Network Communications Chapter 7

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Network CommunicationsChapter 7

• Modems, DSL, Cable Modems and ISDN

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Public Switched Telephone Network (PSTN)
Figure 7.1
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Telephone Carrier Signal(Sine Wave)
Figure 7.2
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Amplitude Shift Keying (ASK)
Figure 7.3
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Frequency Shift Keying (FSK)
Figure 7.4
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90 Degree Phase Shift
Figure 7.5
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Phase Shifting the Carrier
Figure 7.6Note Error in text
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Constellation Diagrams
Figure 7.7QPSK
Figure 7.88-PSK
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8 QAM Modulation

Figure 7.9
Figure 7.10
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56 Kb/sec Modem Connection
Figure 7.11
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ADSL ModemAsymmetric Digital Subscriber Line

Figure 7.12
Figure 7.13
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ADSL Modem Architecture
POTs filters do notoperate on the DSLsignal!
Figure 7.14
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Cable TV Distribution
Figure 7.15
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Hybrid Fiber Coax (HFC)
Figure 7.16
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A Cable Modem Connection
Figure 7.17
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Sharing a Cable/DSL Modem
Should be a Router anda Hub / Switch
Figure 7.18
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ISDN Basic Rate2B D 144 Kb/sec
Figure 7.19
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Using the Basic Rate Interface
2 wires
Figure 7.20
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ISDN Primary Rate23B D (T1)
Figure 7.22
64
Figure 7.21
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ISDN PRI Application
Figure 7.23