Nhasi, tichatanga nekutarisa paTCP. Pakutanga kwechitsauko pamusoro pekuisa ma "layering", takataura nezvepfungwa yakakosha. Pa "network layer" uye pazasi, zvinonyanya kutaura nezve "host to host connections", zvinoreva kuti komputa yako inofanira kuziva kuti imwe komputa iri kupi kuti ibatanidzwe nayo. Zvisinei, kutaurirana mu "network" kunowanzo kuve kutaurirana pakati pe "interprocess" kwete kutaurirana pakati pe "intermachine". Saka, TCP protocol inosuma pfungwa ye "port". "Port" inogona kugarwa ne "process" imwe chete, iyo inopa kutaurirana zvakananga pakati pe "application processes" dzinoshanda pane "hosts" dzakasiyana.
Basa re transport layer nderekuti ungapa sei masevhisi ekutaurirana zvakananga pakati pema application processes ari kushanda pama host akasiyana, saka inozivikanwawo se end-to-end protocol. Transport layer inovanza ruzivo rwepakati pe network, zvichiita kuti application process ione sekunge pane logical end-to-end communication channel pakati pe transport layer entities mbiri.
TCP inomirira Transmission Control Protocol uye inozivikanwa se connection-oriented protocol. Izvi zvinoreva kuti application imwe isati yatanga kutumira data kune imwe, maitiro maviri aya anofanira kuita handshake. Handshake inzira yakabatana zvine musoro inoita kuti data riendeswe zvakanaka uye rigamuchirwe zvakanaka. Munguva ye handshake, kubatana kunosimbiswa pakati penzvimbo inobva data nekwairi kuenda nekuchinjana ma control packets akawanda uye kubvumirana pane mamwe ma parameters nemitemo kuti data riendeswe zvakanaka.
Chii chinonzi TCP? (Kubatana kwanguTap yeNetiwekiuyeMutengesi weNetwork Packetinogona kugadzirisa ese TCP kana UDP Packets)
TCP (Transmission Control Protocol) inzira yekutaurirana yekufambisa ine chekuita nekubatana, yakavimbika, uye inotenderera kuburikidza ne byte-stream.
Yakatarisana nekubatana: Kutaurirana kwakanangana nekubatana zvinoreva kuti kutaurirana kweTCP ndekwemunhu mumwe chete, kureva kuti, kutaurirana kwekupedzisira-kusvika-kumagumo, kusiyana neUDP, iyo inogona kutumira mameseji kune mahost akawanda panguva imwe chete, saka kutaurirana kwemunhu mumwe chete-kusvika-kuzhinji hakugone kuwanikwa.
Yakavimbika: Kuvimbika kweTCP kunoita kuti mapaketi aendeswe zvakanaka kune anogamuchira pasinei nekuchinja kwe network link, izvo zvinoita kuti protocol packet format yeTCP ive yakaoma kupfuura yeUDP.
Yakavakirwa paByte-stream: Hunhu hweTCP hunobva pa byte-stream hunobvumira kutumirwa kwemashoko ehukuru hwese uye hunovimbisa kurongeka kwemashoko: kunyangwe meseji yapfuura isati yagamuchirwa zvizere, uye kunyangwe ma byte anotevera agamuchirwa, TCP haizoatumire kune application layer kuti igadziriswe uye ichadonhedza otomatiki mapaketi akafanana.
Kana host A ne host B zvangotanga kubatana, application inongoda kushandisa tambo yekutaurirana yevirtual kutumira nekugamuchira data, nokudaro ichivimbisa kutapurirana kwedata. TCP protocol ine basa rekudzora mabasa akadai sekugadzwa kwekubatana, kudzima, uye kubata. Zvinofanira kucherechedzwa kuti pano tinoti tambo yevirtual inongoreva chete kugadzira kubatana, TCP protocol connection inongoratidza chete kuti mativi maviri anogona kutanga kutapurirana data, uye kuve nechokwadi chekuti data rakavimbika. Ma routing ne transport nodes anobatwa ne network devices; TCP protocol pachayo haina chekuita neruzivo urwu.
Kubatana kweTCP ibasa re full-duplex, zvinoreva kuti host A ne host B zvinogona kutumira data kumativi ese ari maviri mukubatana kweTCP. Kureva kuti, data rinogona kutamiswa pakati pe host A ne host B munzira mbiri.
TCP inochengetedza data kwenguva pfupi mu send buffer yekubatanidza. Iyi send buffer ndeimwe yema cache akaiswa panguva yekukwazisana kwemaoko kwevatatu. Zvadaro, TCP inotumira data riri mu send cache ku receive cache ye destination host panguva yakakodzera. Mukuita, peer yega yega ichave ne send cache uye receive cache, sezvakaratidzwa pano:
Send buffer inzvimbo yekurangarira inochengetwa neTCP inoitwa parutivi rwemutumi iyo inoshandiswa kuchengetedza data rinotumirwa kwenguva pfupi. Kana kubatana kwemaoko kwevatatu kwaitwa kuti pave nekubatana, send cache inogadziriswa uye inoshandiswa kuchengetedza data. Send buffer inogadziriswa zvinoenderana nekuzara kwenetwork uye mhinduro kubva kumugamuchiri.
Receive buffer inzvimbo yekurangarira inochengetwa neTCP inoitwa kudivi rekugamuchira iyo inoshandiswa kuchengetedza data rakagamuchirwa kwenguva pfupi. TCP inochengeta data rakagamuchirwa mu receive cache uye inomirira kuti application yepamusoro iverenge.
Ziva kuti saizi yekutumira cache nekugamuchira cache yakaganhurirwa, kana cache yakazara, TCP inogona kushandisa mamwe maitiro, akadai sekudzora kuzara kwedata, kudzora kuyerera kwedata, nezvimwewo, kuve nechokwadi chekuti data rinotumirwa zvakanaka uye kugadzikana kwenetwork.
Muma network emakombiyuta, kutapurirana kwedata pakati pemahost kunoitwa kuburikidza nezvikamu. Saka chii chinonzi packet segment?
TCP inogadzira chikamu cheTCP, kana chikamu chepaketi, nekukamura rwizi rwunopinda kuita zvidimbu uye kuwedzera misoro yeTCP pachikamu chimwe nechimwe. Chikamu chimwe nechimwe chinogona kutumirwa kwenguva shoma chete uye hachigone kudarika Maximum Segment Size (MSS). Pachinodzika, chikamu chepaketi chinopfuura nepakati pe link layer. Chikamu chepaketi chine Maximum Transmission Unit (MTU), inova ndiyo saizi yepamusoro yepaketi inogona kupfuura nepakati pe data link layer. Chikamu chepaketi chikuru chinowanzo enderana ne communication interface.
Saka musiyano uripi pakati peMSS neMTU?
Muma network emakombiyuta, marongerwo ehurongwa hwepamusoro akakosha zvikuru nekuti anofunga nezvemusiyano uripo pakati pemazinga akasiyana. Layer yega yega ine zita rakasiyana; mu layer yekufambisa, data rinonzi segment, uye mu layer yenetwork, data rinonzi IP packet. Saka, Maximum Transmission Unit (MTU) inogona kufungidzirwa seMaximum IP packet Size inogona kutumirwa ne network layer, nepo Maximum Segment Size (MSS) iri pfungwa ye transport layer inoreva huwandu hwakanyanya hwe data hunogona kutumirwa ne TCP packet panguva imwe chete.
Ziva kuti kana Maximum Segment Size (MSS) yakakura kupfuura Maximum Transmission Unit (MTU), kupatsanurwa kweIP kuchaitwa pa network layer, uye TCP haizopatsanuri data hombe kuita zvikamu zvakakodzera saizi yeMTU. Pachava nechikamu pane network layer chakatsaurirwa kune IP layer.
Chimiro chechikamu chepaketi yeTCP
Ngationgororei mafomati uye zviri mukati meTCP headers.
Nhamba yekutevedzana: Nhamba isina kurongeka inogadzirwa nekombuta kana kubatana kwacho kwasimbiswa semutengo wayo wekutanga kana kubatana kweTCP kwasimbiswa, uye nhamba yekutevera inotumirwa kumugamuchiri kuburikidza neSYN packet. Panguva yekutumira data, mutumi anowedzera nhamba yekutevera zvichienderana nehuwandu hwedata rinotumirwa. Mugamuchiri anotonga kurongeka kwedata zvichienderana nenhamba yekutevera yakagamuchirwa. Kana data rikawanikwa risina kurongeka, mugamuchiri acharongazve data kuti ave nechokwadi chekurongeka kwedata.
Nhamba yekubvuma: Iyi inhamba yekutevera inoshandiswa muTCP kubvuma kugamuchira data. Inoratidza nhamba yekutevera yedata rinotevera iro mutumi anotarisira kugamuchira. Mukubatana kweTCP, mugamuchiri anosarudza kuti ndeapi data agamuchirwa zvinobudirira zvichibva panhamba yekutevera yechikamu chepaketi yedata yakagamuchirwa. Kana mugamuchiri akagamuchira data zvinobudirira, anotumira paketi yeACK kumutumi, ine nhamba yekuzivisa kubvuma. Mushure mekugamuchira paketi yeACK, mutumi anogona kusimbisa kuti data racho risati ragamuchirwa nhamba yemhinduro ragamuchirwa zvinobudirira.
Zvidimbu zvekudzora zvechikamu cheTCP zvinosanganisira zvinotevera:
ACK bit: Kana chidimbu ichi chiri 1, zvinoreva kuti nzvimbo yekupindura yekugamuchira mhinduro inoshanda. TCP inotsanangura kuti chidimbu ichi chinofanira kuiswa pa 1 kunze kwemapaketi eSYN apo kubatana kwacho kwatanga.
RST bit: Kana chidimbu ichi chiri 1, zvinoratidza kuti pane musiyano mukubatana kweTCP uye kubatana kunofanira kumanikidzwa kubviswa.
SYN bit: Kana chidimbu ichi chaiswa pa1, zvinoreva kuti kubatana kwacho kuchasimbiswa uye kukosha kwekutanga kwenhamba yekutevera kwaiswa mumunda wenhamba yekutevera.
Chidimbu chekupedzisira: Kana chikamu ichi chiri 1, zvinoreva kuti hapana imwe data ichatumirwa mune ramangwana uye kubatana kwacho kunodiwa.
Mabasa akasiyana-siyana uye hunhu hweTCP zvinoratidzwa nemaumbirwo ezvikamu zvepaketi zveTCP.
Chii chinonzi UDP? (Mylinking's)Tap yeNetiwekiuyeMutengesi weNetwork Packetinogona kugadzirisa ese TCP kana UDP Packets)
User Datagram Protocol (UDP) inzira yekutaurirana isina kubatana. Kana ichienzaniswa neTCP, UDP haina nzira dzakaoma dzekudzora. Iyo UDP protocol inobvumira maapplication kutumira zvakananga mapaketi eIP akavharirwa pasina kubatana. Kana mugadziri akasarudza kushandisa UDP pachinzvimbo cheTCP, application yacho inotaurirana zvakananga neIP.
Zita rakazara reUDP Protocol ndiUser Datagram Protocol, uye musoro wayo inongova mabyte masere (64 bits), izvo zvinova muchidimbu. Maumbirwo emusoro weUDP ndeekuti:
Nzvimbo dzekuenda uye nzvimbo dzinotangiraChinangwa chavo chikuru ndechekuratidza kuti UDP inofanira kutumira mapaketi kupi.
Saizi yepaketi: Munda wehukuru hwepaketi unobata saizi yemusoro weUDP pamwe nehukuru hwedata
Checksum: Yakagadzirirwa kuve nechokwadi chekuti UDP headers nedata zvinotumirwa zvakavimbika. Basa rechecksum nderekuona kana paine chikanganiso kana kuora kwakaitika panguva yekutumirwa kwepaketi yeUDP kuitira kuve nechokwadi chekuti data racho rakavimbika.
Kusiyana pakati peTCP neUDP muMylinking'sTap yeNetiwekiuyeMutengesi weNetwork Packetinogona kugadzirisa ese TCP kana UDP Packets
TCP neUDP zvakasiyana muzvinhu zvinotevera:
Kubatana: TCP inzira yekufambisa inoenderana nekubatana inoda kuti pave nekubatana kusati kwatanga kutamiswa data. UDP, kune rumwe rutivi, haidi kubatana uye inogona kutamisa data nekukasika.
Chinhu Chebasa: TCP ibasa remapoinzi maviri-kune-one, kureva kuti, kubatana kune mapoinzi maviri chete ekutaurirana. Zvisinei, UDP inotsigira kutaurirana kwe-one-to-one,-to-many, uye many-to-many, izvo zvinogona kutaurirana nemahost akawanda panguva imwe chete.
Kuvimbika: TCP inopa basa rekutumira data nenzira yakavimbika, ichiva nechokwadi chekuti data harina zvikanganiso, harina kurasikirwa, harikoperwe, uye rinosvika kana richidiwa. Kune rumwe rutivi, UDP inoita zvese zvainogona uye haivimbise kuti data rinotumirwa zvakanaka. UDP inogona kurasikirwa nedata uye mamwe mamiriro ezvinhu panguva yekutumira data.
Kudzora kuzara kwemvura, kudzora kuyerera kwemvura: TCP ine nzira dzekudzora kuzara kwedata uye nzira dzekudzora kuyerera kwedata, idzo dzinogona kugadzirisa mwero wekutumirwa kwedata zvichienderana nemamiriro enetwork kuti ive nechokwadi chekuti kutumirwa kwedata kwakachengeteka uye kwakasimba. UDP haina nzira dzekudzora kuzara kwedata uye nzira dzekudzora kuzara kwedata, kunyangwe network yacho yakazara zvakanyanya, haizogadzirise mwero wekutumirwa kwedata neUDP.
Musoro wemusoro: TCP ine musoro murefu, kazhinji mabyte makumi maviri, izvo zvinowedzera kana nzvimbo dzesarudzo dzichishandiswa. UDP, kune rumwe rutivi, ine musoro wakagadzika wemabyte masere chete, saka UDP ine musoro wepasi wemusoro.
Maitiro ekushandisa TCP neUDP:
TCP neUDP maprotocol maviri akasiyana e transport layer, uye ane musiyano mukushandiswa kwemaitiro.
Sezvo TCP iri protocol inotarisa pakubatana, inonyanya kushandiswa mumamiriro ezvinhu apo kutumirwa kwedata kwakavimbika kunodiwa. Mamwe mashandisirwo akajairika anosanganisira:
Kutamisirwa kwefaira reFTP: TCP inogona kuve nechokwadi chekuti mafaira haarasikirwe uye haana kukanganiswa panguva yekutumira.
HTTP/HTTPS: TCP inovimbisa kuvimbika uye kururama kwezviri pawebhu.
Nekuti UDP inzira isina kubatana, haipe vimbiso yekuvimbika, asi ine hunhu hwekushanda zvakanaka uye inoshanda panguva chaiyo. UDP yakakodzera mamiriro anotevera:
Vanhu vakawanda vanosvika panhamba shoma, senge DNS (Domain Name System): Mibvunzo yeDNS inowanzova mapaketi mapfupi, uye UDP inogona kuapedzisa nekukurumidza.
Kutaurirana kwemultimedia kwakadai semavhidhiyo neodhiyo: Kune kutumira multimedia kune zvinodiwa zvakanyanya panguva chaiyo, UDP inogona kupa latency yakaderera kuona kuti data rinogona kutumirwa nenguva.
Kutaurirana kwenhepfenyuro: UDP inotsigira kutaurirana kwemunhu mumwe chete uye kwevakawanda uye inogona kushandiswa pakutumira mameseji ekuparadzira.
Pfupiso
Nhasi tadzidza nezveTCP. TCP inzira yekutaurirana yekubatanidza, yakavimbika, yakavakirwa pa byte-stream. Inovimbisa kutumirwa kwakavimbika uye kugamuchira data zvakarongeka nekugadzira kubatana, kubatana maoko uye kubvuma. Nzira yeTCP inoshandisa maports kuita kuti kutaurirana pakati pemaitiro kuvepo, uye inopa masevhisi ekutaurirana zvakananga kune maitiro ekushandisa ari kushanda pane akasiyana mahost. Kubatana kweTCP kwakazara-duplex, zvichibvumira kutamiswa kwedata panguva imwe chete. Kusiyana neizvi, UDP inzira yekutaurirana isina kubatana, iyo isingape vimbiso yekuvimbika uye yakakodzera kune mamwe mamiriro ane zvinodiwa zvakanyanya panguva chaiyo. TCP neUDP zvakasiyana mumodhi yekubatanidza, chinhu chebasa, kuvimbika, kudzora kuzara, kudzora kuyerera nezvimwe zvinhu, uye mamiriro avo ekushandisa akasiyanawo.
Nguva yekutumira: Zvita-03-2024
