, , . , , . - f(t), . , , , , . 19 , . , , . . . , . . = 2*log(V,2) - V - ( 2), H - . . S - , N- , = H*log(1+S/N,2).
:
1. (twisted pair) , , , .
( ) , . ( ) UTP 5 . . , Ethernet, Arcnet Token ring. , , () .
- ( ) - UTP
- ( ) - STP
- ( ) - FTP
- S/FTP
(crossover cable): (, -). .
2. , , , , .
.
3 : , . , . (), () (). - . , . . , . : . , . , , . . .