, AMI, . , ( ), . (Non Return to Zero with ones Inverted, NRZI). , , , - .
, AMI NRZI, . , . , . , , . , . , . , , , (scramble - , ). - , , , , . . , , .
, - . , , - (. 8.9, ). . , , , , . , , . , N , NRZ AMI . - .
(. 8.9, ). Ethernet Token Ring.
, . . , . , - . , . , . , . , ( ) N , ( ) N/2 , AMI NRZ. , , 3N/4. . , - .
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2B1Q
. 8.9, . 2B1Q, - (2) , (1Q), 00 -2,5 , 01 -0,833 , 11 - +0,833 , 10 - +2,5 . , . , NRZ, . , 2B1Q , AMI NRZI. , .
AMI, NRZI 2Q1B. , , . , - .
, . , , . , 4/5, FDDI Fast Ethernet, 4 5 . , , . , 4/5 32 , - 16. 16 , , (code violation). , . , , .
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4/5 .
4/5 , . 4/5 5 , .
, 2 - binary - . , , 8/6 8 6 , . 8/6 , 4/5, 256 36=729 .
, .
, , . , 4/5 100 / 125 . , , . , , .
.
. , :
Bi - , i- , Ai - , i- , Bi- Bi-5 - , , 3 5 , - ( 2). , 110110000001 : B1 = 1 = 1 ( , )
, 110001101111, , .
, :
, , . , ISDN 5 23 , - 18 23 .
, .
Bipolar AMI , .
. 8.10 B8ZS (Bipolar with 8-Zeros Substitution) HDB3 (High-Density Bipolar 3-Zeros) AMI. : - 8, - 5.
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. 8.10 B8ZS HDB3. V - ; 1*- , 0
B8ZS , 8 . : V-1*-0-V-1*. V , , , , 1* - , , , . 8 2 - , - . 8 8 . B8ZS , .
HDB3 . HDB3 , B8ZS. , V. V . , . , 000V, - 1*00V.
, . . 8.11 , , . . , . . 8.11 , NRZ - . , , , , ( 4/5 B8ZS, , 1/4 ). , FDDI, Fast Ethernet, Gigabit Ethernet, ISDN . . .
. 8.11
:
v , .
v (NRZ), .
v , . Ethernet Token Ring.
v NRZ , . :
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i. ( 4/5);
ii. ( 2 1Q).
v , , , FDDI, Fast Ethernet, Gigabit Ethernet.
- , , . , . , , , .
, , . .
EIA/TIA-568A, : ANSI, EIA/TIA Underwriters Labs (UL). EIA/TIA-568 EIA/TIA-568 TSB-36 TSB-40A).
ISO/IEC 11801.
EN50173.
. , , 11801 EN50173 , EIA/TAI-568A.
EIA/TIA Underwriters Labs, Anixter. EIA/TIA-568.
, , - IBM.
- . , , , - , . . , . Ethernet FDDI, , Ethernet FDDI.
, . ( TSB-36 TSB-40A, 568), (), , , , ( 90 ), (, ) , .
, .
, ( ).
(Attenuation). .
(Near End Cross Talk, NEXT). .
( ) - ( ) . (, , Ethernet, 50 ). - 100 120 . (100-200 ) .
- . .
- . , , , . , , ( ). .
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. - . : . -, - . 150 , ; 150 20 - , , ; 20 1 - , . - , . .
. AWG (American Wire Gauge), , 22 AWG, 24 AWG, 26 AWG. , . , . . , , , , . . , , , , , , . , , NEXT .
- .