Communications involve the exchange of data between two devices via transmission. There are protocols with rules that govern message transmission through a medium to be received. For effective communication, a system must deliver data to the correct destination accurately and in a timely manner without delay or jitter in packet arrival times. Communication systems can operate in simplex, half-duplex, or duplex modes depending on whether transmission is one-way, two-way but alternating, or two-way concurrently, respectively.

1.  Data
Communications are the exchange of
data between two devices via some form
of transmission.
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2. Protocol
Rules
.
.
.
Protocol
Rules
.
.
.
Message
Transmission Medium
Receiver
Sender
Data Communication and Computer Networks 1303330
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3. 1. Delivery: The system must deliver data to the correct
destination.
2. Accuracy:


Data delivered accurately.
Altered data which left uncorrected are unusable.
3. Timelines:
The system must deliver data in timely manner without
delay (real-time).
4. Jitter:
Jitter refers to the variation in the packet arrival
time. It is the uneven delay in the delivery of
audio or video packets.
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4.  Simplex:
one direction only.
Remote Control
TV
 Always
one side sender and another side
receiver.
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5.  Half-Duplex:
two-way alternate.
Walki-Talki
In different time
 Each
side maybe sender or receiver but not a
same time.
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6.  Duplex:
two-way concurrent.
Computer network
At same time
Mobile Network
 Each
side sender and receiver at same time.
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7.  Thank
You !!!