U14 communication and network tech Circuits and Packets

Question 1

packet switching

Answer 1

• a circuit does not have to be established at the start of communication
• data to be sent is divided into packets
• can travel different routes
• from node to node
• packets are reassembled in the correct order at the receiver’s end
• must wait until the last packet is received to put the data back together

Question 2

circuit switching

Answer 2

• dedicated communications channel b/w 2 communicating devices
• a circuit is established at the start of the communication
• between sender and receiver
• lasts for the duration of the call/data transfer
• the link that makes up the circuit is then removed

Question 3

packet switching pros

Answer 3

• packets can be re-routed if there are problems
• packets can take the least congested route
• transmission error can be detected
• missing packets can be resent

Question 4

packet switching cons

Answer 4

• packets can be delayed
• a real time conversation is not possible

Question 5

pros of circuit switching

Answer 5

• person communicating can see each other in real time
• better synchronization // full bandwidth available

Question 6

command

Answer 6

ensures that user can send instructions such as delete, copy which are carried out on the server

Question 7

anonymous

Answer 7

allows user to access files and user does not need to identify themselves to the server

Question 8

server

Answer 8

central computer that stores all files to be downloaded

Question 9

cons of circuit switching

Answer 9

• bandwidth // channel not available to other users
• extra time required to set up circuit at start of conversation
• alternative route not available without restarting the conversation
• less secure as easier to intercept data if only one channel is used
• failure in single route used means failure of transmission