Chitsanzo cha Kulankhulana kwa OSI
Kulankhulana kwa maukonde m'dziko la ukadaulo wazidziwitso kumaphatikizapo magawo ambiri ovuta omwe amagwira ntchito limodzi kuti atsimikizire kuti deta yatumizidwa ndikulandiridwa molondola. Chimodzi mwa zitsanzo zodziwika bwino zomvetsetsa kulumikizana kwa maukonde ndi OSI (Open Systems Interconnection) Model. Yokhazikitsidwa ndi International Organization for Standardization (ISO) mu 1984, OSI Model imapereka dongosolo lamalingaliro lomwe limathandiza kumvetsetsa ndikupanga kulumikizana kwa maukonde. Nkhaniyi ifufuza za OSI Model, magawo ake, ndi kufunika kwake m'miyoyo yathu.
Chiyambi cha Chitsanzo cha OSI
Chitsanzo cha OSI chili ndi zigawo zisanu ndi ziwiri, chilichonse chili ndi ntchito yakeyake komanso chimagwira ntchito motsatira dongosolo. Gawo lililonse limalekanitsa ntchito ndi maudindo kuti lipewe zovuta ndikuthandizira kugwirira ntchito limodzi pakati pa matekinoloje osiyanasiyana a netiweki ndi ma protocol.
1. Gawo Lakuthupi
Gawo loyamba ndi Physical Layer, lomwe limagwira ntchito mwachindunji ndi njira yotumizira deta. Izi zimaphatikizapo zigawo za hardware monga zingwe, ma switch, ndi ma network opanda zingwe. Ntchito yake yayikulu ndikutanthauzira zofunikira zaukadaulo zolumikizira netiweki, kuphatikiza mawonekedwe a chizindikiro, ma voltage, nthawi yotumizira, ndi kuchuluka kwa kusamutsa deta. Popanda gawo lodalirika la physical, kulumikizana ndi deta sikungatheke.
2. Gawo la Ulalo wa Deta (Gawo la Ulalo wa Deta)
Gawo lachiwiri ndi Data Link Layer, lomwe limayang'anira kutumiza kosalakwitsa pakati pa zipangizo zapafupi pa netiweki. Izi zimachitika pogawa deta m'mafelemu (mayunitsi ang'onoang'ono) ndikuyang'anira kuwongolera kayendedwe ka madzi, kuyang'anira zolakwika, ndi kukonza. Ma protocol monga Ethernet ndi Point-to-Point Protocol (PPP) amagwira ntchito pa gawoli.
3. Gulu la Netiweki
Gawo la Network limayang'anira njira zotumizira deta pa netiweki yonse. Mu gawo ili, deta imayikidwa m'magawo otchedwa mapaketi, ndipo ma netiweki ovuta amafunika njira zotumizira deta kuti atsimikizire kuti mapaketi afika komwe akupita kudzera m'njira zosiyanasiyana zomwe zilipo. Njira yodziwika bwino kwambiri mu gawo ili ndi Internet Protocol (IP).
4. Gawo Loyendera
Gawo la Transport limapereka kulumikizana pakati pa zipangizo zolumikizirana. Izi zikuphatikizapo kutumiza deta molongosoka komanso modalirika pogwiritsa ntchito Transmission Control Protocol (TCP) ndi User Datagram Protocol (UDP). TCP imatsimikizira kutumiza deta molongosoka komanso motsatizana, pomwe UDP sipereka kukonza zolakwika koma ndi yachangu.
5. Gawo la Gawo
Gawo lachisanu ndi Gawo la Session, lomwe limayang'anira zokambirana pakati pa mapulogalamu olumikizirana. Izi zimaphatikizapo kukhazikitsa, kusunga, ndi kuthetsa magawo pakati pa zipangizo. Ma protocol monga SQL, NFS, ndi NetBIOS amagwira ntchito pa gawoli, zomwe zimathandiza kuti mapulogalamu azilumikizana bwino.
6. Gawo Lowonetsera
Gawo la Presentation limapereka ntchito zomasulira deta zomwe zimaonetsetsa kuti chidziwitso chotumizidwa kuchokera kwa wotumiza chikhoza kusinthidwa kuti chimveke bwino ndi wolandirayo. Izi zikuphatikizapo kubisa deta ndi kuchotsa deta, kukanikiza deta, komanso kuonetsetsa kuti mitundu ya deta ikugwirizana. Zitsanzo za ma protocol mu gawoli ndi monga ASCII, JPEG, GIF, ndi EBCDIC.
7. Gawo Logwiritsira Ntchito
Gawo lapamwamba la OSI Model ndi Application Layer, lomwe limagwirizana mwachindunji ndi mapulogalamu a pulogalamu omwe amafunikira kulumikizana kwa netiweki. Limagwira ntchito ngati mawonekedwe a ogwiritsa ntchito ndipo limaphatikizapo mautumiki ogwiritsidwa ntchito mwachindunji monga imelo, kusamutsa mafayilo, ndi kusakatula pa intaneti. Ma protocol omwe amagwira ntchito pagawoli ndi monga HTTP, FTP, SMTP, ndi DNS.
Kufunika kwa Chitsanzo cha OSI
Chitsanzo cha OSI chili ndi maudindo angapo ofunikira padziko lonse lapansi la maukonde apakompyuta:
1. Kukhazikitsa miyezo yogwirizana ya kulumikizana ndi maukonde: Mwa kukhazikitsa miyezo yofanana, OSI Model imalola ogulitsa ndi opanga mapulogalamu osiyanasiyana kupanga zida ndi ma protocol omwe amagwirizana.
2. Kumathandiza Kuzindikira ndi Kuthetsa Mavuto: Mwa kugawa mauthenga a pa intaneti m'magawo asanu ndi awiri osiyana, mavuto amatha kuzindikirika mosavuta ndikuthetsedwa pagawo linalake popanda kukhudza dongosolo lonse.
3. Kukula Kozikidwa pa Modular: Chitsanzo cha OSI chimapangitsa kuti pakhale chitukuko cha netiweki yofanana, pomwe zatsopano mu gawo limodzi sizikhudza mwachindunji zigawo zina, zomwe zimapangitsa kuti pakhale chitukuko chosinthasintha.
4. Maphunziro ndi Kafukufuku: Monga chida chofunikira kwambiri chophunzitsira, OSI Model imapereka dongosolo lomveka bwino kwa ophunzira ndi ofufuza kuti amvetsetse ndikuwerenga mozama kulumikizana kwa netiweki.
Kukhazikitsa Kwenikweni mu Network World
Chitsanzo cha OSI chingawoneke ngati chosamveka bwino, koma chimagwira ntchito yofunika kwambiri pa ntchito zenizeni padziko lapansi la maukonde:
– Intaneti: Tikagwiritsa ntchito intaneti, ma protocol osiyanasiyana a OSI amagwira ntchito limodzi kuti tipereke mautumiki omwe timagwiritsa ntchito tsiku lililonse. HTTP (Application Layer) imagwira ntchito pamwamba pa TCP (Transport Layer), yomwe imagwira ntchito pamwamba pa IP (Network Layer).
– Bizinesi: Mu ma network a mabizinesi, monga Ma Local Area Networks (LANs) ndi Ma Wide Area Networks (WANs), mfundo za OSI Model zimagwiritsidwa ntchito popanga zomangamanga zovuta komanso zodalirika.
– Chitetezo cha Network: Chitsanzo cha OSI chimathandiza kusanthula ndi kukhazikitsa mfundo zachitetezo cha network. Gawo lililonse limafuna njira zosiyanasiyana zotetezera deta ku zoopsa zomwe zingachitike.
– Kupanga Mapulogalamu: Opanga mapulogalamu ayenera kumvetsetsa OSI Model kuti apange mapulogalamu omwe angathe kulankhulana pa netiweki. Mwachitsanzo, mapulogalamu a VoIP (Voice over IP) monga Skype amagwiritsa ntchito zigawo zosiyanasiyana za OSI kuti apereke mauthenga a mawu ndi makanema.
Mapeto
Chitsanzo cha OSI ndi chinthu chofunikira kwambiri pa intaneti ya makompyuta, kugawa kulumikizana kwa deta m'magawo asanu ndi awiri osiyana: Thupi, Ulalo wa Deta, Network, Transport, Session, Presentation, ndi Application. Mwa kupereka dongosolo lomveka bwino komanso lofanana, chitsanzochi chimagwira ntchito yofunika kwambiri pakupanga miyezo, kupanga ukadaulo wa netiweki, maphunziro, ndi kuzindikira mavuto a netiweki ndi kuthetsa.
Kumvetsetsa OSI Model ndi gawo loyamba lofunika kwambiri kwa aliyense amene akugwira ntchito muukadaulo wazidziwitso ndi kulumikizana. Limapereka chithunzi chokwanira komanso chokonzedwa bwino cha momwe deta imasunthira kuchokera pamalo ena kupita kwina komanso momwe mitundu yosiyanasiyana ya zida ndi ma protocol amagwirira ntchito limodzi mu dongosolo lovuta la IT.
