Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Computer security wikipedia , lookup
Policies promoting wireless broadband in the United States wikipedia , lookup
Distributed firewall wikipedia , lookup
Wireless security wikipedia , lookup
Computer network wikipedia , lookup
Network tap wikipedia , lookup
Zero-configuration networking wikipedia , lookup
Wake-on-LAN wikipedia , lookup
Airborne Networking wikipedia , lookup
Piggybacking (Internet access) wikipedia , lookup
Technology In Action Chapter 7 Chapter 6 Summary Questions • How can I determine whether I should upgrade my existing computer or buy a new one? • What does the CPU do and how can I evaluate its performance? • How does memory work and how can I evaluate how much memory I need? • What are the computer’s main storage devices and how can I evaluate whether they match my needs? © 2006 Prentice-Hall, Inc. NEXT SLIDE 1 Technology In Action Chapter 7 Chapter 6 Summary Questions • What components affect the output of video and how can I evaluate whether they are meeting my needs? • What components affect the quality of sound and how can I evaluate whether they are meeting my needs? © 2006 Prentice-Hall, Inc. NEXT SLIDE 2 Technology In Action Chapter 7 Technology In Action Chapter 7 Networking and Security: Connecting Computers and Keeping Them Safe from Hackers and Viruses © 2006 Prentice-Hall, Inc. NEXT SLIDE 3 Technology In Action Chapter 7 Topics • • • • • • • Networking fundamentals Network architecture Network components Peer-to-peer networks Computer threats Computer safeguards Computer viruses © 2006 Prentice-Hall, Inc. NEXT SLIDE 4 Technology In Action Chapter 7 Networking Fundamentals • Computer network: – Two or more computers connected together – Nodes • Benefits of a network: – Sharing resources – Transferring files – Sharing internet © 2006 Prentice-Hall, Inc. NEXT SLIDE 5 Technology In Action Chapter 7 Network Architecture • Network designs: – Locally controlled: Peer-to-peer (P2P) – Centrally controlled: Client/server Peer-to-peer Client/ server © 2006 Prentice-Hall, Inc. NEXT SLIDE 6 Technology In Action Chapter 7 Peer-to-Peer Networks • Nodes communicate with each other: – Peers • Share peripheral devices: – Printers – Scanners • Home and small office networks © 2006 Prentice-Hall, Inc. NEXT SLIDE 7 Technology In Action Chapter 7 Client/Server Networks • Client computers: – Users • Server computers: – Provide resources to clients – Central control unit • Internet © 2006 Prentice-Hall, Inc. NEXT SLIDE 8 Technology In Action Chapter 7 LANs and WANs • Local area network (LAN): – Nodes are within a small geographic region: Homes Schools Small businesses • Wide area network (WAN): – LANs connected over long distances: A few miles to thousands of miles Use telecommunications lines © 2006 Prentice-Hall, Inc. NEXT SLIDE 9 Technology In Action Chapter 7 Network Components • • • • Transmission media Network adapters Navigation devices Network software © 2006 Prentice-Hall, Inc. NEXT SLIDE 10 Technology In Action Chapter 7 Transmission Media • Provides communications channel between nodes • Forms of media: – Telephone wire: Twisted pair – Coaxial cable – Fiber-optic cable – Radio waves: Wireless • Bandwidth: – Data transfer rate, throughput © 2006 Prentice-Hall, Inc. NEXT SLIDE 11 Technology In Action Chapter 7 Network Adapters • Devices connected to or installed in nodes: – Network interface cards (NIC) – External network adapter • Enable communication between nodes NIC © 2006 Prentice-Hall, Inc. External adapter NEXT SLIDE 12 Technology In Action Chapter 7 Network Navigation Devices • Devices that help make data flow possible – Packets • Routers: – Route data between networks • Hubs: – Receive data and retransmit it to nodes on the network Router © 2006 Prentice-Hall, Inc. Hub NEXT SLIDE 13 Technology In Action Chapter 7 Networking Software • Software needed: – Peer-to-peer: Operating systems that support networking Windows Mac OS – Client/server: Network operating system (NOS) software Windows XP Professional Windows Server 2003 Novell Netware © 2006 Prentice-Hall, Inc. 14 Technology In Action Chapter 7 Types of Peer-to-Peer Networks • • • • Power line Phone line Ethernet Wireless © 2006 Prentice-Hall, Inc. 15 Technology In Action Chapter 7 Power Line Networks • Computers are connected to a house’s electrical wiring to create a network • Power line network adapter is used to connect nodes to electrical outlets © 2006 Prentice-Hall, Inc. NEXT SLIDE 16 Technology In Action Chapter 7 Phone Line Networks • Computers are connected to a house’s telephone wiring to create a network • Home phone line network adapter is used to connect nodes to phone jacks © 2006 Prentice-Hall, Inc. NEXT SLIDE 17 Technology In Action Chapter 7 Ethernet Networks • Computers are connected to each other using unshielded twisted pair cable (UTP) – Cat 5 (100Mbps), Cat 5E(200Mbps), Cat 6(1Gbps) • Ethernet network adapters are used to connect nodes NIC card – NIC – PC card – USB adapter © 2006 Prentice-Hall, Inc. PC card NEXT SLIDE 18 Technology In Action Chapter 7 Ethernet Hubs • Keep track of data packets • Amplify and retransmit signals • Keep the network running efficiently © 2006 Prentice-Hall, Inc. NEXT SLIDE 19 Technology In Action Chapter 7 Ethernet Routers • Route packets of data between networks • Router needed to send data between the network and the Internet © 2006 Prentice-Hall, Inc. NEXT SLIDE 20 Technology In Action Chapter 7 Wireless Networks • Use radio waves to connect nodes • 802.11 standard (Wi-Fi: Wireless Fidelity) – 802.11b (11Mbps), 802.11g(54Mbps) • Basically an Ethernet network that uses radio waves instead of wires • Each node requires a wireless network adapter: – Transceiver © 2006 Prentice-Hall, Inc. NEXT SLIDE 21 Technology In Action Chapter 7 Limitation • Maximum range: 250 feet • Interference with other wireless devices • Obstacles between wireless nodes – Wall – Large metal objects • Wireless DSL/cable router © 2006 Prentice-Hall, Inc. 22 Technology In Action Chapter 7 Choosing a Peer-to-Peer Network • Things to consider: – – – – Existing wiring Wireless or wired Speed of the network Cost of the network © 2006 Prentice-Hall, Inc. NEXT SLIDE 23 Technology In Action Chapter 7 Comparison © 2006 Prentice-Hall, Inc. 24 Technology In Action Chapter 7 Configuring Software for a Home Network • Windows operating system: – Windows XP: Network setup wizard – Windows ME: Network setup wizard – Windows 98: Configure manually © 2006 Prentice-Hall, Inc. NEXT SLIDE 25 Technology In Action Chapter 7 Computer Threats • Cyber-crime • Hackers: – Who they are – What they do – How they gain access © 2006 Prentice-Hall, Inc. NEXT SLIDE 26 Technology In Action Chapter 7 Cyber-crimes and Cyber-criminals • Cyber-crimes are criminal acts conducted through the use of a computer: – Fraud – Identity theft • Cyber-criminals are individuals who use a computer to commit a crime © 2006 Prentice-Hall, Inc. NEXT SLIDE 27 Technology In Action Chapter 7 Hackers • Anyone who unlawfully accesses a computer system • Types of hackers: – – – – Cracker White-hat Black-hat Script kiddies © 2006 Prentice-Hall, Inc. NEXT SLIDE 28 Technology In Action Chapter 7 What Hackers Do • Steal information from computers: – Credit card numbers – Bank account numbers • Internet packet sniffing • Commit identity theft • Create widespread computer attacks: – Backdoor programs (Trojan horse) – Zombies • Denial of service attacks (DoS) • Distributed denial of service (DDoS) attacks © 2006 Prentice-Hall, Inc. NEXT SLIDE 29 Technology In Action Chapter 7 How Hackers Gain Access • Direct access: – Hacking software • Indirect access: – Internet connection – Logical ports HTTP: 80 SMTP: 25 © 2006 Prentice-Hall, Inc. NEXT SLIDE 30 Technology In Action Chapter 7 Computer Safeguards • Firewalls • Viruses and antivirus software © 2006 Prentice-Hall, Inc. NEXT SLIDE 31 Technology In Action Chapter 7 Firewalls • Software programs or hardware designed to close logical ports to invaders • Types of firewalls: – – – – – Norton Personal Firewall McAfee Firewall Zone Alarm BlackICE PC Protection Network routers © 2006 Prentice-Hall, Inc. NEXT SLIDE 32 Technology In Action Chapter 7 Is your computer secure? • Gibson Research Corporation – www.grc.com – ShieldsUP – LeakTest • Qualys – http://browsercheck.qualys.com © 2006 Prentice-Hall, Inc. 33 Technology In Action Chapter 7 Chapter 7 Summary Questions • What is a network and what are the advantages of setting up one? • What is the difference between a client/server network and a peer-to-peer network? • What are the main components of every network? • What are the most common home networks? © 2006 Prentice-Hall, Inc. NEXT SLIDE 34 Technology In Action Chapter 7 Chapter 7 Summary Questions • • • • • What are power line networks? What are phone line networks? What are Ethernet networks? What are wireless networks? How can hackers attack a network and what harm can they cause? • What is a firewall and how does it keep my computer safe from hackers? © 2006 Prentice-Hall, Inc. NEXT SLIDE 35