, . , 2048 / . . ( 115,2 /). AMI, HDB3, 2B1Q, . RS-232C (V.24 +V.28, X.20bis+X.21bis), RS-423A (V.10, .26), RS-422A (V.11, X.27), RS-449 (V.36), Rs-485, RS-530, V.35 . (2- 4 ), (0,4 /26AWG 0,5 /24AWG) . 4- 0,4-0,5 2 / 2-2,4 , 256 / 9-12 , 32 / 15-20 . 2- 160 / 4,2-5,6 , 144 / 6,5-8,5 . Zelax , . 1500 .
ISDN
ISDN (Integrated Services Digital Network) , . ISDN CCITT 1.120 1984 . Northern Telecom AT&T , . 90- NI-1 (National ISDN 1), . NI-2.
ISDN , . ISDN - (bearer channel , ). , D- (Delta channel). ( ) - , 64 / (64 000 /). - 56 /. (1- 8 ). , 16 64 / . (, ) , ( ). D- , (/). 2-4 . , ISDN , .
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ISDN, , . ISDN , : , , , . , , . , , , . ISDN , , (56 /) . ISDN . : , , . ISDN (.25, Frame Relay) IP IPX. ISDN -, , .
ISDN
ISDN ():
BRI (Basic Rate Interface) , : - 64 / D- 16 / = 144 /.
PRI (Primary Rate Interface) . PRI 23 + D (64 /) = 1536 /. ( ) PRI = 30 + D (64 /) = 1984 /. PRI D- (64 /), NFAS (Non-Facility Associated Signaling).
- -:
0=384 / (6 -);
10=1472 / (23 -);
H11=1536 / (24 -);
12=1920 / (30 -), (1).
BRI , . . ISDN ISDN (ISDN Terminal Adapter). ISDN (ISDN Router).
ISDN . 30. BRI U, S . U- 1 , , . U- , NT-1 (Network Termination ). NT-1 2- U- 4- S/T- . S/T , 7 . U- . U- , U-S/T S/T, ISDN. S/T-, NT-1, , .
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. 30. ISDN
, ISDN, NT-1 -. , , ( -), , () .
NT-2 (Network Termination 2) S-, 8 ISDN. S , S , .
S/T ( S) ISDN- : , , , /, . 1 (Terminal Equipment 1). (POTS, PSTN, R-), ISDN , , 2 (Terminal Equipment 2). S/T (Terminal Adapter) .
ISDN :
U- (Line Termination, LT function), .
V- (Exchange Termination, ET function). ( ) ISDN .
( ) , . 13 U- S-epec .
13