" " , . , . 25 . .
. 13. : (UTP) (); ();
(STP) ()
(UTP - Unshielded Twisted Pair) (. 13, ), (. 13, ). (STP - Shielded Twisted Pair) (. 13, ). , , , . , , , . UTP 100 , STP 100, 120 150 . RJ-45. RJ-45 . , 8-, () , , . .
() MDI (Media Dependent Interface), . () MDIX (Media Dependent Interface Xover).
. 14. "" (crossover) Ethernet ();
()
MDI MDIX (.. MDI) "" (. 14, ). MDI (, - . 14, ) MDIX ( - . 14, ) "" (crossover) ( - RS-232C). RJ-45 "MDI-MDIX" MDI, "" .
( , , , ) (). (HUB) . , , , , ( 72 ), . 2,5 . . . 15 Ethernet. 16 RJ-45 AUI . , . , .
|
|
. 15. Ethernet 10Base-T
(4-16) , . , . , (Ethernet 10, 100, 1000 /, Token Ring, FDDI, ATM) ( , , ) [3] , .
, .
-. , , ( ) . . , -, , - . ( 1 ). - - . . , .
2-3 , . -. , . () , . 60% . . , .
, . (Patch panel), .
[3]. 1 2 , . . . ( - ).
|
|
, 4-12 , .
(Patch cord) 1-2 . Patch cord (crossover) . , . 16.