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synchronous and asynchrounous


i was wondering what is the different between synchronous and asynchronous

communication ?

and what is the meaning of that ?

is ppp for example is synchronous or asynchrounous ?

is f/r for is synchronous or asynchrounous ?

could f/r or ppp be both ? - sometime synchronous and sometime asynchrounous ?

hmm - thanks again

Community Member

Re: synchronous and asynchrounous

In short:

Asynchronous transmission uses start and stop bits/signals for every byte send. If no data is beeing send, the line is not used. Normally used in low-speed applications.

Synchronous transmssion sends continuously signals over the line with predeterminated bitcombination if it isnt data. Always a signal that is used for sync. Even if there arnt data to send, a predetermend bitpattern is send. Normally used i high-speed applications.

To sum up:

Asynchronous recevier runs clock async/unsynched with respect to tthe incoming signal.

Synchronous receciver operats in sync with the recevied signal.

This communication is about the encoding over a line.

PPP is an encapsulationprotocol that can be used on both asynch and synch transmission. PPP is a data link layer protocol of OSI. This is all about how to transfer data over a line.

Community Member

Re: synchronous and asynchrounous

thanks for your answer

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