IPv4 ke mofuta oa bone oa Internet Protocol (IP) le protocol ea pele e sebelisoang haholo e thehang motheo oa theknoloji ea kajeno ea inthanete. Sesebelisoa le sebaka se seng le se seng se hokahaneng le Marang-rang se abetsoe nomoro e ikhethileng e bitsoang aterese ea IP. Aterese ea IPv4 ke nomoro ea 32-bit e entsoeng ka li-decimals tse 'nè. Pakeng tsa karohano e 'ngoe le e 'ngoe ea Decimal ke palo pakeng tsa 0 le 255. Mohlala: 192.0.2.235
Matsatsing ana, ka lebaka la mofuta o mocha oa IPv6, IPv4 e ntse e le motheo oa ts'ebetso e mengata ea Marang-rang, 'me lisebelisoa tse ngata li hlophisoa ka IPv4. Boemong bona, lisebelisoa tse ngata ha li khone ho buisana li sebelisa IPv6, e leng se etsang hore batho ba bangata, likhoebo le ba bang ba hloke IPv4. Ka mor'a moo, re tla hlahisa sebopeho sa pakete ea IPv4.
Sebopeho sa pakete ea IPv4
(1)PhetoleloLi-account tsa tšimo bakeng sa li-bits tse 4, tse bonts'ang mofuta oa protocol ea IP.
(2)Bolelele ba Sehlooho sa IP, tšimo ena e sebelisetsoa ho hlalosa bolelele ba sehlooho sa IP, kaha ho na le likarolo tsa boikhethelo ba bolelele bo fapaneng sehloohong sa IP. Karolo ena e na le li-bits tse 4, tse nang le yuniti ea bolelele ba li-byte tse 4, ho bolelang hore boleng sebakeng sena = bolelele ba lihlooho tsa IP (ka li-byte) / bolelele ba yuniti (4 li-byte).
(3)Mofuta oa Tšebeletso: 8 likotoana ka bolelele.
PPP: Linomoro tse tharo tsa pele li hlalosa bohlokoa ba sephutheloana. Ha boleng bo le bohlokoa haholo, data e kholo ke ea bohlokoa haholo
000 (Tsela) Tloaelehileng
001 (Priority) ea bohlokoa, e sebelisetsoang khoebo ea data
010 (Ka potlako) hang-hang, bakeng sa khoebo ea data
011 (Flash) lebelo la khanya bakeng sa phetiso ea lentsoe
100 (Flash Overrides) ka potlako bakeng sa khoebo ea livideo
101 (ea bohlokoa) CRI/TIC/ECP ea bohlokoa bakeng sa ho fetisa lentsoe
110 (Internet Control) Taolo ea marang-rang, e sebelisetsoang taolo ea marang-rang, joalo ka liprothokholo tsa ho tsamaisa
111 (Network Control) taolo ea marang-rang, e sebelisetsoang ho laola marang-rang
DTRCO: Linomoro tse 5 tsa ho qetela
(1000) D tieho: 0: ho lieha ha metsotso, 1: fokotsa tieho ka hohle kamoo ho ka khonehang
(0100) T throughput: 0: max throughput (maximum throughput), 1: Leka ho eketsa sephethephethe ka hohle kamoo u ka khonang
(0010) R ho tšepahala: 0: max throughput, 1: eketsa ho tšepahala
(0001) M litjeho tsa phetisetso: 0: min litšenyehelo tsa Mantaha (bonyane ba tsela e holimo), 1: fokotsa litšenyehelo ka hohle kamoo ho ka khonehang
(0000): e tloaelehileng (tšebeletso e tloaelehileng).
(4)Kakaretso ea bolelele ba pakete ea IP: 16 likotoana ka bolelele. Bolelele ba pakete ea IP e baloang ka li-byte (ho kenyeletsoa hlooho le data), ka hona bolelele bo boholo ba pakete ea IP ke li-byte tse 65 535. Kahoo, boholo ba pakete payload=Bolelele bohle ba pakete ea IP - bolelele ba hlooho ea IP.
(5)Sekhetho: 16 likotoana ka bolelele. Sebaka sena se sebelisoa hammoho le masimo a Lifolakha le Fragment Offer ho arola lipakete tse kholoanyane tsa boemo bo holimo. Ka mor'a mooroutere arola pakete, lipakete tsohle tse nyenyane tse arohaneng li tšoauoa ka boleng bo lekanang, e le hore sesebelisoa sa ho ea se ka khetholla hore na ke pakete efe e leng ea pakete e arohaneng.
(6)Lifolakha: bolelele ba likotoana tse 3.
Nomoro ea pele ea sebaka sena ha e sebelisoe.
Karolo ea bobeli ke karolo ea DF (U se ke Ua Fragment). Ha DF bit e behiloe ho 1, e bontša horerouterha e khone ho arola pakete ea lera e ka holimo. Haeba pakete e ka holimo ea lera e ke ke ea fetisoa ntle le karohano, theroutere tla lahla pakete e ka holimo ebe e khutlisetsa molaetsa oa phoso.
Karolo ea boraro ke karoloana ea MF (More Fragments). Ha theroutere arola pakete e ka holimo, e beha MF bit ho 1 hloohong ea pakete ea IP ntle le karolo ea ho qetela.
(7)Fragment Offset: Bolelele ba li-bits tse 13, tse lekantsoeng ka li-unit tsa 8 octet. E bontša sebaka sa pakete ea IP ka har'a pakete ea motsoako, e sebelisoang ke qetellong ea ho amohela ho bokella le ho tsosolosa IP pakete.
(8)Nako ea ho Phela (TTL): Bolelele ke li-bits tse 8, qalong li entsoe ka metsotsoana (s), empa ha e le hantle li lekantsoe ka hop. Boleng ba kamehla bo khothalletsoang ke 64. Ha lipakete tsa IP li fetisoa, boleng bo itseng bo abeloa tšimo ena pele. Ha pakete ea IP e feta ho e 'ngoe le e' ngoeroutertseleng, e mong le e mongroutertseleng e tla fokotsa boleng ba TTL ba pakete ea IP ka 1. Haeba TTL e fokotsehile ho 0, pakete ea IP e tla lahloa. Tšimo ena e ka thibela lipakete tsa IP ho tsoela pele ho fetisetsoa marang-rang ka lebaka la loops ea ho tsamaisa.
(9)Protocol: 16 likotoana ka bolelele. E sebelisetsoa ho lemoha ho nepahala ha lihlooho tsa IP, empa ha e kenyelle karolo ea data. Hobane e mong le e mongroutere hloka ho fetola boleng ba TTL, theroutere tla boela e bale boleng bona bakeng sa pakete ka 'ngoe e fetang
(10)Hlooho ea Checksum: 16 likotoana ka bolelele. E sebelisetsoa ho lemoha ho nepahala ha lihlooho tsa IP, empa ha e kenyelle karolo ea data. Hobane e mong le e mongroutere hloka ho fetola boleng ba TTL, theroutere tla boela e bale boleng bona bakeng sa pakete ka 'ngoe e fetang
(11)Mohloli le Liaterese tsa Sebaka: Ka bobeli liaterese ke 32 bits. E supa tšimoloho le aterese ea moo e eang teng ea pakete ena ea IP. Ka kopo hlokomela hore ntle le haeba NAT e sebelisoa, liaterese tsena tse peli li ke ke tsa fetoha ts'ebetsong eohle ea phetisetso.
(12)Dikgetho: Ena ke sebaka sa bolelele bo fapaneng. Sebaka sena ke sa boikhethelo 'me se sebelisoa haholo bakeng sa tlhahlobo,' me se ka ngoloa bocha ke sesebelisoa se qalang ha ho hlokahala. Lintlha tsa boikhethelo li kenyelletsa tse latelang:
•Mohloli oa litsela o hlephileng: Fana ka letoto la liaterese tsa IP bakeng sarouterlikhokahano. Lipakete tsa IP li tlameha ho fetisoa hammoho le liaterese tsena tsa IP, empa ho lumelloa ho tlola li-routers tse ngata lipakeng tsa liaterese tse peli tse latellanang tsa IP.
•Tsela e tiileng ea mohloli: Fana ka letoto la liaterese tsa IP bakeng sarouterlikhokahano. Lipakete tsa IP li tlameha ho fetisoa hammoho le liaterese tsena tsa IP, 'me haeba hop e latelang e le sieo tafoleng ea aterese ea IP, e bontša phoso.
•Rekota tsela: Rekota aterese ea IP ea sebopeho se kantle sa router ha pakete ea IP e tloha ho e 'ngoe le e 'ngoerouter.
•Litempe tsa nako: Rekota nako eo pakete ea IP e tlohang ka eonarouter.
•Padding: Hobane yuniti ea bolelele ba hlooho ea IP ke li-bits tse 32, bolelele ba hlooho ea IP e tlameha ho ba palo e felletseng ea li-bits tse 32. Ka hona, kamora khetho ea boikhethelo, protocol ea IP e tla tlatsa li-zero tse 'maloa ho fihlela palo e felletseng ea li-bits tse 32.
Lintlha tsa IPV4 hangata li ka sebelisoa ho tsa khamphani ea ronaONUlisebelisoa tsa marang-rang, le lihlahisoa tsa rona tse amanang le marang-rang tse rekisoang tse chesang li koahela mefuta e sa tšoaneng eaONUlihlahisoa tsa letoto, ho kenyeletsoa ACONU/puisanoONU/bohlaleONU/lebokoseONU, etc. Tse ka holimoONUlihlahisoa tsa letoto li ka sebelisoa bakeng sa litlhoko tsa marang-rang maemong a fapaneng. Amohela bohle ho tla ho ba le kutloisiso e felletseng ea tekheniki ea sehlahisoa.
