Page 51 - Handout Computer Network.
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It ensures that important or real-time applications receive better network performance compared to
less critical traffic.
QoS is especially important in networks that carry:
• Voice
• Video
• Real-time data
• Multimedia services
Why QoS is Important
In a network, many devices send data at the same time. This may cause problems such as:
• Delay (Latency) – time taken for data to travel from source to destination
• Jitter – variation in delay between packets
• Packet Loss – data packets lost during transmission
• Congestion – too much traffic in the network
QoS helps control these problems and ensures that critical applications work properly.
Example:
A video call needs low delay and low packet loss, otherwise the video will freeze or break.
2.12 QoS Performance Parameters
QoS is usually measured using several key parameters.
2.12 1Bandwidth
The amount of data that can be transmitted over a network in a given time.
Higher bandwidth allows more data to be sent.
Example:
100 Mbps network has more bandwidth than 10 Mbps.
2. Latency (Delay)
Latency is the time required for a packet to travel from the sender to the receiver.
Lower latency is important for:
• Voice calls
• Online gaming
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