Chapter 7 Connecting to the Internet. Connecting to the Internet FAQs: – What is the Internet? – What are the options for Internet service? – What is

Chapter 7Connecting to the Internet

Connecting to the Internet

• FAQs:– What is the Internet?– What are the options for Internet service?– What is an IP address?– How do I avoid online intrusions?

2Practical PC 6th Edition Chapter 7

What is the Internet?• The Internet is the largest computer network

– A computer network is a collection of computers and related devices that are linked to share data, hardware, and software

– Data is exchanged using TCP/IP, which is a protocol that divides information into packets of data

– The Internet backbone is a network of high-capacity communication links maintained and accessed by:

• Network service providers (NSPs) • Network access points (NAPs)• Internet service providers (ISPs)

– The computer you use to access the Internet is the client computer. Typically you will connect to the Internet using a modem


What is the Internet?


What are the options for Internet service?

• Internet services vary in cost, speed, and reliability– Costs range from U.S. $10 to $100/month– Speeds range from 56 Kbps to 16 Mbps– Connection types

• Symmetrical connections provide the same downstream and upstream data speeds

• Asymmetrical connections are the most popular and have faster downstream data speeds

– Losing your Internet connection is frustrating• Cable connections are very reliable• Wireless connections are not as reliable but are

convenient when you are on the go



• Cable Internet service– Uses same infrastructure as cable television– Offers fastest access speeds– Uses a cable modem

• DSL (digital subscriber line)– Runs over standard phone lines– Can be symmetrical or asymmetrical

• Dial-up Internet service– Uses a voiceband modem and telephone lines– Typically less than $10/month– Access speed is slow



• Satellite Internet service– Distributes access via a personal satellite dish– In rural areas may be only choice other than dial-up– Susceptible to bad weather and slow signal time

• WiMax– Newest technology, limited availability– Transmits data to nearby communication tower

• Mobile broadband– Access to the Internet is through high-speed cellular

technology– Used for PDAs, smartphones, notebooks, tablets, and

netbooks– Can have slower speeds, dropped connections


What’s an IP address?

• Every device has an IP address that identifies it – IP addresses such as 204.127.129.1 are divided by periods into

four segments called octets– Static IP addresses are permanently assigned and are used by

ISPs and Web sites that need to be found at the same address– Dynamic IP address are used by most other users and are

temporarily assigned by your ISP• Dial-up users get a new IP every time• DSL, satellite, and cable users have an always-on connection

with the IP address remaining the same for days, weeks, or months

• Through geolocation, your IP address indicates the general region of the world where your computer resides


What is an IP address?


How do I avoid online intrusions?

• An intrusion is any access to data or programs by hackers, criminals, or other unauthorized persons– Access can be gained through an open port. A port is any

pathway of data in or out of a computer– Port scanning software looks for unprotected computers

and can attack an unprotected computer within 4 minutes– To protect your computer:

• Use online tools to check for open ports• Shut down your computer when not in use• Download operating system security patches• Use personal firewall software


Hardware: Wired and wireless network devices

• The Internet connects many smaller networks sometimes called local area networks (LANs)– Connect computers, printers, and other devices such as

scanners at school, work, and home– Most popular technologies are Ethernet and Wi-Fi

• Ethernet• Wired network technology • Most computers include Ethernet port• Connections are fast, inexpensive, reliable, and fairly

secure





• Wi-Fi– Wireless networking technology uses radio waves– Equipment widely available and fairly affordable– Main advantage is mobility– Security provided by Wireless encryption

• Router is centerpiece of LANs• Support both wired and wireless devices• Controls flow of data• Use as a security device to assign private IP addresses

through network address translation




Do we need anonymous digital cash?

• What do you think?– Have you ever felt uncomfortable providing your credit

card number at an e-commerce site?– Do you think that most people believe that using a credit

card in a restaurant is safer than using a credit card on the Internet?

– Do you think that anonymous digital cash is a good idea?


Documents

Chapter 7 Connecting to the Internet. Connecting to the Internet FAQs: – What is the Internet? – What are the options for Internet service? – What is