IIDLC , (superset) HDLC. IIDLC, : LAP, LAPB, LLC (IEEE 802.2), LAPD LAPX. LAPF LAPM. LAP: LAPB (X.25), LAPD (FR, ISDN), LAPF (FR), LAPM () LAPX (Telclex) LAPx.
LAP, LAPB LAPX
LAP HDLC. SARM - - (.. ). .25, 1984 LAPB.
LAPB - . .25 .
, - .
LAPX - HDLC. Teletex.
LAPD LAPF
LAPD - D- ( ISDN) - HDLC. LAPD ISDN, . ( - ) D- 16/64 /.
/ FR. . LAPF.
(modem - modulator-demodulator) - - - , - ( ) .
:
- () ( );
- ;
- , , ;
- : , (: -);
- ;
- (<1200 /), (1200-7200 /) (>9600 /);
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- , ( ) -;
: FSK- (300-1800 /); VSB- (3600, 7200, 19200 / ); QAM- (1200, 9600 /); DPSK- (2400, 4800, 9600 /); - (9600 /) - (48000-64000 /).
.
( - 3,1 ), ( - 56/64 /), ISDN (128 /) (, xDSL).
, .1-11 ( 1). .
: (dial-up) . : -
. . . (.3-10) , (handshaking). , . .
.3-10.
, ARQ, ( ) . ( ), handsliaking'a , . "", " ", .
: (300 /) FSK-, : 1070 ("0") 1270 ("1") : 2025 ("0") 2225 ("1"). : 300-3400 . , (FDX).
FSK 1200 / : 1200 ("0") 2400 ("1"), , "0"-"1" . , (HDX), .
( ) - - , ( ASCII-) .. :
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1-7--1 - - (1)+7- ASCII- (7)+ ()-- (1);
1-7-NP-2 - - (1)+7- ASCII- (7)+ (NP)+2 - (2);
1-7-SP-1 - - (1)+7- ASCII- (7)+"0" "1" (8)+- ( 1);
1-8-NP-1 -- (1)+8- ASCII- (8)+ (NP)+ - (1).
- 10 , , , , , 300 /, 30 / 5 /.
: 110-300 /. , : 1200, 2400 4800 /. .. ( ) . 19,2, 28,8, 33,6
56 /. : , .
.3-8 ITU-T, ISDN- .
Bell, Hayes, MNP ITU-T , .
.3.8 , . ITU-T V.nn. , , .3-8. ( V.38) - , ( handshakinga) - , . V.38, V.36, V.37 - , V.91 ( ) .
3-8. , ITU-T
| ITU-T | / | . 4- . | |||
| V.17 | 14,4 | Async (A) | |||
| V.21 | 0,3 | Async | FDX | FSK | |
| V.22 | 0,6/1,2 | A/Sync | FDX | DPSK | |
| V.22bis | 0,3/1,2/2,4 | A/Sync | FDX | QAM | |
| V.23 | 0,6/1,2 | A/Sync | HDX | FDX | FSK |
| V.26 | 2,4 | Sync | HDX | FDX | DPSK |
| V.26bis | 1,2/2,4 | Sync | HDX | FDX | DPSK |
| V.26ter | 1,2/2,4 | A/Sync | FDX | DPSK | |
| V.27 | 4,8 | Sync | FDX | DPSK | |
| V.27bis | 2,4/4,8 | Sync | HDX | FDX | DPSK |
| V.29 | 9,6/(19,2) | A/Sync | HDX | FDX | QAM |
| V.32 | 4,8/9,6 | A/Sync | FDX | ||
| V.32bis | 14,4 | A/Sync | FDX | QAM/TCM | |
| V.32ter | 19,2 | A/Sync | FDX | ||
| V.33 | 14,4 | Sync | FDX | QAM/TCM | |
| V.34 | 28,8 | Sync | FDX | TCM | |
| V.34bis | 28,8/33,6 | Sync | FDX | TCM | |
| V.36 | 48/58/64/72 | Sync | PCM | ||
| V.37 | 96/112/144/168 | Sync | FDX | PCM | |
| V.38 | 48/56/64 | Sync | PCM | ||
| V.61 | 4,8/9,6/12/14,4 | Sync | FDX | QAM | |
| V.90 | 33,6/56 | Sync | FDX | PCM | |
| V.91 | Sync | PCM |
.. , V.32, .. , 9600 /.
- - . , .. . V.42 V.42bis V.44.
