What does CSMA/CD stand for?

CSMA/CD stands for carrier sense multiple access with collision detection. Wired Ethernet uses CSMA/CD on shared media.

Describe how CSMA/CD works.

A device listens for a carrier and transmits only when the line is quiet. The device keeps listening while sending and stops at once if a collision is detected.

What happens immediately after a collision is detected?

The transmitting device sends a short jam signal so every device knows a collision occurred. All transmitting devices then abandon their frames.

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Data Transmission and Network Performance

Network collisions and collision detection

3 things to know
Component 2

Overview

Network collision, collision domain and how CSMA/CD works.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

What is a network collision?

Key term

What is a collision domain?

Key term

Why do collisions happen on a bus network?

Questions from this subtopic

Each one with the model answer underneath.

1
What is a network collision?
Model answer
A collision occurs when two devices transmit on a shared medium at the same moment. The signals overlap and both frames are corrupted.
2
What is a collision domain?
Model answer
A collision domain is the set of devices whose transmissions can collide with one another. Every port on a hub belongs to one collision domain.
3
Why do collisions happen on a bus network?
Model answer
Every device on a bus shares one cable and may start sending at any moment. Two devices that both find the line quiet can begin together.
4
What does CSMA/CD stand for?
Model answer
CSMA/CD stands for carrier sense multiple access with collision detection. Wired Ethernet uses CSMA/CD on shared media.
5
Describe how CSMA/CD works.
Model answer
A device listens for a carrier and transmits only when the line is quiet. The device keeps listening while sending and stops at once if a collision is detected.
6
What happens immediately after a collision is detected?
Model answer
The transmitting device sends a short jam signal so every device knows a collision occurred. All transmitting devices then abandon their frames.

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