Chapter 7 Connecting to the Internet 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 Practical PC 5th Edition Chapter 7 2 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 Practical PC 5th Edition Chapter 7 3 What is the Internet? Diagram of Internet Connection Practical PC 5th Edition Chapter 7 4 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 Practical PC 5th Edition Chapter 7 5 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 Practical PC 5th Edition Chapter 7 6 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 Practical PC 5th Edition Chapter 7 7 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/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 Practical PC 5th Edition Chapter 7 8 What’s an IP address? You can check your IP address Practical PC 5th Edition Chapter 7 9 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 Practical PC 5th Edition Chapter 7 10 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 Practical PC 5th Edition Chapter 7 11 Hardware: Wired and wireless network devices Ethernet port Practical PC 5th Edition Chapter 7 12 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 Practical PC 5th Edition Chapter 7 13 Hardware: Wired and wireless network devices Diagram of LAN connected to router Practical PC 5th Edition Chapter 7 14 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? Practical PC 5th Edition Chapter 7 15 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 Practical PC 5th Edition Chapter 7 16