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WAN??????

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Title: 4 Last modified by: cwg Created Date: 5/28/1995 4:36:04 PM Document presentation format: Other titles: Times New Roman Arial ... – PowerPoint PPT presentation

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Title: WAN??????


1
?5? ????????
  • ????
  • WAN??????
  • ???WAN??
  • PSTN?xDSL?ISDN?Cable Modem
  • X.25?DDN ?FR ?ATM
  • ?????????????????????????

2
5.1 WAN??
  • WAN???
  • ??????????????
  • ???????????
  • ?????????????????
  • ???????????????????
  • ????????,??????(???)
  • ?????????????,???
  • ????????????????
  • ?????????
  • Pro??????????????
  • Con??????????

3
????????
4
????????
  • X.25???????
  • ??X.25???????????????
  • Frame Relay???
  • ??????????????????
  • ISDN???????
  • ?????????????????????????????
  • DDN?????
  • ???????????????????????
  • xDSL?????
  • ?????????????????????
  • ATM??????
  • ?????????????????????????????

5
????????
  • ???OSI/RM?????
  • ???PSTN?DDN?xDSL?SONET
  • ?????ISDN?FR?ATM
  • ???X.25

6
5.2 ??????
  • ??????????
  • ????????
  • ??????????????(????????)
  • ????(?????)?????

7
1. ????
  • ?????????????????
  • ??????,?????????
  • ????
  • ?????(CO),?????????????
  • ???(?????????)??????
  • ???(??????)?????????

8
  • ?????????
  • PCM??
  • ??????????64kb/s?PCM??????
  • ?????
  • ????????
  • ??PCM????????????
  • E1E5( DS1DS5)
  • ?????????????
  • ?????????????64kb/s?????
  • ???????????,??????56kb/s
  • ??ISDN?xDSL???????????
  • ISDN 128kb/s, xDSL 512kb/s55Mb/s

9
2. SONET?????
  • ?????????WAN????
  • ??????(OC-1)?51.84Mb/s,????OC-192??OC-256(13.271Gb
    /s),?p170?5.3
  • ???ATM(??????)?????
  • ATM?????155.52Mb/s?622.08Mb/s?????OC-3?OC-12
  • ?????????(??)

10
???
???
ATM ???
ATM ???
?? ???
?? ???
SONET???
?? ???
FDDI ???
FDDI
11
  • SONET????
  • ????OSI????
  • ??4???
  • ????????????,????
  • ???????????
  • ?????????,??,????
  • ????????,?????(ATM? FDDI?ISDN?SMDS?)???,?????????
    ?????SONET??
  • ??p171,?5.4

12
  • SONET?????
  • 810??(90?9?),??
  • ????(3?,?27??)
  • ??????3?(9??),????6?(18??)
  • ?????(87?,?783??)
  • ??????1?(9??),???86?(774??)
  • ????????,?125µs????(TDM)

13
  • SONET???
  • ?????,????????????
  • ATM????ISDN???????
  • ?????????
  • SONET????
  • ?????????????????
  • ????
  • ???????????
  • ???????????????
  • ?????????
  • ????????

14
3. xDSL(?????)
  • DSL??????????????????
  • DSL????????????
  • ????
  • ????????????????????????????
  • ???????????????,????????
  • ?????????????!
  • ????4kHz????????????
  • DSL?????
  • ???????????????
  • WWW,??/??/????

15
  • DSL????????
  • ADSL ????????(???????)
  • RADSL ?????????????
  • HDSL ?????????
  • VDSL ??????????
  • SDSL ???HDSL?????(HDSL2)

?? ???? (b/s) ?? ?? ???? POTS??
ADSL/ RADSL ??8M ??768k 3.55.5km ? ??????????? ???? ?
HDSL/ SDSL 1.544M? 2.048M 5km ? T1/E1????????????LAN????????????? ?
VDSL ??52M ??26M 0.31.5km ?? ????????????? ??LAN???????? ?
16
  • DSL?????
  • 2B1Q(??????PAM???)
  • ?4????????2?????
  • ?????,????????????????
  • ???????4kHz??,??????????
  • CAP(?????????)
  • ????????QAM,????????????
  • ?????,?????????29???
  • ??????????
  • DMT(???????)
  • ???????????????????256????4.3125kHz???,???????QAM
    ??
  • ???,DMT???????25632kb/s8192kb/s
  • ????????????,????????
  • ??????????????????????????
  • ??????,?1MHz???????8Mb/s?????
  • ???ADSL???????(ITU-T G.922)?

17
?????????
(S/N)

18
ADSL(????????)
  • ??????,???????
  • ????
  • G.992.1(G.dmt), G.992.2(G.lite)
  • ??????
  • ???CO(??)
  • G.dmt640kb/s, G.lite512kb/s
  • CO???(??)
  • G.dmt6.144Mb/s(??8Mb/s),G.lite1.5Mb/s
  • ?????????????????????????????

19
  • ADSL???
  • ????????????
  • ???????????
  • ?????????????FTP?WWW?????
  • ???????????NEXT??
  • ?????????????????
  • ???????,???????????
  • ?????????,????
  • ????
  • ??04kHz,??30kHz1.1MHz
  • ?????????????/??????
  • ???????,????(???????)?

20
ADSL?????
????????????????,???????????????????????
  • ??????4km????????1.1MHz

21
ADSL????
  • ???????????????
  • ???????
  • ATU-R (ADSL Transmission Unit)
  • ???ADSL Modem?ADSL?????????
  • DMT?????,????,??
  • ???
  • ???????????
  • ??????
  • DSL?????(DSL Access Multiplexer,DSLAM)
  • ADSL?????
  • ???/ATU-C??
  • ??????ADSL Modem????

22
ADSL????
23
ADSL????
  • PPPoE(PPP over Ethernet)
  • ????HUB???????????ATU-R
  • ?????,?????????ATU-R??
  • ??PPPoE???,?PPP?????????
  • ?????????ADSL??

24
4. ????????
  • HFC(????????)
  • ???????CATV????????
  • ??????p181,??????
  • ????
  • ????,??????
  • ????,?????????
  • ????????????(Cable Modem)
  • ????????????,????????(10-30Mb/s)
  • ??
  • ???CATV???????
  • ???????
  • ??????????????,?????
  • ????????,??????,?????????

25
  • ????
  • FTTx
  • xH(ome)?B(uilding)? Z(one)?C(oner)
  • FTTH????,?????,????????
  • ????????FTTB?FTTZ?FTTC?
  • ??????p183????,??????
  • ????????FTTx????????????????
  • FTTxLAN?FTTxxDSL?FTTxWLAN?
  • ???
  • ?????,????155Mb/s,????622Mb/s
  • ?????,????????

26
5.3 ??????????
  • ????
  • PSTN?ISDN??,???144kb/s
  • ???????????/????????LAN?????????
  • ??????
  • ????
  • X.25????????(64kb/s)
  • ??????????
  • ??????(2Mb/s??)
  • ???????,??????????????
  • ??????
  • ????
  • ???????????????
  • ???????????????????,?DDN
  • ??N64kb/s(1N 30),??????E1??
  • ??,????????

27
5.4 ?????????
  • 1. HDLC(??????????)
  • ??
  • SDLC,IBM,SNA????????,1974
  • HDLC,ISO,????????????
  • LAP,CCITT(ITU-T),X.25????????
  • LAPB,ITU-T,?????????
  • ?????????
  • HDLC?????????
  • ??????/??(??????????)
  • ??????(?????)

28
???????????????????????
???????????????????????
  • ?????
  • ????

???????????????,???????,??????????
29
  • ?????????
  • ??????(NRM)
  • ??????,?????????????????
  • ?????????
  • ??????(ARM)
  • ?????????????????,?????????????????????????
  • ?????????
  • ??????(ABM)
  • ??????????????????????????????
  • ????????

30
  • HDLC????

?????????(01111110B,7EH)
????????????????,?????????
???????5???1,??????0?
??????0??(5???1???0???)?
?????????,?????????????????????
???????,????????,?????????????
??????(?????)??????(????)?
??1???????,?0???????,?????254??
?????????,CRC16???????????????
??????????
31
  • HDLC??????
  • ??????1?2????????

N(S)?N(R)??8??,????0-7?8???
N(S)?????? N(R)??????????(????N(R)-1?????????)?
P/F????????????????????,???P/F1??
??????????????????????P/F??1,???
??????
S?2?,???????????
M?5?,??????????
32
  • S?????
  • S00,????(RR?)
  • ??N(R)-1?????,?????N(R)???
  • S01,??(REJ?)
  • ????N(R)??????? (Go_Back_N ARQ) ?
  • S10,?????(RNR?)
  • ??N(R)-1?????,?N(R)?????????????
  • S11,????(SREJ?)
  • ???????N(R)?? (????ARQ)?
  • M?????32???????,??????
  • SNRM/SARM/SABM??????/????/??????
  • DISC????
  • DM???????,????(???????????)
  • UA???????
  • UP?????

33
HDLC??????????
??????????
34
  • 2. PPP(?????)
  • ???????????????????????
  • ??????
  • ???????????????
  • ???????????????????????(LCP)
  • ???????????????????????(NCP)?
  • PPP???
  • ?????????,???????????????
  • ????
  • ?IP?????????
  • ???????????
  • ???????????????????
  • ??????????IP??????????????
  • ??PAP(??????)?CHAP(????????)???
  • ??????????????

35
  • PPP???????(???????)
  • PPP??????????????
  • ????
  • ?????????,????????????????
  • ????
  • ???PPP??????????LCP???????????(??,???????/??LCP?)?
  • ??
  • ??,???????????(LCP???????)?
  • ???????
  • ???????????(IP?IPX?)????,???IP?????????????,PPP???
    ???
  • ?????,??????????,???????
  • ????
  • ???????????????????????????????????????????,PPP???
    ???
  • PPP???????????

36
5.5 ???????(PSTN)
  • ???POTS(????????)
  • ??
  • ????,???????,???????
  • ????????,????????
  • ?????????
  • ?????????MODEM
  • ????????????,???56kb/s
  • ???????

37
  • PSTN?????
  • ???????RS-232(DTE?Modem?????)
  • ??????PPP(?SLIP,??????)
  • ????PPP????????????

???
IP/IPX/
?????
PPP/SLIP
RS-232
???
38
  • ??PSTN?????
  • ??????????,???????IE??
  • ????

39
  • ???????????
  • ??????????
  • ??????????
  • ????(Modem),??????????
  • ???????????????
  • ???
  • ??????????
  • ???,???56kb/s
  • ???????

40
5.6 ???????(ISDN)
  • ??????????????????
  • ??
  • B-ISDN
  • ????,????????(ATM)
  • ?????Up to 622Mb/s or Higher
  • N-ISDN(ISDN, ???)
  • ????,???????????,????????
  • ??????????,????
  • ?????????UNI
  • ????????(????8?,??????3???)
  • ??????,???????

41
  • ISDN?????????
  • D??16kb/s????
  • ??????(????)
  • B??64kb/s????
  • ???????????
  • ?B???????4??????
  • ????,???????????
  • ?????(????),????,????????
  • ????,??ISDN???X.25?????
  • ???,??ISDN????????
  • ???????????????(?????????)???????,????????
  • ??????BRI2BD
  • ?????PRI30BD

42
B?????????,????????,?????????
  • ISDN???????

D
BRI
B1
B2
?????,????????????????,???????
????????,26416144kb/s
43
  • ISDN?????
  • ?????I.430(BRI)?I.431(PRI)
  • ???
  • ??LAPD(I.441/Q.921)
  • ??PPP?FR?LAPB(X.25)?
  • ???
  • ??I.451/Q.931
  • ??IP?X.25

??(D??)
????(B??)
I.451/Q.931
IP/IPX
X.25
???
LAPD
PPP
FR
LAPB
?????
I.430/I.431
???
???? ???? ??? ????
44
  • ISDN??????
  • ?ISDN?,??????????
  • ??????,??NT1
  • ??????????????(?????????????LAN),??NT2
  • ??ISDN?????(?ISDN?????ISDN???),??TE1???
  • ??????(?PC??),??TE2???
  • ISDN?????,???TA,????TE2
  • ????????????
  • ???UNT1?ISDN???????
  • ???T?????NT1(ISDN??)???
  • ???STE1/TA?NT2???
  • ???RTE2?TA???

45
  • ISDN?????????

??????,???????
46
  • ??????ISDN????????

??????????,?????????????
  • ??/????ISDN?????

??????,?????????????????
47
5.7 ?????DDN
  • ?????????????
  • ????????????????
  • ??????????
  • ?????(Permanent Virtual Circuit,PVC)
  • ??????????
  • ??????????
  • DDN?????????????????????????,?????????????????????
    ????????
  • ????????????,???????????,?????????,???????????

48
  • DDN????????2.048Mb/s(E1),??32?64kb/s??(PCM??)
  • ??????lt64kb/s?,???????
  • ????????????PCM???
  • ??????64kb/s?,??????
  • PCM???????????????PCM??,??30?????????(?????/??)?
  • ???????PCM????????????,?????N64kb/s(N131)
  • ???E1???????N????

49
  • DDN?????
  • ?????RS-232?V.35??????
  • ??????ISDN??,?????????
  • PPP?FR?LAPB(X.25)?HDLC?
  • ???IP?X.25?

IP/IPX
X.25
???
PPP
FR
LAPB
HDLC

?????
RS-232 / V.35 /
???
50
  • DDN????
  • ??????????????????????
  • ??????
  • ???????????????(DSU/CSU)?????????/????????
  • DDN?????????????(DCS)
  • NMC????
  • ????????????,???????????,?????????????????????????
    ?????

DSU/CSU???????? 1. ???????????E1????????????? 2.
?E1???????????,???????????????
DDN??
NMC
????
????
DDN??
DDN??
DDN??
51
  • DDN???????
  • ????(??)
  • ??????????????????(????),??????64Kbit/s2.048Mbit/
    s???
  • ???
  • DDN??????(Frame Relay)??,????2.048Mb/s?
  • ????/G3??
  • ????/??????DDN???????(VSM),?VSM????????????????,DD
    N????VSM???????????????
  • ????
  • ????DDN????????????,??????????????????

52
  • DDN???
  • ?????
  • 64kb/s? N64kb/s?2.048Mb/s?
  • ?????
  • ????,?????(?????450µs)?
  • ?????
  • ?????,??????????
  • ????
  • ????????????????
  • ????
  • ???????,???????????????
  • ????,?????
  • ????
  • HOST-HOST?LAN-LAN?LAN-WAN????????????????????????

53
  • ????DDN???????

54
5.8 X.25?????
  • X.25??
  • ?????????????????????DTE?????????DCE??????
  • ???WAN????
  • 1976??CCITT(???ITU-T)??,???????(PDN)
  • 1992???,???64kb/s???2.048Mb/s?
  • X.25???DTE?DCE???,????????????

55
  • X.25??????????
  • ??? OSI????????3?
  • ??????
  • ??????????????
  • ????WAN????????
  • ?????????????????????
  • ????,?????????????
  • ????????
  • ?????PDU???????????X.25???????????
  • ????64kb/s(2.048Mb/s,??)?

56
  • X.25???????
  • ???OSI??????????

?????ITU-T X.21??????,?????15??????(2),
??(2),??(2)?
???????LAPB???????????????????????
?????????(???),?????????,????????
(??,??)???????4095?????
57
  • X.25??????
  • X.25??????????????????
  • ?????????4095?????
  • DTE????????????????????(????16??????)?
  • X.25???????????????PVC??????SVC
  • PVC???????????,????/????
  • ?????????????????????
  • SVC???????????
  • ?????????????????

58
  • X.25????????
  • ????
  • DTE??????,?????????
  • DCE??????,?????
  • ????????Modem
  • ?????????????????????PSE??
  • PAD????/????

PAD??????????X.25????DTE?DCE??,???????????????
?????????,??PSE???????PSE???,????PSE???,??????????
?????
PSE??????????????
59
  • X.25???
  • ????
  • ??????????????????????
  • ????
  • ??????????????????????????????????
  • ?????????????
  • ??????,?????,???????
  • ??????
  • TCP/IP?IPX/SPX?AppleTalk?DECnet?
  • ????????,X.25???????????
  • PDU????X.25????????????????

60
  • X.25????????????
  • ?????????????????
  • ????
  • ????? vs ??
  • ??????
  • ??? vs ???????

X.25 Internet
???? ???
????????????,??????? ????????????,???????
????????????? ???????????????????
61
  • ????X.25????????????

X.25
64kb/s
64kb/s
??Modem
??Modem
???
???
LAN1
LAN2
62
5.9 ???(Frame Relay, FR)
  • 1984??ITU-T??
  • ?ITU-T.451?Q.931?Q.922????
  • ?????1000??????WAN??
  • ???X.25??????????????
  • ????????????????????,?????????????????????????
  • ????????????
  • ???????PC?????????????????

63
  • ????????
  • ???OSI???????????
  • ????????????
  • ???????????????,????X.25????,????????????,????????
    ???????
  • ?????????????????????????????????????????????
  • ?????(PVC/SVC)???????,????????????
  • ??????????????
  • ????????????????????????????
  • IP?IPX?AppleTalk
  • PPP(??TCP/IP?IPX/SPX?NetBEUI)
  • ?????56kb/s?2.048Mb/s?45Mb/s?

64
  • ??????
  • ??????????X.25??????????????????
  • ?????,???????1600?????
  • ???????????????????,???????????,??????????????????
    ????????
  • ??PVC?SVC?????,???????????,????PVC?
  • ???????????,?????,?????????????????
  • ??????????????????(?TCP/IP)???

65
  • ????X.25???

X.25 ???
???? ???????????? ??
????? PVC?SVC,??3??? PVC?SVC,??2???
?/???? PAD FRAD
???? ????? ???,??????????
???? ????? ??????
???? ???????? ??????
?? ????????????? ??
????? ?? ??
FRAD?????/??????????????????????????????,??DTE???
??????LAN???FRAD?????,???????????????????????????
?????,?LAN?????????
66
  • ?????????????X.25???

??
??
??
??
??
??
??
??
??
??
??
???
??
???
????
????
X.25?????????
??????????
??
??
??
??
????
????
???
??
????
????
???
??
X.25?????
????????
67
  • ????????
  • ??????????
  • ??LAN??????
  • ?????
  • ???????????????????,?CAD/CAM??
  • ??????
  • ???????????????????,???????,????????????????
  • ??????
  • ????????????????,?????????????????????????????????
    ??????????????

68
  • ??????????
  • ?????????????
  • ?????????????
  • ??LMI??????
  • ???????????????,?????
  • ??LAPF(Link Access Procedure for Frame-mode
    Bearer Service)????????????

69
  • LAPF??????????
  • ???LAPF???????????
  • ???????
  • ??????????????
  • ????DLCI????????????
  • ??????????
  • ?????
  • ???(??HDLC)

?????????(?????),???????????10??16??23??
????????(Front Explicit Congestion
Notification)???????,?????????????
????????(Back Explicit Congestion
Notification)???????,?????????????
???????????,????????????
??????????????3??4????
70
  • ???WAN???
  • FRS????????
  • FRAD?????/????

??FRAD??????
??FRAD??????
FRS
FRS
FRS
FRS
???WAN
??FRAD??????
??FRAD??????
71
  • ?????????
  • ??DLCI(?????????),DLCI???????(2????????1024?)?
  • DLCI???????,???????????????????DLCI???????
  • FRS??????
  • ????????,FRS???????????
  • FRS????????????????
  • FRS?????DLCI????????????,????????DLCI?????????,???
    ??????????????????,???,??DLCI??????DLCI(????????
    ??DLCI???????)?

72
  • ?NET1??????,?????

Q IP???????DLCI? A ???????????????????
NET1
NET2
R1
102
R2
101
106
100
???A????
IN DLCI OUT DLCI
11 100 12 103
11 101 13 104
11 102 14 105
11
B
22
103
???B????
12
21
IN DLCI OUT DLCI
21 103 22 106
14
104
A
13
105
31
32
C
107
R3
R4
???C????
NET3
NET4
IN DLCI OUT DLCI
31 104 32 107
73
5.10 ??????(ATM)
  • ATM?????????????????????????????????
  • ???????????????????????
  • ??????????????????????
  • ATM????????53??????,????(Cell)
  • ??5??????,48???????
  • ??????????????????
  • ???????10Gb/s,????40Gb/s
  • ?????QoS(????)???
  • ??????????,???????????
  • ATM??????????(B-ISDN)???????
  • ???????,????????
  • ?????????,???FE?GE????

74
  • ATM?????
  • ?????(5?????48??????)
  • ???????
  • ????????????????
  • ????????UTP?STP?MMF?SMF
  • ???1.544Mb/s?10Gb/s
  • ???QoS(??????)??
  • ??4???
  • ?????(CBR)??
  • ?????(VBR)??
  • ?????(ABR)??
  • ?????(UBR)??

CBR?????????,????????????????
VBR?????????,???????,????????
ABR?????????,???????????
UBR??????????,???????????
75
  • ATM??????
  • ????,???OSI??????????
  • ATM??????????????????,????ATM???????????
  • ATM?????,????,??/??????
  • ATM?????????????,???????????????QoS???

OSI
ATM
?????
???
76
  • 1?AAL???( AAL)
  • ??????(????)???,ATM??????
  • ??????????????????
  • ??
  • ??????????48???????,??????????????
  • ?????????????,?????????AAL??????5?AAL
  • AAL1CBR??,?????????
  • AAL2VBR??,????????????
  • AAL3/4VBR??,??LAN??,??????????????
  • AAL5 VBR??,???,????IP?X.25?FR????????????????
  • IP-Over-ATM???????AAL5???TCP/IP??

77
  • AAL???CS???SAR?????

????CS
CS??
CS??

CS-PDU
??????? SAR

SAR-PDU
78
  • 2?ATM?
  • ???ATM????????????
  • ?????SAR-PDU??????
  • ????(????????)
  • ?????????
  • ????????(?????????????)?
  • ATM????

???? (5??)
????(SAR-PDU) (48??)
4 8 16 3 1 8 bits
????????UNI??????????NNI???,???????8???12??VPI?
???????????????????????
?????????????????????????,CLP1??????????
???????????????????????? ????????
???/????????????????????
79
???(VC)????(VP)
  • ????VPI?VCI??????????????
  • VPI?VCI????????(?????????)
  • VC?VP??????????????
  • VC????????ATM????????
  • ????????????????(VC Connection,VCC)
  • VP????????
  • ????????????????(VP Connection,VPC)
  • ????????????????????VP????
  • ??VP????VC
  • ATM???????????????????
  • ???????????,????????????

80
  • ATM?????????
  • VC???
  • ??VC????,???VC???VCI??????VC?????VCI?
  • ?????VP??VC??????VP??VC?
  • ???
  • VP???
  • ??VP????,???VP???VPI??????VP?????VPI?
  • VPI???,?VP????VC????,????
  • VP???
  • ???


81
  • 3?ATM???
  • ?????????????
  • ??25Mb/s10Gb/s
  • ???????????
  • ????
  • ????????PMD
  • ????/?????/???????????????/????????????
  • PMD??
  • ????????SDH/SONET
  • ??????????????E??
  • ????,??????????ATM??
  • ??????TC
  • ?????/??????????????/????????????????????(??????/?
    ?)?HEC??

82
  • ATM?????
  • ????ATM??
  • ??????ATM??

??
83
  • ATM???
  • ??LAN?????
  • ???????
  • ???????????
  • ?????????
  • Windows2000/XP/2003???ATM??
  • ?????
  • ??ATM?LAN-LAN??
  • ??FR?????,????ATM????FR?
  • ?ATM???SMDS(???????)?????DBDQ(IEEE802.6 MAN??)??

84
  • ATM????
  • ???????????????????
  • ATM???????????????
  • ?????????????????????
  • ??????????
  • ????????????????????????
  • ???QoS(??????)??
  • ??????????????????????,???????????????????
  • ???????????????????
  • ????????????????????,????????????
  • ????(????????)????
  • ?????QoS?????????,???????(FE/GE)?ATM????????

85
????
  • WAN??????,??????,???????????????
  • WAN??????????????????
  • WAN???????OSI???3??
  • WAN??????????PPP?HDLC?(??HDLC?LAPB)?
  • ??WAN??
  • PSTN??????,???????
  • ADSL??????,?????????????????
  • ISDN??????,??????????????
  • DDN??????,??????????
  • X.25??????,?????????X.25????????
  • FR???????????,????????
  • ATM???????????????,?B-ISDN???????

86
? ?
  • P220
  • 3?4?7?8?9?14?15
  • ??
  • 1. ?ADSL???????????????,?????????(??????????????)
  • 2. ????????????LAN,?????????????????????????

?????!
87
???? ??(b/s)
??????? 256k
???? 16k-64k
E1??????HiFi 2M
????? 8M-32M
???? 34M
????? 100M
HDTV 140M(???)
?????????? 512M
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