1. Chapter 6 The Internet

2. 6 Chapter 6: The Internet 2 Chapter Contents  Section A: Internet Technology  Section B: Fixed Internet Access  Section C: Portable and Mobile Internet Access  Section D: Internet Services  Section E: Internet Security

3. 6 SECTION A Chapter 6: The Internet 3 Internet Technology  Background  Internet Infrastructure  Internet Protocols, Addresses, and Domains  Connection Speed

4. 6 Chapter 6: The Internet 4 Background  The ARPANET, created in 1969, connected computers at UCLA, Stanford Research Institute, University of Utah, and University of California at Santa Barbara  Today, the Internet connects computers all over the globe and supplies information to people of all ages and interests  With an estimated 500 million nodes and more than 1 billion users, the Internet is huge

5. 6 Chapter 6: The Internet 5 Internet Infrastructure  The Internet is not owned or operated by any single corporation or government  The Internet backbone is a network of high-capacity communications links that provides the main routes for data traffic across the Internet  Backbone links and routers are maintained by network service providers (NSPs)  NSP equipment and links are tied together by network access points (NAPs)  An Internet service provider (ISP) is a company that offers Internet access to individuals, businesses, and smaller ISPs

6. 6 Chapter 6: The Internet 6 Internet Infrastructure

7. 6 Chapter 6: The Internet 7 Internet Infrastructure  To communicate with an ISP, your computer uses some type of communications device, such as a modem

8. 6 Internet Protocols, Addresses, and Domains Chapter 6: The Internet 8

9. 6 Internet Protocols, Addresses, and Domains  A computer can have a permanently assigned static IP address or a temporarily assigned dynamic IP address Chapter 6: The Internet 9

10. 6 Internet Protocols, Addresses, and Domains Chapter 6: The Internet 10

11. 6 Chapter 6: The Internet 11 Internet Protocols, Addresses, and Domains The first step in registering a domain name is to find out whether the name is currently in use or reserved for future use. If a domain name is not available, consider using a different top-level domain, such as biz instead of com. After you’ve found an available domain name, you can continue the registration process by filling out a simple online form.

12. 6 Chapter 6: The Internet 12 Connection Speed  Data travels over the Internet at an incredible speed  The elapsed time for data to make a round trip from point A to point B and back to point A is referred to as latency –Ping –Traceroute tracert  Upstream vs. downstream speed

13. 6 SECTION B Chapter 6: The Internet 13 Fixed Internet Access  Dial-up Connections  DSL, ISDN, and Dedicated Lines  Cable Internet Service  Satellite Internet Service

14. 6 Chapter 6: The Internet 14 Dial-up Connections  A dial-up connection is a fixed Internet connection that uses a voiceband modem and telephone lines to transport data between your computer and your ISP

15. 6 Chapter 6: The Internet 15 Dial-up Connections  A voiceband modem converts the signals from your computer into signals that can travel over telephone lines  Modem speed is measured in bits per second

16. 6 Chapter 6: The Internet 16 DSL, ISDN, and Dedicated Lines  T1, T3, and T4 lines are leased from the telephone company and offer fast, high-capacity data transmission  ISDN (Integrated Services Digital Network) is a type of fixed Internet connection that moves data at speeds of 64 Kbps or 128 Kbps over ordinary telephone lines –ISDN terminal adapter connects a computer to a telephone wall jack and converts signals to travel over ISDN connection

17. 6 Chapter 6: The Internet 17 DSL, ISDN, and Dedicated Lines  DSL is a high-speed, digital, always-on Internet access technology that runs over standard phone lines –Some DSL installations require service technicians DSL modem

18. 6 Chapter 6: The Internet 18 Cable Internet Service  Cable Internet service distributes always-on, broadband Internet access over the same infrastructure that offers cable television service

19. 6 Chapter 6: The Internet 19 Cable Internet Service  Cable modems convert your computer’s signal into one that can travel over the CATV network  Always-on connection  DOCSIS-compliant cable modems

20. 6 Chapter 6: The Internet 20 Satellite Internet Service  Satellite Internet service distributes always-on, high-speed asymmetric Internet access by broadcasting signals to and from a personal satellite dish  A satellite modem is a device that modulates data signals from a computer into a frequency band that can be carried to the satellite dish where it is converted to another frequency, amplified, and transmitted

21. 6 Chapter 6: The Internet 21 Satellite Internet Service

22. 6 Chapter 6: The Internet 22 Fixed Wireless Service  Fixed wireless Internet service broadcasts signals in order to offer Internet access to large areas –WiMAX –A WiMAX system transmits data to and from WiMAX antennas mounted on towers –Under ideal conditions, WiMAX can transmit data at 70 Mbps

23. 6 Fixed Internet Connection Roundup Chapter 6: The Internet 23

24. 6 SECTION C Chapter 6: The Internet 24 Portable and Mobile Internet Access  Internet to Go  Wi-Fi Hotspots  Portable and Mobile WiMAX  Portable Satellite Service  Cellular Data Service

25. 6 Chapter 6: The Internet 25 Wi-Fi Hotspots  A Wi-Fi hotspot is an area in which the public can access a Wi-Fi network that offers Internet service  Wi-Fi does not typically provide acceptable mobile Internet access because you can only remain connected within range of the network’s hotspot

26. 6 Chapter 6: The Internet 26 Portable Satellite Service

27. 6 Chapter 6: The Internet 27 Cellular Data Services  Using cellular phone technology to access the Internet offers mobility that is not yet possible with most of today’s wired or wireless computer network technologies

28. 6 Chapter 6: The Internet 28 Cellular Data Services  The fastest cellular technologies for Internet access are EDGE, EV-DO, and HSUPA  Most cellular service providers offer a data service plan for accessing the Internet  You can use a smart phone or cellular- ready PDA to access the Internet by subscribing to a data service plan offered by a mobile phone provider such as AT&T or Sprint

29. 6 SECTION D Chapter 6: The Internet 29 Internet Services  Real-Time Messaging  Voice over IP  Grid Computing  FTP  File sharing

30. 6 Chapter 6: The Internet 30 Real-Time Messaging  A networked-based, real-time messaging system allows people to exchange short messages while they are online –Instant messaging (IM) –Chat

31. 6 Chapter 6: The Internet 31 Voice over IP  VoIP (Voice over Internet Protocol) or Voice over IP, is a technology in which a broadband Internet connection is used to place telephone calls instead of the regular phone system  To set up a standard VoIP system, you can use an inexpensive ATA, IP phone, wireless IP phone, or USB phone

32. 6 Chapter 6: The Internet 32 Voice over IP  Advantages –Low cost –Flexibility –Phone number moves with you  Disadvantages –Quality can vary –Must have power to work

33. 6 Chapter 6: The Internet 33 Grid Computing  A grid computing system is a network of computers harnessed together to perform processing tasks  SETI@home project

34. 6 Chapter 6: The Internet 34 FTP

35. 6 Chapter 6: The Internet 35 FTP

36. 6 Chapter 6: The Internet 36 File Sharing  P2P file sharing uses peer- to-peer (P2P) protocols that allow users to obtain files from other users located anywhere on the Internet  BitTorrent is a file sharing protocol that distributes the role of file server across a collection of dispersed computers

37. 6 SECTION E Chapter 6: The Internet 37 Internet Security  Intrusion Attempts  Securing Ports  Routers and NAT  Virtual Private Networks

38. 6 Chapter 6: The Internet 38 Intrusion Attempts  An intrusion is any access to data or programs by hackers, criminals, or other unauthorized persons  Looking for open ports is one of the most common ways of gaining unauthorized access to a network-based computer  A port probe (or port scan) uses automated software to locate computers that have open ports and are vulnerable to unauthorized access

39. 6 Chapter 6: The Internet 39 Intrusion Attempts

40. 6 Chapter 6: The Internet 40 Securing Ports  One of the easiest steps to enhance your computer’s security is to turn it off when you aren’t using it  A firewall is software or hardware designed to filter out suspicious packets attempting to enter or leave a computer

41. 6 Chapter 6: The Internet 41 Securing Ports

42. 6 Chapter 6: The Internet 42 Routers and NAT  Routers are intended to work on LANs to monitor and direct packets being transported from one device to another  A routable IP address is one that can be accessed by packets on the Internet  A private IP address is a non-routable IP address that can be used within a LAN, but not for Internet data transport

43. 6 Chapter 6: The Internet 43 Routers and NAT

44. 6 Chapter 6: The Internet 44 Routers and NAT  Network address translation (NAT) is the process your router uses to keep track of packets and their corresponding private or public IP addresses

45. 6 Chapter 6: The Internet 45 Virtual Private Networks  It is possible to secure remote connections by setting up virtual private network (VPN) access to a remote access server in the corporate office  Access to a VPN is usually by invitation only. Employees who need to access a VPN are given the necessary instructions, addresses, and passwords to make connections

46. 6 Chapter 6: The Internet 46 Virtual Private Networks

47. Chapter 6 Complete The Internet