JSS 2 WEEK FOUR LESSON NOTE (ICT_323)

 



Jss2

TOPIC: DATA   COMMUNICATION

Introduction  

The physical connection between networked computing devices is established using either cable media or wireless media.

Data communication

Data communication refers to the exchange of data between a source and a receiver via a form of transmission media such as a wire cable. Data communication is said to be local if communicating devices are in the same building or a similar restricted geographical area.

Components of Data System

1.     Message: it is the information or data to be communicated. It can consist of text, numbers, pictures, sound or video or any combination of these.

2.     Sender: it is the device/ computer that generates and sends that message

3.     Receiver: it is the device or computer that receives the message. The location of receiver computer is generally different from the sender computer.

4.     medium: it is the channel or physical path through which the message is carried from sender to the receiver

5.     Protocol: it is set of rules that govern the communication between the devices. Both sender and receiver follow same protocols to communicate with each other.

FUNDAMENTAL CHARACTERISTICS

1.     Delivery:  the data must be delivered in the correct order with correct destination.

2.     Accuracy: the data must be delivered accurately.

3.     Timeliness: the data must be delivered in a timely manner. Late delivered data is useless.

4.     Jitter: it is the uneven delay in the packet arrival time that cause uneven quality.

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