Chapter 7 Connecting to the Internet

2Practical PC 5 th Edition Chapter 7 Getting Started In this Chapter, you will learn: − What is the Internet − Options for Internet service − What is an IP address − How to avoid online intrusions − About Hardware: Wired and wireless network devices

3Practical PC 5 th Edition Chapter 7 What is the Internet? The Internet is the largest computer network – A computer network is a collection of computers and devices 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

4Practical PC 5 th Edition Chapter 7 What is the Internet? Diagram of Internet Connection

5Practical PC 5 th Edition Chapter 7 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 6 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

6Practical PC 5 th Edition Chapter 7 What are the options for Internet service? 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 – Offers one of the fastest connections available to individuals Dial-up Internet service – Uses a voiceband modem and telephone lines – Typically less than $10/month – Access speed is slow

7Practical PC 5 th Edition Chapter 7 What are the options for Internet service? 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 – Can have slower speeds, dropped connections

8Practical PC 5 th Edition Chapter 7 What’s an IP address? Every device has an IP address that identifies it – IP addresses such as 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/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

9Practical PC 5 th Edition Chapter 7 What’s an IP address? You can check your IP address

10Practical PC 5 th Edition Chapter 7 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 9 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

11Practical PC 5 th Edition Chapter 7 Hardware: Wired and wireless network devices The Internet connects many smaller networks sometimes called local area networks (LANs) – Connect computers, printers and 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

12Practical PC 5 th Edition Chapter 7 Hardware: Wired and wireless network devices Ethernet port

13Practical PC 5 th Edition Chapter 7 Hardware: Wired and wireless network devices 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

14Practical PC 5 th Edition Chapter 7 Hardware: Wired and wireless network devices Diagram of LAN connected to router

15Practical PC 5 th Edition Chapter 7 Do we need anonymous digital cash? What do you think? – Have you ever made a purchase from the Internet using a credit card? – 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?

16Practical PC 5 th Edition Chapter 7 Chapter Summary You should now be able to: − Understand what is the Internet − Choose an Internet service option − Understand IP addresses − Avoid online intrusions − Understand wired and wireless network devices