Kanjani i-Ethernet ubuchwepheshe Fast

Kwaphela isikhathi eside desyatimegabitnaya inethiwekhi yindlela kuphela ukuxhuma amakhompyutha. Nakuba le ndlela kwadingeka inombolo yezici (i-plug-terminators, isiginali ukushayisana, afanayo impedance wave), ke luvame kakhulu. Imishini kwaba ukufakwa akubizi - elula, futhi ijubane 1.25 MB / s suit bonke. Nokho, umthamo kwemininingwane ngocansi kusukela ukuthola ezinkulu njalo ngonyaka, futhi nezidingo inethiwekhi hardware some. Ngakho-ke, kule minyaka 90 ukuze sifake endaweni yesinqumo ephelelwe yisikhathi wafika ubuchwepheshe Fast-Ethernet. bathunjelwa akhawunti, "izifo ebuntwaneni" 10-Mbit amanethiwekhi benqotshwa kakhulu ekuthuthukeni izifiso yokuthi kunezigidi zabasebenzisi kanye abakhiqizi.

I-Ethernet Fast. incazelo

Isikhathi lokuzalwa 1992 angabhekwa ngonyaka ubuchwepheshe. Yingaleso sikhathi lapho iqembu izinkampani wahlanganyela ukudalwa imishini inethiwekhi, kuhlanganise 3Com, SYNOptics nabanye abaningana baye wadala inhlangano ekhethekile ngokuhlanganyela ngokuthi "Fast-Ethernet Alliance". imisebenzi yaso zihlanganisa ukuhlaziya ngentuthuko abakhiqizi ezahlukene, inqubo eyayingase isetshenziswe ukwakha ngesivinini ukuthumela idatha izixazululo. Ngaphezu kwalokho, izimiso kumiswa futhi ukudluliswa kwe-amaphakethe idatha akufanele kube ezahlukene kakhulu amanethiwekhi 10-megabit. Lokhu kwakudingekile ukuze silondoloze kwedivayisi ngokufinyelela CSMA / CD.

Ngawo lowo nyaka e-IEEE Amazinga Association kwamiswa, ogama msebenzi kwakumelwe ukutadisha anikezwa izinkampani 100-megabit ukufinyelela izixazululo. Khona-ke kwaqala izinkampani ngxabano esikhoselweni kanye nentuthuko yabo. Njalo kunjiniyela wafuna ukuqiniseka ukuthi kwaba isinqumo sakhe samukelwa nini njengophawu ejwayelekile.

Ngenxa yalokho, njengoba kuvamisile, abantu abaningi kwadingeka ukuba kwenziwe ngalo umhlatshelo ngu ukusilela. Ngokwesibonelo, ezihlongozwayo 100VG-AnyLAN ubuchwepheshe kusukela HP-AT & T, okuyinto nokobana a isimiso esisha ngokuphelele ukufinyelela Demand Priority, enqatshelwa ngoba kwakungeyona emuva-iyahambisana izixazululo ezikhona 10Base.

Waba yini umphumela wesibindi umsebenzi ukuqashelwa ngo-1995 100-megabit isixazululo Fast-Ethernet standard, 802.3u isiqu.

Izici

Umehluko omkhulu phakathi i-Ethernet Fast kumanduleli wawo - 10 Mbps Base-T - kwaba ushintsho ukuqaliswa ngokomzimba.

Ngaphandle ukuhambisana isixazululo langaphambilini, izinzuzo main lobu buchwepheshe yilezi:

- okwandisa izinga idatha kuze kube 12.5 Mbytes / s (okufanayo 100 Mbps);

- ukusetshenziswa ukufinyelela okungahleliwe;

- kungenzeka ngokusebenzisa izixazululo ezivamile, ngoba umsebenzi walondoloza ukwakha inethiwekhi star emise, futhi ingasetshenziswa umqhubi classical: pair ezisontekile nefayibha.

Njengoba ifomethi Fast-Ethernet amaphakethe idatha abasebenzi isalokhu injalo, kungenzeka ukuba sifinyelele sekuyaphela Uhlelo Oluvumelana Nesixazululi nkinga. Ngakho, ngisho namanje, konke izixazululo kwenethiwekhi ukuze Mbps 100 ngisho 1 Gigabit ahlinzeke 10-Mbps Imodi (kungaba isethwe ukuphoqelela e umshayeli).

Noma kunjalo, kukhona umehluko. Ngokwesibonelo, uzimele ukudluliswa zinkathi liye lehla ngamaphesenti acishe 10 izikhathi (eqinisweni, kungenzeka ukuba sifinyelele ngesivinini enjalo).

Izici izingxenye

Njengoba ukhetho i-Ethernet, ungayisebenzisi ikhebula coaxial, Mbps 100-Ethernet Fast kudinga uxhumano zonke, namajukujuku onke amagatsha abamukelayo. Lokhu kungaba inethiwekhi amakhadi lwamakhompyutha, Izikhumulo futhi Ihabhu (HUB). On line obuphelele komkhawulo ibekwa kuncike hlobo umqhubi. Ngakho, ezisontekile pair yesihlanu isigaba ibanga ovumelekile elingamamitha 100, kodwa ivumela ukusebenza fibre 400 m (Duplex isigamu) 2 km.

Nakuba isibalo sabantwana ukuphinda (repeater) nalo kungagcini, ke akuvimbeli ukudalwa kumanethiwekhi multi-port wesifunda amadivayisi ezinjalo.