TCP Guhuza
Iyo dushakisha urubuga, ohereza imeri, cyangwa ukine umukino kumurongo, akenshi ntabwo dutekereza kumiyoboro igoye inyuma yayo. Ariko, ibyo nintambwe zisa nkiyo neza zemeza ko itumanaho rihamye hagati yacu na seriveri. Imwe mu ntambwe zingenzi ni uburyo bwo guhuza TCP, kandi ishingiro ryibi ni ukuboko kwa gatatu.
Iyi ngingo izaganira ku ihame, inzira n'akamaro k'inzira eshatu ku buryo burambuye. Intambwe ku yindi, tuzasobanura impamvu hakenewe hable handhake eshatu, uburyo byerekana ko habaho umutekano no kwizerwa, kandi bifite akamaro, kandi ni ngombwa guhererekanya amakuru. Hamwe no gusobanukirwa kwimbitse inzira eshatu, tuzumva neza uburyo bubiri bwitumanaho ryurusobe hamwe nukubona neza kwizerwa kwa TCP.
TCP inzira eshatu zamaboko ninzibacyuho za leta
TCP ni protocole ishingiye kuri protocole, isaba gushyiraho umurongo mbere yo kwanduza amakuru. Iyi gahunda yo gushyiraho ishyirwaho ninzira eshatu.
Reka dusuzume neza paki ya TCP yoherejwe muri buri murongo.
Mu ntangiriro, abakiriya na seriveri barafunze. Ubwa mbere, seriveri yumvikanye cyane ku cyambu kandi iri mu bumve, bivuze ko seriveri igomba gutangira. Ibikurikira, umukiriya yiteguye gutangira kugera kurubuga.igikeneye gushiraho ihuriro na seriveri. Imiterere ya paki yambere ihuza niyi ikurikira:
Iyo umukiriya atangije guhuza, itanga numero ya mbere yakurikiranye (umukiriya_isn) hanyuma uyishyire muri "nimero ya" ikurikiranye "yumutwe wa TCP. Mugihe kimwe, umukiriya ashyiraho syn ibendera kuri 1 kugirango yerekane ko paki zisohoka ari paki ya syn. Umukiriya yerekana ko bifuza gushiraho ihuriro na seriveri wohereza paki yambere kuri seriveri. Iyi paki ntabwo ikubiyemo amakuru yimikorere (ni ukuvuga amakuru yoherejwe). Kuri iyi ngingo, imiterere yumukiriya yaranzwe nkuko sy-yoherejwe.
Iyo seriveri yakiriye paki yumukiriya, itangiza umubare wacyo (seriveri_inyuma) hanyuma igashyira uwo mubare muri "Serial nimero" yumutwe wa TCP. Ibikurikira, seriveri yinjiye kubakiriya_Isn + 1 muri "nimero yemerwa" kandi ishyiraho syn hamwe na Ack bits kugeza kuri 1. Muri iki gihe, seriveri iri muri leta ya RCVD.
Umukiriya amaze kwakira paki ya seriveri, ikeneye gukora imyumvire ikurikira kugirango isubize paki ya nyuma: Icyambere, umukiriya ashyiraho ACK biti mumitwe ya TCP ya 1; Icya kabiri, umukiriya yinjiye kuri seriveri ya seriveri_Iyis + 1 muri "kwemeza nimero ya" Hanyuma, umukiriya yohereje paki ya seriveri. Iyi paki irashobora gutwara amakuru kubakiriya kuri seriveri. Iyo bimaze kurangiza, umukiriya azinjira mu bihugu byashyizweho.
Seriveri imaze kwakira igisubizo cyigisubizo kubakiriya, nabwo bihindura igihugu cyashyizweho.
Nkuko mubibona uhereye kumurongo wavuzwe haruguru, mugihe ukora ukuboko kwinziraga eshatu, ukuboko kwa gatatu kwemererwa gutwara amakuru, ariko ukuboko kwambere ntabwo. Iki nikibazo gikunze kubazwa mubiganiro. Iyo habaye ukuboko iminsi itatu yuzuye, impande zombi zinjira mu bihugu byashyizweho, zerekana ko ihuriro ryashyizweho neza, aho umukiriya na seriveri bashobora gutangira kohereza amakuru kuri buri wese.
Kuki handhakes eshatu? Ntabwo kabiri, inshuro enye?
Igisubizo rusange nuko, "Kuberako amaboko atatu yemeza ubushobozi bwo kwakira no kohereza." Iki gisubizo nukuri, ariko nimpamvu yo hejuru gusa, ntabwo itanga impamvu nyamukuru. Muri ibi bikurikira, nzasesengura impamvu zo guhana amanota mabiri kuva mu ngingo eshatu zo kurushaho gukomera kuri iki kibazo.
Ukuboko kw'inzira eshatu zirashobora kwirinda neza kohereza amasaruro inshuro nyinshi (impamvu nyamukuru)
Inzira eshatu zemeza ko impande zombi zabonye nimero yizewe.
Inzitizi eshatu irinda guta umutungo.
Impamvu 1: Irinde kwigana amateka yinjiye
Muri make, impamvu nyamukuru ya hathake yinzira eshatu ni ukwirinda urujijo rwatewe no gutangira ihuza rya kera. Mu rubuga rugoye, kohereza amapaki yamakuru ntabwo buri gihe byoherejwe aho ujya hakurikijwe, kandi udupaki twamakuru ashaje dushobora kugera aho hantu hambere kubera ubwinshi bwimiyoboro nizindi mpamvu. Kugira ngo wirinde ibi, TCP ikoresha uburyo butatu bwo gushyiraho ihuza.
Iyo umukiriya yohereje syces yinshi ihuza amapaki akurikiranwa, mubihe nkibisanzwe byurusobe, ibi bikurikira birashobora kubaho:
1- Ibipaki bishaje byubwoko bigera kuri seriveri mbere yipaki ziheruka.
2- Seriveri izasubiza syspan + ACK paki kumukiriya nyuma yo kwakira paki ya kera.
3- Iyo umukiriya yakiriye Syn + Ack Packet, igena ko guhuza ari amateka yarangiye cyangwa igihe cyashize) ukurikije imiterere yacyo, hanyuma yohereza paki yacyo kuri seriveri yo gukuramo ihuza.
Hamwe nihuza ryamaboko abiri, nta buryo bwo kumenya niba ihuza ryubu ari ihuza ryamateka. Inzitizi eshatu zemerera umukiriya kumenya niba ihuza ryubu ari ihuza ryamateka rishingiye kumiterere iyo yiteguye kohereza paki ya gatatu:
1- Niba ari ihuza ryamateka (nimero ikurikiranye yarangiye cyangwa igihe), paki yoherejwe nuwa gatatu ni paki ya gatatu kugirango ikureho amateka.
2- Niba atari amasezerano yamateka, paki yoherejwe kunshuro ya gatatu ni paki ya ACK, kandi amashami abiri yo gushyikirana agaragaza neza isano.
Kubwibyo, impamvu nyamukuru ko TCP ikoresha uburyo butatu nuko itangiza ihuriro ryo gukumira amateka.
Impamvu 2: Guhuza umubare wambere wimpande zombi
Impande zombi za protocole ya TCP zigomba gukomeza nimero ikurikira, nikintu cyingenzi kugirango hamenyekane neza. Imibare ikurikiranye ifite uruhare runini muri TCP ihuza.Bakora ibi bikurikira:
Uwakiriye arashobora gukuraho amakuru yigana kandi akareba neza amakuru.
Uwakiriye arashobora kwakira paki muburyo bwumubare ukurikirana kugirango umenye ubunyangamugayo bwamakuru.
Inomero ikurikiranye irashobora kumenya paki yamakuru yakiriwe nundi muburanyi, igashyiraho amakuru yizewe.
Kubwibyo, iyo ushizeho umurongo wa TCP, umukiriya yohereje paki yinshi hamwe numubare wambere ukurikirana kandi bisaba seriveri gusubiza hamwe na paki ya ACK yerekana ko yakiriye parike yumukiriya. Noneho, seriveri yohereje sypa paki ifite numero yambere ikurikiranye kubakiriya kandi itegereza ko umukiriya asubiza, rimwe na rimwe, kugirango yemeze ko imibare yambere ikurikiranwa.
Nubwo hashobora no kwerekana urutonde rwibishoboka kandi kugirango yirize imikino ya mbere yimpande zombi, Intambwe ya kabiri n'iya gatatu irashobora guhuzwa nintambwe imwe, bikavamo ibikoresho bitatu. Ariko, amaboko yombi arashobora kwemeza gusa ko umubare wambere wishyaka rimwe wakiriwe neza nundi muburanyi, ariko nta garanti ivuga ko umubare wambere wimpande zombi zishobora kwemezwa. Kubwibyo, hathake eshatu ni amahitamo meza yo gufata kugirango harebwe umutekano no kwizerwa kwa TCP.
Impamvu 3: Irinde guta umutungo
Niba hari "ukuboko kwifashisha" gusa, iyo umukiriya asabwa asabwa murusobe, umukiriya ntashobora kwakira paki ya ACK yoherejwe na seriveri, nuko njye na SYS izaba inzara. Ariko, kubera ko nta munwa wa gatatu uhari, seriveri ntishobora kumenya niba umukiriya yakiriye ACK kwemerwa kugirango ashyireho ihuza. Kubwibyo, seriveri irashobora gusa gushimangira gusa isano nyuma yo kwakira buri kimwe. Ibi biganisha kuri ibi bikurikira:
Guta umutungo: Niba Syn Prin Sand yahagaritswe, bikaviramo kohereza inshuro nyinshi, seriveri izashyiraho byinshi binyuranyije na byinshi nyuma yo kubona icyifuzo. Ibi biganisha kumyanda idakenewe ya seriveri.
Ubutumwa bwogumana: Bitewe no kubura ukuboko kwa gatatu, seriveri nta buryo bwo kumenya niba umukiriya yakiriye neza ACK kwemerwa kugirango ashyireho ihuza. Nkigisubizo, niba ubutumwa bwagumye murusobe, umukiriya azakomeza kohereza 3insaba inshuro nyinshi, bigatuma seriveri yo guhora ashyiraho amasano. Ibi bizongera umuyoboro wiyongera kandi utinda kandi bigira ingaruka mbi kumikorere rusange.
Kubwibyo, kugirango turebe umutekano kandi wizewe kumurongo wumuyoboro, TCP ikoresha uburyo butatu bwo gushiraho ihuriro ryo kwirinda ibi bibazo.
Incamake
TheUmuyoboro wa pakiIkigo gishinzwe guhuza TCP bikorwa hamwe ninzira eshatu. Mugihe cyinzira eshatu, umukiriya yohereza paki hamwe na syn ibendera kuri seriveri, byerekana ko ishaka gushiraho ihuriro. Nyuma yo kwakira icyifuzo cyatanzwe numukiriya, seriveri isubiza paki hamwe na sy flags kumukiriya, byerekana ko icyifuzo cyo guhuza kiremewe, kandi cyohereza nimero yacyo yambere. Hanyuma, umukiriya asubiza hamwe nibendera rya Ack kuri seriveri kugirango yerekane ko ihuriro ryashyizweho neza. Rero, amashyaka yombi muri leta yashizweho kandi arashobora gutangira kohereza amakuru kuri mugenzi wabo.
Muri rusange, inzira yinzira eshatu zo kugenzura TCP igamije guhuza umutekano no kwizerwa, irinde urujijo nimyanda yubushobozi hejuru yamateka, kandi ukemure ko impande zombi zishobora kwakira no kohereza amakuru.
Igihe cyo kohereza: Jan-08-2025
