(DSL), (Asymmetric Digital Subscriber Line, ADSL), (SDSL), (Rate Adaptive DSL, RADSL) (Very high-speed DSL, VDSL).
- 1/1, High-speed DSL (HDSL) 4- 1,544 2,048 /. ISDN 2- 128 /.
Internet ( Internet ) 2- , - . .
, , , . (V.34, V.34+) 3100 , *DSL 1 - . *DSL . 6.38 ADSL-.
. 6.38. ADSL-
ADSL-, , : , , . - 1,5 6 /, - - 16 / 1 /. . , Internet , , . .
ADSL - ADSLAM. 3100 , , ADSLAM.
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ADSL ISDN HDSL - , . , ADSL , . POTS ADSL-. . ISDN HDSL , 64 /.
, , Internet ( ). Internet , , ADSL, , .
*DSL Internet , .
ADSL- . , - DMT, - , , . *DSL , . ADSL , short range short haul . , , , , , 2,048 / (, RAD Data Communications).
Internet . - . 75- 30 /, - 10 /. .
Internet - Internet, 10 8 / 80 /, SONET/SDH . Internet, UUCP, .
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ISDN - .
- (RAS), , .
, , .
dial-in ( ), - dial-out.
, . , - 4800 9600 /.
, , , .
, Internet, Internet - , .
Internet - *DSL, ADSL.
1. DSU/CSU?
2. . , - , ? 500 / 1 /.
3. , 2- , . ?
4. OSI ?
5. , , 1?
6. , , , 100 180 /?
7. 1 STS-1?
8. .25 PAD?
9. , RS-232C, Ethernet, , Ethernet ?
10. PAD , , ?
11. ISDN , 2400 / 9600 /, ?
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12. ISDN , , 100 512 / ?
13. , TCP ( ) , , .25 frame relay?
14. frame relay : CIR, Be CIR (, CIR ). frame relay , - , CIR?
15. , 19,2 /, : .25, frame relay ? , .
16. ? ?
17. , . , VCI , . ?
18. V.90 , V.90. , . ?
19. : ISDN B+D, 64 /, frame relay CIR=64 /?
20. , frame relay. NetBEUI , , , . ?