Difference Between Synchronous Transmission and Asynchronous Transmission

Main Difference

The difference between synchronous transmission and asynchronous transmission is that in synchronous transmission data is send in the form of blocks or frames whereas in asynchronous transmission data is send one byte or one character at a time.

Synchronous Transmission vs. Asynchronous Transmission

The difference between serial transmission and parallel transmission is very similar to synchronous transmission and asynchronous transmission. In serial transmission data is sent bit by bit whereas in parallel transmission a chuck of data is sent at the same time. In synchronous transmission, data is sent in the form of blocks or frames. There is a flow of data in full duplex mode that is in the form of blocks or frames. In synchronous, there is a connection between sender and receiver, that connection between sender and receiver is very important because sender should know where the new byte starts as there is no gap between data during transmission in synchronous transmission. The most important thing about synchronous transmission is that it is very efficient and reliable. In asynchronous transmission data is send one byte or one character at a time. There is a half-duplex mode in asynchronous transmission in which 1 byte or 1 character is sent as flow at a time. There is a continuous stream of bytes flows in asynchronous transmission. In asynchronous transmission, there is a continuous transmission of data. 8 bit of data is first transmitted to which parity bit is added after 8 bit there is a start and stop bit that makes it a total of 10 bits at a time. There is a clock that keeps the connections in synchronous transmission whereas there is no clock in asynchronous transmission. The main difference between synchronous transmission and asynchronous transmission is that in synchronous transmission data is send in the form of blocks or frames whereas in asynchronous transmission data is send one byte or one character at a time. There is a clock in the transmission process; this clock controls the flow to data in transmission. In synchronous transmission, sender and receiver have synchronized clocks that are required for the data transmission whereas if we talk about asynchronous transmission, there is no need of clock because in parallel transmission there is an addition of a parity bit to the data before transmission. Synchronous transmission is used for transferring a large amount of data that is not possible in parallel transmission. There is real time communication in synchronous transmission, as there should be connected devices in synchronous transmission. If we talk about the different examples of synchronous transmission then face to face interactions, video conferencing, telephonic conversations and chat rooms are some examples of synchronous transmission. There is no clock in asynchronous transmission because there is a parity bit to tell the receiver how to interpret data. There is no 2 way connection in the asynchronous transmission that’s why it is simple, fast and very economical. If we talk about the examples of asynchronous transmission, then the examples of asynchronous transmission are letters, emails, forums, televisions and radios.

Comparison Chart

BasisSynchronous TransmissionAsynchronous Transmission
MeaningIn synchronous transmission data is send in the form of blocks or framesIn asynchronous transmission data is send one byte or one character at a time.
Rate of transmissionThe rate of transmission of data is fast in Synchronous TransmissionThe rate of transmission of data is slow in Asynchronous Transmission
CostSynchronous transmission is expensiveAsynchronous transmission is economical
ExamplesExamples of synchronous transmission then face to face interactions, video conferencing, telephonic conversations and chat rooms.The examples of asynchronous transmission are letters, emails, forums, televisions and radios.

What is Synchronous Transmission?

In synchronous transmission, data is sent in the form of blocks or frames. There is a flow of data in full duplex mode that is in the form of blocks or frames. In synchronous, there is a connection between sender and receiver, that connection between sender and receiver is very important because sender should know where the new byte starts as there is no gap between data during transmission in synchronous transmission. The most important thing about synchronous transmission is that it is very efficient and reliable. Synchronous transmission is used for transferring a large amount of data that is not possible in parallel transmission. There is real time communication in synchronous transmission, as there should be connected devices in synchronous transmission. If we talk about the different examples of synchronous transmission then face to face interactions, video conferencing, telephonic conversations and chat rooms are some examples of synchronous transmission.

What is Asynchronous Transmission?

In asynchronous transmission data is send one byte or one character at a time. There is a half-duplex mode in asynchronous transmission in which 1 byte or 1 character is sent as flow at a time. There is a continuous stream of bytes flows in asynchronous transmission. In asynchronous transmission, there is a continuous transmission of data. 8 bit of data is first transmitted to which parity bit is added after 8 bit there is a start and stop bit that makes it a total of 10 bits at a time. There is a clock that keeps the connections in synchronous transmission whereas there is no clock in asynchronous transmission. There is no clock in asynchronous transmission because there is a parity bit to tell the receiver how to interpret data. There is no 2 way connection in the asynchronous transmission that’s why it is simple, fast and very economical. If we talk about the examples of asynchronous transmission, then the examples of asynchronous transmission are letters, emails, forums, televisions and radios.

Key Differences

  1. In synchronous transmission data is send in the form of blocks or frames whereas In asynchronous transmission data is send one byte or one character at a time.
  2. The rate of transmission of data is fast in Synchronous Transmission whereas Rate of transmission of data is slow in Asynchronous Transmission.
  3. Synchronous transmission is expensive whereas Asynchronous transmission is economical.
  4. Examples of synchronous transmission then face to face interactions, video conferencing, telephonic conversations and chat rooms whereas the examples of asynchronous transmission are letters, emails, forums, televisions and radios.

Comparison Video

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Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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