1.3 Data Transmission Flashcards
What are the two types of transmission?
- Serial transmission
- Parallel transmission
What is serial transmission?
Data sent bit-by-bit along the same data line.
What is parallel transmission?
All bits in bytes are sent simultaneously along separate data lines.
State 4 advantages for serial transmission.
- Cheaper and easier to setup.
- Requires only two wires rather than 8 or 16.
- Less prone to interference over long distances
- Simpler interface/circuit board.
State a disadvantage for serial transmission.
Only one bit can be transmitted at a time so transmission times can be longer.
State an advantage for parallel transmission.
Transmission can be completed in a shorter time (faster).
State 2 disadvantages for parallel transmission.
- Hardware is more expensive.
- Prone to interference over a long distance.
State 3 mode of transmission.
- Simplex
- Half-duplex
- Full-duplex
Explain simplex.
Data can travel in one direction e.g. radio.
Explain half-duplex.
Data can travel in both directions but not at the same time e.g. walkie talkie.
Explain full-duplex.
Data can travel in both directions at the same time e.g. phone.
What is multiplexing?
Allows multiple signal sources to send data along the same communication medium/wire.
What is switching?
A device forwards a packet of data towards their destination via a range of devices. It goes one step at a time to its destination.
State 7 things that a packet contains.
- Length
- Packet ID
- Source Address
- Destination Address
- Protocol
- Data
- Checksum
Explain Length.
Number of bits in the packet.