Ch2 Data Transmission

Question 1

Packet Switching

Answer 1

-Method of data transmission where the data is broken into multiple packets. Packets are then independently sent from start to end and reassembled at the recievers computer.

Question 2

Advantages of packet switching

Answer 2

-No need to create a single line of communication
-High data transmission speed
- Easy to expand package usage
-possible to overcome failed or busy lines by simply re-routing packets

Question 3

Disadvantages of packet switching

Answer 3

-The packets can be lost and need to be resent
- the method is more prone to errors with real-time streaming
-there is a delay at the destination whilst the packets are being re-ordered

Question 4

Simplex data transmission

Answer 4

when data can be sent in one direction only (computer to a printer)

Question 5

Half-Duplex data transmission

Answer 5

when data can be sent in both directions but not at the same time (walkie-talkie)

Question 6

Full-Duplex data transmission

Answer 6

when data can be sent in both directions at the same time (broaddband internet connection)

Question 7

Serial and Parrallel data transmission comparison

Answer 7

Parallel:
-Better for shorter distances like the internal circuits in a computer\
-Faster data transmission
-Used when speed is neccesary
-more expensive due to more hardware
-can arrive skewed(unsynchronised)

Serial:
-Better for longer distances like telephone lines
-Cheaper option
-Used when the size of data transmitted is small
-Slower option
-less external interference due to fewer wires

Question 8

USB

Answer 8

-The universal Serial Bus is an asynchronous serial data transmission.
-allows half duplex and full duplex data transmission

Question 9

Benefits and Drawbacks of using a USB

Answer 9

Benefits:
-devices plugged into the Computers are automatially deteced
-connections only fit one way preventing incorrect connections
-can support different data transmission rates
-backwards compatible (older versions are still supported)
-it has become an industry standard which means considerable support is available

Drawbacks:
-Maximum cable length supported by the USB is 5 about meters
-Transmission rate is less than 120 mb/sec
-very ear;y USB standards may not always be supported by the latest computers

Question 10

Errors can occur during data transmission due to:

Answer 10

-Interference(electfical interference which can cause data to be corrupted)
-problems during packet switiching like data loss
-Skewing of data (occurs during parrallel data transmissiona dn can cause data corruption