14.2 Circuit switching, packet switching

Question 1

What is circuit switching?

Answer 1

• A dedicated circuit is established at the start of communication.
• Between sender and reciever.
• Lasts for duration of communication.
• Then links that make up circuit removed.

Question 2

Benefits of circuit switching.

Answer 2

• Dedicated channel / can use all bandwidth
• Data arrives in order it is sent.
• Faster data transfer rate than packet switching
• Works better in real time applications.

Question 3

What is packet switching?

Answer 3

• Circuit does not have established at the start of communication.
• Data sent is divided into packets.
• Can travel along different routes.
• From node to node.
• Packets reassembled in correct order at destination.

Question 4

Benefits of packet switching.

Answer 4

• Possible to overcome faulty lines by re-routing packets.
• No need to tie up a communication line.
• Easy to expand the traffic usage.
• High data transmission possible with packet switching.

Question 5

Drawbacks of circuit switching.

Answer 5

• No alternative route if circuit is broken.
• No-one else can use the channel even if it is idle.
• Time taken to establish link may be long.