Types of Communication Flashcards
What is data transmission?
- the transfer of data between two or more digital devices.
What is serial data transmission?
- is where data is transmitted one bit at a time along a single data cable.
What is parallel data transmission?
- where data is transmitted more than one bit at a time along separate data cables.
What is the difference between serial data transmission and parallel data transmission?
- Serial data transmission sends bits in sequence
- Parallel data transmission sends bits all together.
What are some advantages of serial data transmission?
- It can cover longer distances
- requires fewer channels/wires to transmit data
- cheaper
what are features of serial data transmission?
- Serial data cable includes the USB (Universal Serial Bus)
- They have more wires for the control signals
- A PC has several USB ports for connecting peripherals
- they are reliable over shorter distances
- faster when transmitting data
Which is better in speed? Serial or parallel?
- If a parallel data bus had eight cables it would, in theory, transmit data eight times faster than the single data cable used in a serial bus.
Which is better of interference? Serial or parallel?
- There is interference between the parallel wires which reduces the bandwidth of parallel connections, so parallel transmission bit rate is limited by interference.
What are connections like in serial and parallel?
- Connecting cables are short to minimise the interference effect with parallel transmission, whereas in the serial connection there is no interference or noise problem so connecting cables can be as long as 300 feet
Which one uses more cables? Serial or Parallel?
Parallel data transmission uses more cables than serial data transmission: therefore, they are larger, more expensive to produce and more complex than serial cables.
What are the advantages and disadvantages of serial data transmission?
- Cheaper (only one wire needed)
- For two way communication an
extra wire needed - Reliable but slow
- Serial transmissions is reliable over very long distances at very high frequencies
- Serial connectors such as USB connectors are much smaller and cheaper than parallel connectors
What are the advantages and disadvantages of parallel data transmission?
- For two way communication, twice the number of lines are required
- Data is sent faster
- If data is sent in the wrong format, it has to be sent faster
- As speeds of transmission got higher and higher, parallel connection developed problems.
- Parallel transmission can be used only very short distance distances of up to about 2m
What are the two types of data transmission?
- skew
- crosstalk
What is skew data transmission?
- happens when the bits that are transmitted across parallel links travel at different speeds.
- Data can fall out of sync with the clock signal and therefore not being read correctly.
What is Cross talk data transmission?
- occurs when electromagnetic interference between wires that are in proximity results in transmitting corrupted data that needs to be resent.