Data communication is the exchange of data between two drives via some form of transmission medium such as wire cable. The effectiveness of data communication system depends on fundamental characteristics:
- Delivery – the system must deliver data to the correct destination. Data must be received by the intended device or user and only be that devices or user.
- Accuracy – The system must deliver data accurately. Data that has been altered in transmission and left uncorrected is unusable.
- Timeliness – The system must deliver data in timely manner, data delivered late is useless. In case of video and audio timely delivery means delivering data as they are produced, in the same order that they are produced and without significant delay. This kind of delivery is called real time transmission.
- Jitter – Jitter refers to the variation in packet arrival time. It is the uneven delay in the delivery of the audios or video packets e.g. let us assume that video packers are sent every 30 milliseconds. If some of the packets arrive with 40 milliseconds delay, an uneven quality on the video is the result.