A computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. The connections (network links) between nodes are established using either cable media or wireless media. The best-known computer network is the Internet.

1. Introduction
• Data Communication
• Networks
• Protocols and Standards
• Standard Organizations

2. Data Communication System Components

5. Basic Concepts
• Line Configuration
• Topology
• Transmission Mode
• Categories of Networks
• Internetworks

7. Point-to-Point Line Configuration

8. Point-to-Point Line Configuration

9. Point-to-Point Line Configuration

10. Multipoint Line Configuration

12. Mesh Topology

13. Star Topology

14. Tree Topology

15. Bus Topology

16. Ring Topology

18. Simplex

19. Half-Duplex

20. Full-Duplex

21. OSI
Model
• The model
• Functions of the layers

22. OSI Model

23. OSI Layers

24. An Exchange Using the OSI Model

25. Physical Layer

26. Data Link Layer

28. Data Link Layer Example

29. Network Layer

31. Transport Layer

32. Transport Layer Example

33. Transport Layer Example

34. Session Layer

35. Presentation Layer

36. Application Layer

37. Summary of Layer Functions

38. Transmission Media
• Guided Media
• Unguided Media

39. Electromagnetic Spectrum

42. Twisted-Pair Cable

43. Effect of Noise on Parallel Lines

44. Noise on Twisted-Pair Lines

45. Unshielded Twisted-Pair Cable

46. UTP Connectors

47. Shielded Twisted-Pair Cable

48. Coaxial Cable

49. Refraction

50. Critical Angle

51. Reflection

53. Multimode Step-Index

54. Multimode Graded-Index

55. Single Mode

56. Fiber Construction