Data Communication

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What is Data Communications?
Data Communications is the exchange of data between two devices via some form of transmission medium such as wire cable.

An effective data communications has 3 characteristics:



  1. Delivery
    • Correct destination
    • Receive by the intended device or user
  2. Accuracy
    • Deliver data accurately
    • Altered data unusable
  3. Timeliness
    • Deliver data in a timely manner
    • Real time transmission – deliver data as they are produced, in the same order that they are produced, without delay.
Data Communication Network Criteria

  • Performance
    • Measured by transit time (amount of time required for a message to travel from one device to another ).
    • Measured by response time (elapsed time between inquiry and a response).
    • No. of users, type of transmission medium, hardware’s capabilities, software’s efficiency.
  • Reliability
      • Measured by frequency of failure, time taken to recover, network’s robustness in catastrophe.
  • Security
    • Protect data from unauthorized access

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