网络工程师教程最新版(第三版)知识要点

112LANMANWAN3OSI/RM12345672123W=f2-f1BB=2W2RR=Blog2N=2Wlog2NWNC=Wlog2(1+S/N)=Wlog2(1+10db/10)S/N4LD1310nm1550nm8.3LED850nm1300nm5062.5510120131040151060171028094B/5BNRZ-I80%6ASKFSKPSK4PSKQPSK7PCM8FDMTDMCDMWDM9101112CRC1mkm+k-12k2CRC1rG(x)2M(x)r03mod2xrM(x)/G(x)Y(x)r4M(x)Y(x)31PSTNX.25ISDNATMxDSLHFCCDMA21ACK2ARQAARQBARQWW2k-1CNARQW2k-13HDLC1234ISU4X.25DTEDCEModemNARQX.25X.21HDLCLAPBX.25PLP5X.25LAPDD6ISDNN-ISDNB-ISDNN-ISDN2B+DB64KbpsD16Kbps30B+DBD64Kbps7ATM53ATMATMAALATM6DDNTESONET80001T124800081T11931.544Mbps87156KbpsT4=6T3T3=7T2T2=4T12E13280008CH0CH16E12.048Mbps64KbpsE5=4E4=16E3=64E2=256E13SONETSDHSONET/SDH4OC-151.84Mbps7xDSLADSLIDSLHDSLSDSLVDSL1xDSLIDSLHDSLSDSLT1/E1xDSLADSLVDSLRADSLInternetVOD2ADSL640Kbps6MbpsIDSLISDN128KbpsHDSL1.5~2MbpsSDSL1.5~2MbpsVDSL1.5~2.3Mbps13~52Mbps8HFC-InternetIPFTTH