Observe Yourself or -5

1. Observe Yourself or -5 • Turn off communication devices Dress properly

2. Module 7 Communication

3. Learning Objectives You will be able to: • Describe purposes of network. • Discuss various ways of network application. • Explain types of communications media. • Describe how data travels over a network. • List and explain functions for several types of networking hardware.

4. Topics • Communication Application • Analog VS Digital Signal • Communication Channel • Wire: • Twisted-Pair cable • Coaxial cable • Fiber Optic cable • Short-range wireless • Long-range wireless • Wireless: • Infrared • Microwave • Satellite • Cellular

5. What is Communication? • Communication is the transmission of data or information over the media from a sender to the receiver. • Telecommunication is a communication over long distance.

6. Telecommunication is not new. • We had data, voice, motion picture communication for century.

7. Telecommunication in the Past • Telegraph • Radio • Telephone • Television

8. Telegram • Telegraph was born around year 1800. • In Thailand, it was born in King Rama V • 1 May 2008, telegram service in Thailand became history for 133 years. • Because there are just 100 private users of telegram service per month. • It is not worth to maintain the system using 300 million bath yearly for earning only 5 million baht a year.

9. Communication Applications

10. Various Communication Application One-way Voice Communication Two-way Voice Communication Data Communication MMS Paging Messaging Satellite Radio Satellite Phone

11. Videophone • A videophone is a telephone with a video screen, and is capable of full duplex (bi-directional) video and audio transmissions for communication between people in real-time. FaceTime by Apple

12. Videoconferencing • Videoconferencing • the use of television video and sound technology as well as computers to enable people in different locations to conduct real-time, face-to-face meetings. • In addition to audio and video, online conferencing typically includes other sharing options, such as a shared electronic whiteboard or workspace so that documents and suggested modifications can be viewed by all participants.

13. Collaborative Computing • Another way of collaborating with others using a computer and communications technology is using collaborative software tools to work together on documents and other project components • Often called workgroup computing or collaborative computing.

14. Collaborative Software • Groupware • Software that allows two or more people on a network to work on the same information at the same time. • Examples: • Lotus Notes • SharePoint

15. Telecommuting • Commuting means regular travel between residence and work place. • Most workers travel at the same time in the morning and evening causing traffic congestion.

16. Telecommuting, Telework, eWork • The Internet, e-mail, videoconferencing, mobile phones, and collaborative computing have made telecommuting a viable option for some. • With telecommuting, individuals work at home and communicate with their place of business and clients via communications technologies.

17. Anywhere At Park At Beach At Cafe On Sofa On Bed At Home

18. Telecommuting Benefits • No time wasted in commuting. No stress in traffic jam.No commuting time means increased time available for work. • Flexible scheduleEmployees can work at their peak times because of flexible schedules which will produce more work or greater productivity. • Lower costs to the company because of less office space, furnishings, and costs. • Greater balance between work and family life.

19. Telecommuting Drawbacks • Feeling of isolation. • Uncontrollable himself that may cause less productivity.

20. Telemedicine

21. Telesurgery Da Vinci surgical robot

22. Benefits • In general, telemedicine has enormous potential for providing quality care to individuals who live in rural or underdeveloped areas and who do not have access to sufficient medical care. • Telemedicine will also be necessary for future long-term space explorations such as a trip to Mars • since astronauts will undoubtedly need medical care while on the journey.

23. End: Communication Application

24. How data travel over communication system

25. Analog & Digital

26. Analog & Digital Telephone

27. Analog & Digital TV

28. What is Analog? • Analog refers to

29. Analog Devices Tire-pressure gauge Speedometer Thermometer

30. Digital Signal • , expressed as discrete bursts in on/off electrical pulses. • Communications signals or information represented in a two-state (binary) way

31. Light Switch • On and off have two states • In dimmer switch, the changes in this signal are gradual which gradually increases or decreases brightness

32. Why change analog to digital? • Why bother to change analog signals into digital ones, especially since the digital representations are only approximations of analog events? • The reason is that digital signals are easier to store and manipulate.

33. Laser 0 0 1 1 1 Data Storage • Any media that can represent 2 states, can store digital data.

34. Error Correction • Digital is easy to detect and correct.

35. Transmit digital data over telephone • Telephone lines have traditionally been analog. • What is used for your computer to communicate over telephone line?

36. Use of Modem

37. Two Characteristics of Electrical Signal • : Number of times a wave repeats during a specific time interval. • : The height of a wave within a given period of time.

38. Characteristics of Analog Signal high frequency low frequency low amplitude high amplitude

39. Communication media (Channels)

40. Communication channel is the medium or path which information travels in communication system from its source to its destination.

41. Types of Communication Media • Wire • Wireless http://blogs.voices.com/voxdaily/2008/01/high_school_broadcasting.html

42. Wired Communication Twisted-Pair Wire Coaxial Cable Fiber-Optic Cable

43. Twisted-Pair Wire • Consists of pairs of thin strands of insulated wire twisted together • It is the same type of cabling that is found inside the walls of most homes for telephone communications. • Twisted-pair cable is rated by category such as category 1, 2, 3, 4, 5, 5e, 6, 6a.

44. Coaxial Cable • Consists of insulated copper wire wrapped in a solid or braided metal shield, then in and external plastic cover. • More static from noise than twisted-pair wire. • Used for Cable TV.

45. Fiber-Optic Cable • Consists of dozens or hundreds of thin strands of glass or plastic that transmit pulsating _____________rather than electricity. • Unaffected by _________________________ • It cannot easily be _________, so transmissions are more ____________. • It is commonly used for the high-speed backbone lines of network. http://static.howstuffworks.com/gif/fiber-optic-fiber.jpg

46. Wireless communication

47. Wireless communication is the transfer of information over a distance without the use of electrical conductors or “wires”. Instead it uses electromagnetic waves to carry a signal over communication path. http://blogs.voices.com/voxdaily/2008/01/high_school_broadcasting.html

48. L L/2 sec 0 1 The Electromagnetic Spectrum • Electromagnetic waves vary according to frequency: • Frequency • The number of times a wave repeats, or makes a cycle, in a second. • Is measured in hertz (Hz) • 1 Hz equal to 1 cycle per second.

49. The Radio Spectrum

50. Electromagnetic Wave Regulator • In US, • Federal Communications Commission (FCC) • In Thai, • The National Broadcasting and Telecommunications Commission (NBTC)คณะกรรมการกิจการกระจายเสียง กิจการโทรทัศน์ และกิจการโทรคมนาคมแห่งชาติ (กสทช.) • National Telecommunications Commission (NTC) คณะกรรมการกิจการโทรคมนาคมแห่งชาติ(กทช.)