I- alleith algorithm , ebizwa nge-engineer uJohn Nagle, yenzelwe ukunciphisa ukuhlanganiswa kwenethiwekhi okubangelwa "izinkinga zamaphakethe amancane" nezicelo ze-TCP . Ukuqaliswa kwe- UNIX kwaqala ukusebenzisa i-algorithm ka-Nagle ngawo-1980, futhi ihlala isici esijwayelekile se-TCP namuhla.
Indlela i-Algorithm ye-Nagle esebenza ngayo
I-algorithm ka-Nagle ihlela imininingwane ekuhambeni kokuthumela kwezicelo ze-TCP ngendlela ebizwa ngokuthi i- nagling . Ithola imiyalezo encane futhi iqoqe ibe ngamaphakethe we-TCP amakhulu ngaphambi kokuthumela idatha yonkana yocingo, ngaleyo ndlela igweme ukukhiqizwa kwezinombolo ezinkulu ezingadingekile zamaphakethe amancane. Ukucaciswa kobuchwepheshe be-Nagle's algorithm kwanyatheliswa ngo-1984 njengoRFC 896. Izinqumo zemininingwane eminingi ukuqoqa futhi ukuthi ukulinda isikhathi eside phakathi kokuthunyelwa kubalulekile ekusebenzeni kwayo yonke.
I-Nagling ingasebenzisa ngokuphumelelayo ukusetshenziswa komkhawulokudonsa woxhumano lwenethiwekhi ngezindleko zokwengeza ukulibaziseka ( latency ). Isibonelo esichazwe ku-RFC 896 sibonisa izinzuzo ezingaphumelela kwe-bandwidth kanye nesizathu sokudalwa kwayo:
- Isicelo se-TCP esithinta izinkinobho zekhibhodi futhi sifuna ukuxhumana nomlingisi ngamunye othayishiwe kumamukeli, angenza uchungechunge lwemiyalezo ngayinye equkethe i- byte yedatha.
- Ngaphambi kokuba le milayezo ingathunyelwa kunethiwekhi, ngamunye kumele ahlanganiswe nolwazi lwe- TCP njengenhloko edingekayo yi-TCP / IP. Inhloko ngayinye isayizi ngobukhulu phakathi kwama-byte angu-20 no-60.
- Ngaphandle kokuphazamiseka, lolu hlelo lokusebenza lwesibonelo luzokhiqiza imilayezo yenethiwekhi equkethe ukwaziswa okungu-95% noma ngaphezulu kwekhanda (okungenani ama-bytes angu-20 kwangu-21) no-5% noma ngaphansi kwedatha yangempela kusuka kwikhibhodi yomthumeli. Ukusebenzisa i-algorithm ye-Nagle, idatha efanayo ingathunyelwa ngokusebenzisa imilayezo eminingi embalwa futhi ingu-95% wezinto eziqukethwe ulwazi lwekhibhodi - imali enkulu kakhulu yokulondolozwa kwe-bandwidth.
Izicelo zilawula ukusetshenziswa kwazo kwe-algorithm ye-Nagle ne-TCP_NODELAY yokwenza uhlelo lokusekela. Ama-Windows, i-Linux, ne-Java konke kuvame ukunika amandla i-Nagle ngokuzenzakalelayo, ngakho-ke izinhlelo zokusebenza ezibhaliwe kulezo zindawo zidinga ukucacisa i-TCP_NODELAY uma ifuna ukushintsha i-algorithm.
Ukulinganiselwa
I-algorithm ka-Nagle isetshenziswa kuphela nge-TCP. Amanye ama-protocol ahlanganisa iDP awasekeli.
Izinhlelo ze-TCP ezidinga impendulo yenethiwekhi ngokushesha, njengokubiza kwefoni ye-intanethi noma imidlalo yokudubula yomuntu wokuqala, kungenzeka ukuthi ingasebenzi kahle uma i-Nagle inikwe amandla. Ukulibaziseka okwenziwe ngenkathi i-algorithm ithatha isikhathi esengeziwe ukuqoqa izingxenye ezincane zedatha ndawonye kungabangela ilagi ebonakalayo ebonakalayo esikrinini noma ekusakazweni kwomsindo wedijithali. Lezi zicelo ngokuvamile zikhubaza i-Nagle.
Le algorithm yenziwa ekuqaleni ngenkathi amanethiwekhi wekhompuyutha asekelwa umkhawulokudonsa kakhulu kunanamuhla. Isibonelo esichazwe ngenhla sisekelwe ekuhlangenwe nakho kukaJohn Nagle ku-Ford Aerospace ekuqaleni kwawo-1980, lapho ukuhweba ukuhweba okuhamba kancane, inethiwekhi enokude ebhekene nensimbi yayenza ingqondo. Kukhona izimo ezincipha kakhulu lapho izinhlelo zokusebenza zenethiwekhi zingazuza ku-algorithm yakhe namuhla.