data transmission Flashcards
Simplex data transmission
Data transmitted one way only; E.g. Computer to Printer
Duplex data transmission
Data transmitted both ways simultaneously; E.g. skype(VOIP)
Full-duplex data transmission
Data transmitted both ways at the same time
Half-duplex data transmission
Data transmitted both ways but not at the same time;
Serial data transmission
One bit sent at a time over single wire; E.g. Computer to Printer; Sending data externally between devices
Parallel data transmission
Multiple bits sent at the same time using multiple wires; E.g. Computer to Modem; Sending data internally
Is serial dt faster than parallel dt?
No, it is slower
3 facts about parallel data transmission
fewer errors, cheaper wiring, less chance of data being out of order
Why Serial is used not Parallel to connect devices to PC
single wire means less chance of corruption & reduces cost; more reliable over distances; bits still synchronized after transmission
Asynchronous data transmission
Data being transmitted in an agreed bit pattern; data bits (1s and 0s) are grouped together and sent with CONTROL BITS
Asynchronous dt - ________ of the data knows when the data starts and when it ends
Receiver
Asynchronous dt- Without these _________, it would be IMPOSSIBLE to separate groups of data as they arrived.
Control bits
Asynchronous dt - Prevents _______ from becoming mixed up
Data
Synchronous data transmission
Continuous stream of data
Synchronous dt - Data is accompanied by ________________ generated by an _____________.
Time signals, internal clock; this ensures that the sender & receiver are synchronised