1. Introduction to Computers
Lesson 7B
Introduction to Computers

2. Using Plain Old Telephone System (POTS) for Data Communications
A modem translates digital computer signals into analog signals that can travel over standard telephone lines
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3. Using Digital Telephone Lines
Telephone companies are now installing digital telephone lines, which are dedicated to transmitting data in digital format.
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4. Digital Telephone Lines
ISDN T1 T3
DSL

5. Cable Modem Connections
Cable modem technology lets home computer users access the Internet through their cable TV lines
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6. What to Consider When Choosing a Modem
External Modem
Internal Modem
Transmission Speed
Data Compression
Error Correction
Internal vs. External

7. Using Modems for File Transfer
File transfer: the exchange of files between computers
Uploading: sending a file to another computer
Downloading: receiving a file from another computer

8. File Transfer Protocols
Kermit
Xmodem
Ymodem
Zmodem
MNP

9. Networking the Home, the Office, and the Globe
Lesson 7B
Networking the Home, the Office, and the Globe