X.25 e ne e le likhetho tsa mekhoa ea ho etsa marang-rang ka li-1980
X.25 e ne e le seboka se tloaelehileng sa li-protocol tse sebelisetsoang lipuisano tsa packet-switched ka marang-rang a mangata-a WAN . Protocol ke seteisano se lumellanang sa mekhoa le melao. Lisebelisoa tse peli tse latelang li- protocols tse tšoanang li ka utloisisana le ho fapanyetsana lintlha.
Histori ea X.25
X.25 e ile ea ntlafatsoa lilemong tsa bo-1970 ho fetisa lentsoe holim'a melaetsa ea litefouno ea analog- dial-up marang-rang-'me ke e 'ngoe ea lits'ebeletso tsa khale ka ho fetisisa tsa switched. Mekhoa e tloaelehileng ea X.25 e ne e kenyeletsa marang-rang a mochini oa mochini oa mochine o ikemetseng le marang-rang a netefatso ea karete ea mokitlane X.25 e boetse e tšehetsa mefuta e fapa-fapaneng ea terminalframe le li-server. Lilemo tsa bo-1980 e ne e le mekhoa ea theknoloji ea X-25 ha e sebelisoa ke mananeo a sechaba a Compuserve , Tymnet, Telenet le ba bang. Mathoasong a lilemo tsa bo-90, marang-rang a mangata a X.25 a ile a nkeloa sebaka ke Framework Relay United States Mefuta e meng ea batho ba baholo ka ntle ho US e ile ea tsoela pele ho sebelisa X.25 ho fihlela morao tjena. Melao-kholo e mengata e kileng ea hloka X.25 hona joale e sebelisa mokhoa o fokolang oa Internet Protocol. X-25 e ntse e sebelisoa lik'hamera tse ling tsa ATM le marang-rang a netefatso ea karete ea mokitlane.
Sebopeho sa X-25
Karolo e 'ngoe le e' ngoe ea X.25 e na le lintlha tse 128 tsa boitsebiso. Sebopeho sa X.25 se ne se sebetsana le pokello ea liphutheloana mochine oa mohloli, ho tsamaisoa le ho tsosolosa moo ho eang teng. X.25 lisebelisoa tsa thepa ea lipakane ha lia kenyelletsa feela ho fetola le ho thibela mekhoa ea marang-rang empa hape ho hlahloba phoso le ho khutlisetsa mananeo ho hlokahala ha ho hlaheloa. X.25 e tšehetsa meqoqo e mengata ka nako e le 'ngoe ka multiplexing lipakete le ho sebelisa melaetsa e tloaelehileng ea puisano.
X-25 e ile ea fana ka likarolo tse tharo tsa motheo tsa liprotocol:
- Lera la mobu
- Boitsebiso ba lintlha ba lera
- Pakete ea lera
X-25 e etella pele OSI Reference Model , empa lihlahisoa tsa X-25 li tšoana le lerala la motsoako, lesela la li-data le lerarete tsa setšoantšo se tloaelehileng sa OSI .
Ka tumello e amohelehang ea Internet Protocol (IP) e le tekanyetso ea marang-rang a mekhatlo, lik'homphieutha tsa X.25 li fallela lihlahisoa tse theko e tlaase ho sebelisa IP e le marang-rang a tsamaiso ea marang-rang le ho kenya likarolo tse tlase tsa X.25 le Ethernet kapa lihlahisoa tse ncha tsa ATM .