igihome cyipaki. Ni ukuvuga, mugihe ubwiyongere bwagaragaye, agaciro ka SSTHresh ni kimwe cya kabiri cyidirishya agaciro.
Inzira ya kabiri ni uguhuza neza nagaciro k'aka gahoro gahoro ssthure. Kubera ko agaciro ka SSTHresh ari kimwe cya kabiri cyidirishya mugihe ubwinshi bwagaragaye, igihombo cyipaki gishobora kubaho hamwe na buri gushidikanya mugihe Cwnd ari nini kuruta SSTHresh. Kubwibyo, nibyiza gushiraho CWND kuri SSTHresh, bizatera TCP kugirango uhindure uburyo bwo kugenzura amazuke hanyuma urangize buhoro.
Inzira yanyuma itangira irashobora kurangira ariro niba acks eshatu zidasanzwe ziboneka, TCP ikora recrantion yihuta yinjira mukinjira. .
Kwirinda kwiyongera
Iyo TCP yinjiye muri leta igenzura, CWND yashizweho igice cyimibare. Ibi bivuze ko agaciro ka CWND kadashobora gukuba kabiri igihe cyose igice cya papa cyakiriwe. Ahubwo, uburyo bwo kubungabunga abantu bugereranije bwemejwe agaciro ka CWN rwiyongereyeho mss gusa (uburebure bwa packet ntarengwa) nyuma ya buri cyararangiye. Kurugero, nubwo ibinyabuzima 10 byemejwe, agaciro ka CWND kaziyongera na Mss imwe. Nuburyo bwo gukura umurongo kandi bufite kandi imbaraga zo hejuru mugukura. Iyo igihombo cyipaki kibaye, agaciro ka CWND kahinduwe kuri MSS, kandi agaciro ka SSTHresh kashyizwe kuri kimwe cya kabiri cya cwnd. Cyangwa bizahagarika kandi gukura kwa MSS mugihe ibisubizo 3 bya Ack byakiriwe. Niba acks eshatu zidasanzwe ziracyakirwa nyuma yo gukumira agaciro ka CWND, agaciro ka SSTHresh karanditswe mugihe cyanditswe na kimwe cya kabiri cya CWnd na leta yihuta yo gukira.
Gukira vuba
Muri leta yihuta, agaciro k'idirishya ryinshi CWnd ryiyongereyeho mss imwe kuri buriwese akk, ni ukuvuga ACK itagera murukurikirane. Nugukoresha ibice bya paki byatanzwe neza murusobe kugirango utezimbere imikorere yo kohereza bishoboka.
Iyo ack yibice byatakaye ikagera, TCP igabanya agaciro ka CWN hanyuma yinjiza leta yo kwirinda imvururu. Nukugenzura ingano yidirishya ryinshi kandi wirinde gukomeza kwiyongera k'umuyoboro.
Niba hari igihe bibaye nyuma yuburyo bwo kurwanya, imiterere y'urusobe iba ikomeye kandi tcp yimuka kuva mu gihe cyo kwirinda imvura itangira buhoro. Muri iki gihe, agaciro ka Window yidirishya CWND kashyizwe kuri mss 1, uburebure ntarengwa bwa paki, hamwe n'agaciro k'abitangira-gutangira bsthresh yashizweho kimwe cya kabiri cya CWND. Intego yibi ni ukukongeraho buhoro buhoro ingano yidirishya ryimivugo nyuma yumuyoboro ukira kugirango ugabanye igipimo cyacuramurwa hamwe nurwego rwumuyoboro wiyongera.
Incamake
Nka protocole yizewe yizewe, ishyira mu bikorwa tCP yizewe numubare ukurikirana, ushimangira, kugenzura gusubiramo, gucunga ihuza hamwe no kugenzura idirishya. Muri bo, uburyo bwo kugenzura ingendo bugenzura umubare w'amakuru yoherejwe n'uwaguriye ukurikije ubushobozi nyabwo bwakira, yirinda ibibazo by'imivugo no gutesha agaciro. Urwego rwo kugenzura rwiyongera rwiyongera kwimibanire yo mu rubuga ruhindura umubare w'amahirwe yoherejwe n'uwabohereje. Ibitekerezo byidirishya ryinshi hanyuma wohereze idirishya rifitanye isano, kandi umubare wamakuru kuri uwayohereje agenzurwa no guhindura ubunini bwidirishya ryinshi. Gutangira buhoro, kwirinda no gukira byihuse nibice bitatu byingenzi bya TCP kugenzura algorithm, bihindura ubunini bwidirishya ryimivugo binyuze muburyo butandukanye bwo guhuza nubushobozi nubwinshi bwurusobe.
Mu gice gikurikira, tuzasuzuma uburyo bwo gusubiramo TCP burambuye. Uburyo bwo kwisubikwa nigice cyingenzi cya TCP kugirango ugere ku ruhererekane rwizewe. Iremeza amakuru yizewe ya retransmitmitta yazimiye, yangiritse cyangwa yatinze. Ihame n'ingamba zo gushyira mu bikorwa uburyo bwo kwisubikwa bizatangizwa no gusesengurwa birambuye mu gice gikurikira. Komeza ukurikirane!
Igihe cyagenwe: Feb-24-2025
