Chapter 4 Telecommunications and the Internet

1. Chapter 4Telecommunications and the Internet Dr. Hassan Ismail

2. Chapter 4 Objectives • Understand the role of telecommunications in organizations • Understand the evolution of computer networks • Understand the Internet and how it works • Understand basic Internet services • Understand the use of the World Wide Web

3. The Role of Telecommunicationsand Networks in Organizations • Definitions • Telecommunications – the transmission of all forms of information, including digital data, voice, fax, sound, and video, from one location to another over some type of network • Network– a group of computers and associated peripheral devices connected by a communication channel capable of sharing information and other resources (e.g., like a printer) between users • Bandwidth – the carrying capacity of telecommunications networks

4. The Role of Telecommunicationsand Networks in Organizations • Interpersonal Communication Applications • E-mail and Groupware • Voice mail & Facsimile (fax) • Teleconferencing, Data conferencing and Videoconferencing • Common business applications: • Distance learning, • E-learning • E-commerce • E-business • Telemedicine

5. Electronic Mail and Groupware • E-mail: Eliminates telephone tag and costly long-distance telephone charges • Groupware: Enables work groups at different locations to participate in discussion forums and work on shared documents and projects

6. Voice Mail and Fax • Voice mail: Digitizes spoken message and transmits it over a network • Fax: Digitizes and transmits documents over telephone lines

7. Teleconferencing, data conferencing, and videoconferencing • Teleconferencing: Ability to confer with a group of people simultaneously • Data conferencing: Two or more users can edit and modify data files simultaneously • Videoconferencing: Participants are able to see each other over video screens

8. Common business applications • Distance learning: Education or training delivered over a distance to individuals in one or more locations • E-learning: Instruction delivered online using the Internet or private networks • E-Commerce: buying or selling online online using the Internet or private networks • E-business: use the internet technology to support business. • Telemedicine: exchange of medical information from one location to another via a computer network.

9. Network Topologies • Star network • Ring network • Bus network

10. Bus Topology

11. Ring Topology

12. Star topology

13. Evolution of Computer Networking • Sharing Information • Senders and receivers that have something to share • Transmission media: cable to send the message • Rules or protocols: dictating communication between senders and receivers.

14. Evolution of Computer Networking • Computer Networks: 1) Digitizing => 2) Modem

15. Evolution of Computer Networking • Centralized Computing: large centralized computer called mainframe were used to process and store data Mainframe

16. Evolution of Computer Networking Distributed Computing: multiple types of computers are networked together to share information and services

17. Evolution of Computer Networking Collaborative Computing: two or more networked computers are used to accomplish a common processing task. (1) (2) (3) 1. Requests record to change 3. Returns changed record 2. Returns requested record

18. Evolution of Computer Networking • Types of Networks • Private Branch Exchange (PBX) • Local Area Network (LAN) • Wide Area Network (WAN) • Personal Area Networks (PANs):

19. Evolution of Computer Networking • Types of Networks • Private Branch Exchange (PBX): • Central switching system • Handle firm’s voice and digital communications

20. Evolution of Computer Networking Local Area Network (LAN): • Telecommunication network • Require its own dedicated channels • Encompass a limited distance • Gateway, router, Network Operating System (NOS)

21. Wide Area Networks (WANs) • Telecommunication network • Span large geographical distance • Consist of variety of cable, satellite, and microwave technologies • Switched lines, dedicated lines

22. …WAN types • Global Networks: spans multiple countries and may include several organizations • Enterprise Networks: WAN connecting networks of single organization • Value-Added Networks (VANs): private, third-party managed networks (lease communication lines rather than investing in dedicated network equipment). • Metropolitan Area Networks (MANs): network for city-wide area

23. Wide Area Networks (WANs) • Telecommunication network • Span large geographical distance • Consist of variety of cable, satellite, and microwave technologies • Switched lines, dedicated lines

24. Personal Area Networks (PAN) emerging technology uses wireless communication to exchange data through short-range radio communication for short-distance (exp: Bluetooth)

25. The Internet • How did the Internet Get Started? • ARPANET • U.S. Defense • Advanced Research Projects Agency (ARPA) • NSFNET • National Science Foundation

26. The Internet • Internet Technologies • Packet-Switching Technology • TCP/IP • Transmission Control Protocol/Internet Protocol • IP Datagram • Connecting Independent Networks • Routers • Backbone Network

27. Packet switching

28. The Internet • Web Domain Names and Addresses • Uniform Resource Locator (URL) • Common domain extensions • .edu .org .mil .com .net • .ca .th .no (country codes) • IP Addresses

29. The Internet • Who Manages the Internet? • Domain Name System (DNS)– a system used to associate Internet host names with their Internet IP addresses • The Internet Registry–provides central maintenance of the DNS root database, used to associated Internet hostnames with their IP addresses.

30. The Internet • Who Manages the Internet? • Internet Corporation for Assigned Names and Numbers (ICANN)– a non-profit corporation manages IP addresses, domain names, and root server system management • InterNIC Registration Service– assigns Internet addresses

31. The Internet • How Do You connect to the Internet? • Internet Service Providers (ISPs): which will give you username and password to access to the internet. • Network Access Points (NAPs): within which ISPs can connect to one another. • Internet backbone: which is the collection of main network connections and telecommunications lines comprising the Internet.

32. The Internet • How Fast Is Your Connection? • Plain Old Telephone Service (POTS) • Integrated Services Digital Network (ISDN) • Digital Subsciber Line (DSL) • Cable Modems • Satellite Connections • T1 Lines • Asynchronous Transfer Mode (ATM)

33. The Internet • Security in the Internet Age • Encryption • Firewalls • Authentication

34. The Internet • State of the Internet • What are people doing on the Internet? • E-mail • What next for the Internet? • Internet2 • Abilene network backbone

36. The Internet • Internet Tools (see table in page 119) • E-mail • Telnet • File transfer • Listserv • Usenet • Archie • WAIS • Gopher • Voice over IP

37. World Wide Web • Web browser • Hypertext • Hyperlinks • Hypertext Markup Language (HTML) • Web servers • Hypertext Transfer Protocol (HTTP) • Uniform Resource Locator (URL)

38. World Wide Web • World Wide Web Architecture • World Wide Web Applications • Electronic brochure • Online ordering • Electronic marketplaces • Online customer service