Data Communications Lecture Notes

What is Data Communication?

• Definition: Exchange of data between two devices through some form of transmission medium.
  • Can occur between any two devices (e.g., mobile to mobile, computer to computer, mobile to computer).
• Data Forms: Text, audio, video, images, etc.
• Transmission Medium:
  • Wired: Using cables.
  • Wireless: Without physical cables.

Communication System

• Components: Combination of hardware and software.
• Importance: Devices must be part of a communication system for successful data communication.

Effectiveness of Data Communication System

• Four Fundamental Characteristics:
  1. Delivery: Data must reach the correct destination.
  2. Accuracy: Data should arrive without alteration.
  3. Timeliness: Data must be delivered in a timely manner, especially in real-time transmission.
  4. Jitter: Variation in packet arrival time should be minimized to avoid quality reduction in audio/video.

Components of Data Communication System

• Five Components:
  1. Message: The information/data to be communicated.
     • Forms: Text, audio, video, images, etc.
  2. Sender: The device that sends the data (e.g., computer, camera, mobile).
  3. Receiver: The device that receives the data (e.g., computer, mobile, TV).
  4. Transmission Medium: The physical path for data travel (e.g., cables, radio waves).
  5. Protocol: Set of rules governing data communication.
     • Importance: Represents an agreement between communicating devices.
     • Example: If devices use different languages without a common protocol, communication fails.

Conclusion

• Successful data communication relies on proper use of transmission mediums and protocols.
• Ensure that all components are functioning and properly aligned for effective data exchange.